VI.A
BARE OVERHEAD TRANSMISSION
CONDUCTOR RATINGS
DMS #590159
Page 1 of 47
Originally Issued: 10/09
Revised: 03/01/10
GUIDE FOR DETERMINATION OF
BARE OVERHEAD TRANSMISSION CONDUCTORS
PJM INTERCONNECTION
January 2010
Heritage MAAC Group
A task force of the Transmission and Substation Subcommittee
PJM Overhead Conductor Ad Hoc Committee:
Baltimore Gas & Electric
Lamar Kimp (Chairman)
PECO Energy
William Magee
PECO Energy
Stephen Dasovich
PECO Energy
Mark Shuck
PPL Electric Utilities
Christian Sorensen
Public Service Electric & Gas
Dmitriy Katsev
DMS #590159
Page 2 of 47
Originally Issued: 10/09
Revised: 03/01/10
Table of Contents
REVISION HISTORY ................................................................................................................................... 5
SCOPE AND PURPOSE .............................................................................................................................. 6
BACKGROUND ......................................................................................................................................... 7
DEFINITIONS ............................................................................................................................................ 8
NON-THERMAL RATING LIMITATIONS ..................................................................................................... 9
WEATHER ................................................................................................................................................. 9
WEATHER MODEL........................................................................................................................................... 9
DEFINITION OF SUMMER AND WINTER .............................................................................................................. 11
MAXIMUM CONDUCTOR TEMPERATURE ............................................................................................... 11
EFFECTS OF ELEVATED TEMPERATURE OPERATION ............................................................................... 12
LOSS OF STRENGTH DUE TO ANNEALING ............................................................................................................ 12
PREDICTING LOSS OF STRENGTH OF CONDUCTORS DUE TO ANNEALING.................................................................... 13
CREEP EFFECTS OF ELEVATED TEMPERATURE OPERATION ..................................................................................... 14
ALUMINUM WIRE COMPRESSION OF ACSR CONDUCTORS OPERATING AT ELEVATED TEMPERATURES ........................... 14
FITTINGS/ACCESSORIES/HARDWARE ..................................................................................................... 16
RISK ....................................................................................................................................................... 16
FIGURE 8-1 ................................................................................................................................................. 17
EMERGENCY RATINGS .................................................................................................................................... 18
LOAD DUMP RATINGS .................................................................................................................................... 18
PARAMETERS FOR CALCULATIONS ......................................................................................................... 19
NORMAL CONDITIONS ................................................................................................................................... 19
EMERGENCY & LOAD DUMP CONDITIONS .......................................................................................................... 20
DISCUSSION OF ASSUMPTIONS FOR AMPACITY CALCULATIONS USING THE METHOD OF IEEE STD. 738-2006 ............... 21
IEEE STANDARD 738-2006 FOR CALCULATING THE CURRENT-TEMPERATURE OF BARE OVERHEAD
CONDUCTORS ........................................................................................................................................ 22
DESCRIPTION OF IEEE 738 ............................................................................................................................. 22
INSTRUCTIONS FOR USING THE PJM OHT CONDUCTOR RATINGS SPREADSHEET ................................... 23
COMPARISON OF THE PJM OHT CONDUCTOR RATING SPREADSHEET ................................................... 25
APPENDIX 1 FREQUENCY DISTRIBUTION OF WIND AND AMBIENT TEMPERATURE CONDITIONS ........... 27
TABLE 12-1 – SUMMER .............................................................................................................................. 27
TABLE 12-2 – WINTER................................................................................................................................. 28
FIGURE 12-3................................................................................................................................................ 29
DMS #590159
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Originally Issued: 10/09
Revised: 03/01/10
APPENDIX 2 EXAMPLE OF LOSS OF STRENGTH CALCULATIONS .............................................................. 30
EXAMPLE OF LOSS OF STRENGTH CALCULATION FOR 1590 KCMIL 45/7 ACSR (LAPWING) ......................................... 30
STEP 1
CALCULATE INITIAL STRENGTH OF THE CONDUCTOR AND ALUMINUM AND STEEL COMPONENTS ................. 31
STEP 2
DETERMINE REMAINING STRENGTH (RS) OF ALUMINUM STRANDS ....................................................... 31
STEP 3
DETERMINE THE REMAINING STRENGTH OF THE CONDUCTOR .............................................................. 31
STEP 4
DETERMINE LOSS OF STRENGTH OF THE CONDUCTOR ......................................................................... 31
STEADY STATE THERMAL RATINGS......................................................................................................... 32
REFERENCES ........................................................................................................................................... 47
DMS #590159
Page 4 of 47
Originally Issued: 10/09
Revised: 03/01/10
REVISION HISTORY
August 2000:
Rev. 0 – Original Document
March 2010: Rev. 1 – General revision and document standardization and clarification of
emergency and load dump ratings, revision of associated equations, and upgrade of associated
Excel spreadsheet.
DMS #590159
Page 5 of 47
Originally Issued: 10/09
Revised: 03/01/10
SCOPE AND PURPOSE
In 2008 the Heritage MAAC group requested that the PJM Transmission and Substation
Subcommittee provide an update to the Bare Overhead Transmission Conductor Ratings guide.
An Ad Hoc Committee was formed and charged with addressing the following issues:
The PJM Overhead Transmission (OHT) Ratings spreadsheet was expanded to include
conductors rated 100 kV and above, which are considered part of the Bulk Electric System (BES)
and are subject to the guidelines set forth in the PJM Operating Manuals. High Temperature
Low Sag (HTLS) conductors such as aluminum conductor composite core (ACCC) and aluminum
conductor composite reinforced (ACCR) were also added to the spreadsheet. Transmission
owners also have the ability to add additional conductors to the spreadsheet as needed.
The OHT Ratings spreadsheet was updated to include a method for calculating the conductor
load dump ratings. All ratings in the spreadsheet are given in amperes and diligence should be
used when converting to MVA when using nominal voltage (e.g. phase imbalances, operating
voltage).
The output of the OHT Ratings spreadsheet was modified to match that in the Outdoor
Substation Conductor Ratings. Due to the number of conductors now included in the
spreadsheet and the addition of the load dump rating it was decided that this updated
document will not include a printout of all the EXCEL outputs in Appendix 6. Instead only a
sample output will be included. Instructions for using the latest version of the spreadsheet have
also been added.
This document addresses the issues associated with the rating of bare overhead conductors.
Often these ratings are the most limiting ratings on a circuit or feeder, but not always. The
ratings provided in this document must not be confused with circuit ratings; they are only one
component in the analysis to determine the circuit rating. This document and the ratings
spreadsheet are voluntary guidelines and may be applied at the transmission owner’s discretion.
The committee was also charged with defining the transition point between transmission and
substation ratings jurisdictions. Working in conjunction with the Outdoor Substations
Conductor Ratings Ad Hoc Committee the following consensus was established:
“Regardless of the installation method, the point of demarcation is the connection of the
insulator string to the overhead conductor at the dead end structure. The dead end referenced
should be the structure that transitions the line to any type of substation equipment.
Underground cable transition is at the end of the pot head.”
However, the intent of the point of demarcation is to prevent a high temperature overhead
conductor from overheating temperature sensitive substation equipment. Conductor drops
from a take-off tower may be rated as line conductor if attached to non-temperature sensitive
substation components.
DMS #590159
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Originally Issued: 10/09
Revised: 03/01/10
BACKGROUND
This guide outlines a methodology for determining thermal ratings of overhead transmission
conductors. This document resulted from the effort to update an earlier PJM guide: Bare
Overhead Transmission Conductor (November, 2000). The bulk of the work of the Overhead
Conductor Ad-Hoc Committee focused on the following:






Defining the transition between transmission and substation rating jurisdiction.
Inclusion of high temperature conductors (ACSS, ACCR, ACCC).
Describing the impact of high temperature conductor on interface with lower
temperature conductor.
Addressing the thermal effect of multiple conductors in close proximity.
Defining the procedure for determining load dump ratings.
Revising the existing spreadsheet for calculating overhead ratings.
A major accomplishment was the update of the existing Microsoft Excel spreadsheet for
determining overhead ratings. The spreadsheet was revised to include a full range of modern
high-temperature conductors. Additionally, functionality for determining load dump ratings was
developed and included in the spreadsheet. The spreadsheet was thoroughly tested to ensure
comparable performance to industry-standard programs for determining overhead conductor
ratings. A how-to guide on the use of the new spreadsheet is provided in this document. A
comparison table showing the output values of the spreadsheet and commercial software is also
provided.
The assumptions regarding climatic and conductor conditions remain unchanged from the
previous revision of the document. An engineer already familiar with overhead ratings and the
previous revision of this document will not notice any significant changes in the core algorithm
for determining the overhead ratings. The entire document, however, is more-user friendly
compared to the earlier edition as much of the vague or subtle verbiage has been revised or
eliminated. The year 2000 manual is included as an appendix of this document. All versions of
this document dated prior to 2000 are included in the appendices as well.
It is assumed that power levels will be maintained and managed within the requirements of PJM
Manual 3, Section 2, “Thermal Operating Guidelines”. PJM operating philosophy strives to
restore loads to below the Normal Rating in four hours or less. The intent of this guide is that
equipment loading will not be above the Normal Rating for greater than four hours. It is
understood that under a single event restoration, cumulative time of loading, in excess of the
Normal Rating, beyond four hours may occur. Operating in excess of four hours above the
Normal Rating for a single event restoration should be evaluated by the equipment owner.
DMS #590159
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Originally Issued: 10/09
Revised: 03/01/10
DEFINITIONS
Following are definitions of terms used in this report for use in determining PJM switch ratings:
Continuous Duty
A duty that demands operation at a substantially constant load for an indefinitely long time.
Short Time Duty
A duty that demands operation at a substantially constant load for a short and definitely
specified time.
Normal Conditions
All equipment in normal configuration, normal ambient weather conditions.
Normal Rating
The maximum permissible constant load at normal conditions, at the maximum allowable
conductor temperature for that conductor.
Emergency Conditions
Equipment has been operating at Normal Rating. The equipment is then exposed to an out of
configuration condition and emergency ambient weather conditions.
Emergency Rating
The maximum permissible steady-state load at emergency conditions, at the maximum
allowable conductor temperature for a period not to exceed 24 hours.
Load Dump Rating
The maximum permissible load at emergency conditions, at the maximum allowable conductor
temperature for a period of 15 minutes as determined by the transient method.
Weather Conditions
Ambient temperature, solar and sky radiated heat flux, wind speed, wind direction, and
elevation above sea level.
Max. Allowable Conductor Temp.
The maximum temperature limit that is selected in order to minimize loss of strength, conductor
sag, line losses, or a combination of the above.
Time Risk
The time during which the conductor is vulnerable to operation at temperatures greater than
the design temperature.
Temperature Risk
The maximum increase in conductor temperature above design temperature which can be
experienced if the conductor carries its rated current simultaneously with an occurrence of the
most severe set of ambient conditions.
DMS #590159
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Originally Issued: 10/09
Revised: 03/01/10
Non-thermal Rating Limitations
Situations may arise where limitations other than the thermal rating of the conductor will limit
the maximum rating of the circuit. Other electrical devices such as wave traps, switches,
transformers, disconnects, breakers, and relays. Legal or contractual limitations will sometimes
restrict operating practices to limit magnetic fields due to field concerns. On shared rights-ofway, other entities (railroads, for example) may impose maximum current limits to minimize
inductive interference.
Interference issues should always be addressed when determining loading on a line. Potential
interference or inductive coupling may cause hazards to other utilities or other lines within the
right of way.
At times system conditions require a limit on the maximum amount of current flowing through a
line. This may require the line being taken out of service or devices added which limit the
amount of current carried through the line.
Weather
Ambient weather conditions have a major effect on the calculation of a conductor’s thermal
rating. Wind speed is the most widely varying parameter and the most important determinant
of ratings. Careful selection of weather parameters for thermal rating calculations is as
important as the selection of method of calculation itself and requires considerable engineering
judgment.
Since the publication of “Ambient Adjusted Thermal Ratings For Bare Overhead Conductors” in
May 1980 and its acceptance by the PJM companies, wind speed and ambient temperature
became the major determining factor related to weather for the calculation of steady state
thermal ratings of conductors for daily operation.
In the original PJM work, the weather data included 10 years of data from Pittsburgh (1/1/49 –
12/31/58) and 16 years of data from Washington D.C. National Airport (1/1/49 – 12/31/64).
These were added together and used as being the total composite hourly record of wind data
for 26 years. Any differences between the two different weather data sets were obscured by
combining the data.
Weather Model
Under actual operating conditions, conductors experience fluctuations in load and
weather conditions. This complex relationship is not adequately represented by a set of
fixed parameters. A probabilistic model, however, can utilize actual weather data and
load cycle characteristics to represent the conductor’s operating history. This model
produces a time distribution of conductor temperature which can be used to calculate
the loss of strength that a conductor would experience. This modeling technique allows
conductors to be rated to meet the constraints of maximum allowable temperature
and/or allowable loss of strength.
DMS #590159
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A weather model is the heart of the simulation. Weather conditions, especially wind,
have a marked effect on conductor temperatures. For the PJM weather model, detailed
weather data were gathered from several locations representative of the PJM area. Two
of the locations had hourly recordings of weather data on magnetic tape for periods
exceeding ten years. These hourly recordings were summarized in frequency
distribution tables, called “wind roses” which tabulate the statistical distribution of wind
speed for each five-degree range of ambient temperature. Wind roses were prepared
from day and night data in order to allow the exclusion of solar heating during the night
hours.
The hour-by-hour weather data used to make the wind roses was examined to
determine whether prolonged periods of simultaneous still air and high temperature
exist. No such prolonged periods were found; three successive hours at temperatures in
excess of 25°C was the longest period recorded.
However, this examination of the wind roses for each of the locations revealed a higher
than expected occurrence of recorded still air. The same data indicated few occurrences
of one and two knot winds. The Environmental Sciences Services Administration (ESSA)
was consulted for an explanation, and the wind roses were studied by their Science
Advisory Group at the National Weather Records Center (NWRC.) The NWRC advised
that due to bearing friction and inertia in the standard cup anemometers used by ESSA,
many of these instruments will not begin to record until the wind speed exceeded two
or three knots. A paper, “Bias Introduced by Anemometer Starting Speeds in
Climatological Wind Rose Summaries” discussed this problem and concluded that there
is indeed a strong measurement bias but offered no solution to the problem of how to
overcome this bias. The NWRC suggested that the calm hours be apportioned over the
zero, one, and two knot ranges. This reapportionment was made and the resulting
adjusted weather data from several locations in PJM territory were combined into a
single matrix. Computations using weather data from each individual location yielded
results which were essentially identical to those computations made using the
combined data. Based on this computation, it was decided that a single weather model
can be used.
In order to complete the simulation of the operating experience of the conductor, it is
necessary to determine the shape of the load cycle, which the conductors will
experience. A representative load cycle was prepared from studies of actual PJM line
loadings. A step function approximation was made to represent this cycle.
The 2000 Task Force believed that if it had to purchase new weather data, the weather
data would lead to the same conclusions, based on anecdotal information. Glenn
Davidson, who did much of the original work as the Chair of the 1973 PJM Conductor
Rating Task Force, and who attended the May 1999 meeting of this Task Force, also
shared this opinion.
The 2009 Task Force accepted the assumptions made in the original PJM Conductor
Rating calculations to remain valid and applicable.
DMS #590159
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Originally Issued: 10/09
Revised: 03/01/10
Definition of Summer and Winter
For planning purposes summer is defined as the nine month period extending from
March through November and having an ambient temperature of 35°C. Winter is
defined as the three month period extending from December through February and
having an ambient temperature of 10°C. These values are very conservative as the
winter wind chills are less than or equal to 10°C over 88% of the time. The actual
summer temperatures are less than or equal to 35°C 99% of the time. These are the
values used by planners to determine the need to add transmission capacity. The
system operators have tables of ambient adjusted ratings with values between -15° and
40° in 5 degree increments to determine ampacities in effect at any given temperature.
Maximum Conductor Temperature
Each Transmission Owner determines the maximum operating temperature for a conductor by
consideration of several factors. Those factors include:



The requirement to maintain clearance from the aerial line conductors to the ground
and other features.
The capability of the specific conductor type to operate at a given temperature without
an unacceptable reduction in strength or corrosion protection.
The compatibility of the conductor temperature with fittings and other line hardware
and insulation.
The National Electrical Safety Code (NESC) sets the minimum permissible clearance to ground
and other features for aerial transmission lines. In some cases the practice of Transmission
Owners is to design and operate lines with a specified margin of clearance in excess of the NESC
minimums. The selected maximum operating temperature of line conductors shall be
consistent with design and operating assumptions for maximum line sag and the design
clearance to ground and other features and obstructions.
The minimum strength required for a conductor is set by the NESC and by specific requirements
of the individual Transmission Owners. The strength requirement is a factored value of the
design tension of the line. Application of high temperature to stranded conductors can reduce
the strength of the conductor and could impact compliance with NESC and Transmission Owner
requirements.
For conductors such as ACSR, ACAR, and AAC that use hardened aluminum wires (1350-H19) or
aluminum-alloy wires (6201-T81), the application of temperatures in excess of 100°C can result
in annealing of the wires and loss of strength. The selection of the maximum operating
temperature for these conductor types requires an assessment of the expected loss of strength
over the expected life of the line compared to the required strength set by NESC or owner
requirements. Section 6 examines the implications of elevated temperature operation and
discusses risk assessment.
ACSS conductors use annealed aluminum wires (1350-0). The rated strength of ACSS conductors
is primarily the strength of the steel core plus the small strength contribution of the annealed
DMS #590159
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aluminum wires. Since the aluminum wires are already annealed, application of high
temperature will not further reduce the strength of the wires or the overall conductor. In the
case of ACSS conductors, the maximum temperature is limited by the temperature susceptibility
of the protective coating of the steel core wires and temperature capability of dead-ends,
spices, and other fittings. Typically the steel core wires of ACSS conductors use a zinc - 5%
aluminum-mischmetal alloy coating (Galfan) instead of conventional galvanizing to permit
operation up to 250°C.
Conductor types with non-metallic cores (ACCC and ACCR, for example) use a composite
material as the primary strength member of the conductor replacing the typical steel core wires.
These conductor types use aluminum wires as the conductive component of the construction.
The aluminum wires may be hardened, annealed, or may be a heat-resistant aluminum alloy
(aluminum-zirconium). The maximum operating temperature of non-metallic core conductors
should be determined by the properties of the specific conductor materials, both the core and
the aluminum, as set by the conductor manufacturer.
Effects of Elevated Temperature Operation
Operation of bare overhead conductors at elevated temperatures can have detrimental effects
on the strength and sag characteristics of the conductor. Those effects can occur when
operating temperatures exceed 100°C.
Loss of Strength due to Annealing
Annealing is the metallurgical process where applied temperature softens hardened
metal resulting in loss of strength. As applied to bare, overhead conductors, annealing
can degrade the strength of aluminum 1350-H19 wires: the wires used in ACSR and AAC
conductors. About 70% of the strength of 1350-H19 aluminum is a result of hardening.
Annealing of aluminum 1350-H19 begins at 93°C and is a function of both the magnitude
of the temperature and the duration of the application. At lower temperatures (below
100°C), the effect is negligible. At higher temperatures (above 200°C), the effect can be
significant and occur quickly.
The rated strength of a stranded conductor is the sum of the strengths of the individual
wires, factored to account for stranding. An all-aluminum conductor (AAC) derives all its
strength from the aluminum wires. In the case of AAC, the loss of strength of the
conductor due to annealing is directly proportional to the degradation of the aluminum.
Similarly, aluminum conductor, alloy reinforced conductors (ACAR) use both 1350-H19
wires and aluminum-alloy 6201-T81 wires. Both are subject to annealing, and the loss
of strength for ACAR is directly proportional to the degradation of the aluminum and
aluminum-alloy. For both AAC and ACAR conductors, the maximum allowable
conductor temperature should not significantly exceed the annealing temperature of
aluminum. Conductor operating temperatures of up to 100°C have a negligible risk of
annealing the aluminum wires and are considered acceptable for AAC and ACAR
conductors.
DMS #590159
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Aluminum conductor, steel reinforced conductors (ACSR) use a core of steel wires
overlaid by one or more layers of aluminum 1350-H19 wires. The steel wires will not
anneal at temperatures used for ACSR operation. For ACSR, the loss of strength of the
conductor is a function of the loss of strength of the aluminum wire component of the
conductor compared to the rated strength of both the aluminum and steel wires. A
typical ACSR conductor derives about half it its strength from the steel wires and half
from the aluminum wires. ACSR Drake (795kcmil 26/7), for example, derives 44% of its
strength from the aluminum wires and 56% from the steel wires. If elevated
temperature operation reduces the strength of the aluminum wires by 20%, the overall
strength of the conductor will be reduced by 9%. Since the degradation of the
aluminum wires only partially impacts the overall conductor strength, conductor
temperature in excess of the annealing temperature of aluminum can be applied to
ACSR such that the maximum loss of overall strength of the conductor is limited to 10%.
Some aerial conductor types are designed to eliminate or reduce the effect of annealing
on conductor strength. Aluminum conductor, steel supported conductors (ACSS) use
fully annealed aluminum 1350-0 wires over a core of steel wires. The strength of ACSS
conductor is virtually all from the steel core. Since the aluminum wires are already
annealed, elevated temperature operation has no effect on the strength of the
aluminum wires or the conductor. Accordingly, the maximum temperature of ACSS
conductors is set by the thermal capability of connectors and by the heat resistance of
the protective coating on the steel wires.
New conductor constructions use composite core materials. These conductors also use
aluminum wires surrounding the composite core that are either annealed or are heat
resistant during high-temperature operation. The specific effects of temperature on
these types of conductors should be obtained from the manufacturer.
Predicting Loss of Strength of Conductors due to Annealing
Calculating the projected loss of strength of ACSR and other conductors subject to
annealing at elevated temperatures requires a complex analysis of the metallurgical
aspects of the wires and the probability of weather and electrical power flow conditions.
The operating temperature of the conductor is a function of several inter-related
parameters that include wind and the current being carried. The line rating and the
associated conductor operating temperature are based on electric current and weather
parameters that are conservative to ensure safe and reliable system operation.
However, actual wind speeds will generally be higher than that assumed for ratings, and
actual electrical load will generally be less than the full line rating. Thus the conductor
operating temperature of most lines will almost always be lower than the maximum
temperature used for rating the line. Most lines will experience design-case conditions
and operating temperatures for a few hours a year, at most.
The loss of strength due to annealing of the aluminum wires is a temperature and time
dependant phenomenon. The key to determining the probable loss of strength over the
expected life of the conductor is to predict the amount of time the conductor will
experience temperatures that will result in annealing. That time prediction requires an
assessment of the projected load patterns of the line and the predicted wind patterns.
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Once a matrix of load and wind is established, a tabulation of conductor temperatures
and expected durations can be developed. From that tabulation the cumulative
annealing effect can be calculated and the projected remaining strength of the
conductor can be determined.
Appendix 2 provides guidance to the calculation of predicted loss of strength of
conductors subject to annealing. The information and sample calculation in Appendix 2
is highly simplified and is not appropriate for all conditions.
For specific information regarding the effect of high temperature operation on bare
overhead conductors see:
IEEE-1283-2004; IEEE Guide for Determining the Effects of High-Temperature Operation
on Conductors, Connectors, and Accessories; Institute of Electrical and Electronics
Engineers
Creep Effects of Elevated Temperature Operation
Operation of conductors at high temperature can increase the creep effect of
conductors affecting sag. Creep is the non-elastic relaxation of material over time. The
effect of creep on aerial conductors is to have line sag increase over years even in the
absence of extreme loading events. Aluminum 1350-H19 wires are subject to creep.
Lines designed for elevated temperature operation should have sags and tensions
derived with creep as a consideration in order to ensure adequate clearance to ground
and other obstructions over the long term.
Aluminum Wire Compression of ACSR Conductors Operating at Elevated
Temperatures
Research has indicated that ACSR conductors exposed to high temperature operation
can sag more than the values predicted by conventional sag-tension programs. This is
the result of the aluminum wires going into compression at high temperatures. The
coefficient of thermal expansion of aluminum wire is higher than that of steel wire.
Subject to elevated temperatures, the aluminum wires of ACSR will attempt to lengthen
more than the steel wires. Since the aluminum wires are held tightly to the steel wires
by the stranding, the aluminum wires will be forced to the same elongation as the steel
wires. The result is that the aluminum wires at high temperature will either buckle
outward in an effect called “bird caging”, or the wires will go into a compressive stress
state. If the aluminum wires go into compression, they will impose an equal tensile
force on the steel wires. That additional tension will clause the steel wires to elongate
more than predicted by conventional methods and will result in greater line sag. The
greater sag could result in unexpected clearance issues.
The actual, real world impact of aluminum wire compression is not clear. Typically it is
not an issue for operating temperatures up to 120°C. Even at higher temperature it may
range from nothing, if the aluminum wires are assumed to birdcage and relieve
compression, to 100% of theoretical aluminum wire compression. For a typical line
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using ACSR Drake conductor with 900-foot spans and operating at 140°C, the additional
sag resulting from the assumption of aluminum wire compression is about 2 feet.
Most modern sag-tension calculation programs permit analysis assuming aluminum wire
compression as an option. The decision to assume compression of the aluminum wires
of ACSR should be governed by operating experience.
Figure 8-1
Conductor Loss of Strength in % Based on PJM Weather Model
From the 1973 PJM Report
Conductor Size
o
100
110
Maximum Design Conductor Operating Temperature (
120
125
130
140
150
2493 kcm 54/37 ACAR
2312 kcm 76/19 ACSR
2.83
1.58
3.76
2.65
5.77
4.25
7.56
5.08
9.72
6.18
8.54
2300 kcm 84/19 ACSR
2167 kcm 72/7 ACSR
0.00
1.40
0.68
2.45
1.95
4.17
2.76
4.98
3.55
5.91
5.57
8.30
7.77
2156
1780
1590
1590
84/19 ACSR
84/19 ACSR
54/19 ACSR
45/7 ACSR
0.00
0.00
0.00
0.00
0.18
0.71
0.00
0.86
1.49
1.95
0.00
2.15
2.26
2.79
0.20
2.95
2.96
3.53
0.80
3.80
4.90
5.63
2.30
5.71
7.11
7.79
4.20
8.03
9.93
6.40
8.40
1272 kcm 54/19 ACSR
1272 kcm 45/7 ACSR
1033.5 kcm 54/7 ACSR
1033.5 kcm 45/7 ACSR
0.00
0.00
0.00
0.00
0.00
0.85
0.00
0.88
0.00
2.25
0.00
2.25
0.18
2.94
0.27
3.08
0.86
3.87
1.00
3.93
2.43
6.09
2.52
5.88
4.19
8.17
4.24
8.28
6.24
8.30
10.47
6.33
8.31
10.34
795 kcm 30/19 ACSR
0.00
0.00
0.00
0.00
0.00
0.00
0.62
1.95
3.46
4.92
795 kcm 26/7 ACSR
634.9 kcm 12/7 ACAR
0.00
3.09
0.00
4.19
0.00
6.23
0.00
7.77
0.00
9.98
1.20
2.80
4.40
6.20
8.00
556.5 kcm 24/7 ACSR
477 kcm 26/7 ACSR
336 kcm 26/7 ACSR
336.4 kcm 18/1 ACSR
0.00
0.00
0.00
1.30
0.00
0.00
0.00
2.56
0.00
0.00
0.00
4.78
0.42
0.00
0.04
5.83
1.06
0.26
0.58
6.98
2.80
1.68
1.92
9.03
4.20
2.94
2.94
5.88
4.34
4.37
7.85
6.07
5.98
9.74
7.92
7.82
300 kcm 26/7 ACSR
300 kcm 19 str AAC
0.00
5.43
0.00
7.61
0.00
10.28
0.08
0.74
2.02
2.94
4.32
6.08
7.87
kcm
kcm
kcm
kcm
Assumptions:
170
180
Conductor operates for 35 years to PJM Load Cycle as shown in Appendix #3, Pg A-7, Figure #3
Conductor emissivity =0.7 and apsorptivity =0.9
Winter Rating Conditions:
Normal 20
Summer Rating Conditions: Normal 35
DMS #590159
C)
160
o
C, no wind / Emerg 10
o
C, no wind / Emerg 20
Page 15 of 47
o
C, 1 knot
o
C, 1 knot
Originally Issued: 10/09
Revised: 03/01/10
Fittings/Accessories/Hardware
Fittings used on a transmission line serve both electrical and mechanical functions. Conductor
fitting must be compatible with the conductor type and the selected maximum operating
conductor temperature.
Electrically, the fittings must establish and maintain low contact resistance, must not generate
radio noise at the design voltage and must not exceed the temperature of the conductor.
Mechanically, full tension fittings must be capable of holding 95% of the conductor’s rated
strength and non-tension fittings should be capable of holding at least 10% of the rated strength
of the conductor.
Compression fittings, properly installed with the manufacturer’s recommended practice and
joint compound, are capable of transferring the maximum current.
Fittings used with conductors operating at high temperature, typically over 200°C, should be
designed specifically for high temperature operation. Lines using conventional fittings should
not be operated at temperatures in excess of the fitting capability regardless of the conductor
type. If the rating of an existing line is to be increased by increasing the maximum operating
temperature, an assessment should be made to ensure the compatibility of the existing fittings
with the proposed operation. There is a PJM study that addresses this concern.
Risk
As discussed previously, overhead conductor ratings are affected by many factors, but the most
significant of these many parameters is wind speed. But unlike many of the other factors such
as absorptivity, ambient temperature, conductor resistance, etc., wind speed is truly variable in
magnitude and direction. In the early PJM work, summarized by the “Determination of Thermal
Ratings for Bare Overhead Conductor, 1973”, weather data was collected from Washington DC
over a period of 16 years, and from Pittsburgh over a 10 year period. These data were pooled to
represent a 26-year span for an average PJM condition. The weather data were summarized on
pages A18 and A19 in the 1973 Report in a table format for the frequency distribution of wind
and ambient temperature conditions. The tables are reprinted in this report as Appendix 1,
Tables 12-1 and 12-2. In these tables each row list the probability of occurrence of a given wind
speed at a specified ambient temperature. Alternately, each row gives the probability of
occurrence of different ambient temperatures given the particular wind speed.
When rating transmission conductors, the choice of wind speed used is important due to the
significant effect on the rating. While a higher wind speed is desired for the higher rating, there
is a cost. What happens if the wind speed that actually occurs along the transmission line is less
than the assumed value? As the original PJM work showed, the wind speed is characterized by a
distribution of wind speeds with higher and lower values. A wind speed lower than assumed
would drive a higher conductor temperature than assumed. For example, if a rating were based
upon 100C with 2 feet/sec. of wind and a lesser wind were to occur it would cause an increase
in conductor temperature above 100°C. This risk of increase in conductor temperature is called
temperature risk.
DMS #590159
Page 16 of 47
Originally Issued: 10/09
Revised: 03/01/10
The duration of these lower wind speeds is also of concern. The acceptability of a temperature
risk changes with the duration of that risk. For example, while a temperature overrun of 25 C
would not be of major concern for 5 minutes, it would be more problematic if it were for 6
hours during mid-day. The risk due to the duration of an over temperature condition is called
time risk.
Figure 8-1 shown below depicts these risks. On the horizontal axis are listed wind speeds, and
on the vertical axis are the probabilities of wind speeds at or less than the listed values. For
example wind speeds of 1 knot (1.69 ft./sec.) or less are likely 1% of the time, and this increases
to 10% for 4 knots (6.76 ft./sec.) of wind.
Figure 8-1
DMS #590159
Page 17 of 47
Originally Issued: 10/09
Revised: 03/01/10
This chart also details the temperature risk as the labels next to each data point. For example,
with 3 knots of wind the temperature of an overhead transmission conductor would increase in
temperature by up to 104oC at different combinations of ambient temperatures and lesser wind
speeds. For this 3-knot condition, the temperature risk would be 104C with the time risk
equivalent to 5% of the time, or 438 hours per year.
The original PJM CRTF evaluated these risks and developed a reasonable approach to manage
these risks. Normal ratings were to be based upon 0 knots of wind. This is a conservative
approach since there is no risk that a lesser wind speed would occur. Therefore there is neither
temperature nor time risk. The original PJM work determined that a conductor would operate
under emergency conditions for 350 hours over its 35 year life. As a result, this approach was
chosen knowing that the normal rating applies 99.9% of the time. However, the original CRTF
did acknowledge the need for an increased rating for an emergency condition. In an effort to
provide this capability, an emergency rating based upon 1 knot of wind was selected. This
condition resulted in a 1% risk of a lesser wind speed occurring (time risk) and this was believed
to be acceptable for an emergency condition. Additionally, the temperature risk was calculated
to be approximately 30C for the commonly used PJM 230 kV Lapwing transmission conductor.
While this is fairly significant, the resulting increase in conductor sag was calculated to be
approximately 2 feet for a standard 230 kV span length and tension. This increase in sag was up
to about 3 feet safety factor that all PJM companies added to the required ground clearance
requirements. Therefore the temperature risk was actually of no effect since NESC clearances
were not violated.
The recommendation of the 1999 CRTF and the 2009 Ad Hoc group regarding wind and weather
assumptions for normal and emergency ratings is given in Section 9.0.
Emergency Ratings
Emergency ratings are provided for abnormal out of configuration system conditions.
These ratings allow the system operators to take advantage of ambient wind speed to
ride through short time duties without endangering the public.
Since a 1% risk is accepted for emergency ratings, these ratings are limited to abnormal
configurations and a very specific duration. The longer the short time duration, the
more risk is assumed.
Emergency Rating periods are not to exceed 24 hours. Due to the thermal time constant
of electrical conductors, all emergency ratings longer than 15 minutes are essentially the
same. The only increase available is by assuming more risk.
Load Dump Ratings
Load dump ratings are calculated on a similar basis as Emergency Ratings except that
the duration of the Load Dump period shall not exceed 15-minutes. The same
conditions as stated in Section 8.1 for Emergency Ratings apply; however, initial
conditions are based upon parameters set forth in section 9.
DMS #590159
Page 18 of 47
Originally Issued: 10/09
Revised: 03/01/10
Parameters for Calculations
This section of the report summarizes the assumed program parameters for normal and
emergency conditions.
Normal Conditions
Normal Operating Conditions assume that all equipment and conductors are available
and in normal operating configuration. The normal weather conditions, as listed below,
are assumed to exist during normal operating conditions. During normal weather
conditions it is assumed that the conductor under consideration can operate at
continuous duty. The normal ratings are based upon normal weather conditions and
have insignificant risk of exceeding the conductor’s design temperature since they
incorporate a zero wind speed.
Typical Normal Conditions-Summer
Ambient Temperature:
35C
Wind Speed:
0 feet per second
Wind Direction:
90o to conductor
Solar/ Sky:
Day -Industrial
Elevation:
200 ft above sea level
Max. Allowable conductor temp.: 100°-250°C(material dependent)
Latitude:
40 North
Sun Time:
14:00
Emissivity:
0.7
Absorptivity:
0.9
Typical Normal Conditions-Winter:
Ambient Temperature:
10C
Wind Speed:
Wind Direction:
Solar/ Sky:
0 feet per second
90o to conductor
Elevation:
Max. Allowable conductor temp.:
Latitude:
Sun Time:
Emissivity:
Absorptivity:
200 ft above sea level
100-250°C(material dependent)
40 North
14:00
0.7
0.9
Day - Industrial
Note: The ambient temperatures above are used for planning and represent two of the
ambient temperature sets used for operations.
DMS #590159
Page 19 of 47
Originally Issued: 10/09
Revised: 03/01/10
Emergency & Load Dump Conditions
Emergency Operating Conditions require that the conductor under consideration
operate for a short time above its normal rating. The weather conditions for conductor
rating during emergency conditions are specified below. Therefore, this short time
emergency rating is limited to no more than 24 hours per occurrence and 15 minutes for
load dump ratings. These ratings are based upon a 1 % risk of exceeding the
conductor’s design temperature.
Typical Emergency Conditions-Summer:
Ambient Temperature:
35C
Wind Speed:
1.5 Kt. (2.533 ft/sec.)
Wind Direction:
90o to conductor
Solar/ Sky Radiated Heat Flux:
Day - Industrial
Elevation:
200 ft above sea level
Max. Allowable conductor temp.:
100-250°C(material dependent)
Latitude:
40 North
Sun Time:
14:00
Emissivity:
0.7
Absorptivity:
0.7
Typical Emergency Conditions-Winter:
Ambient Temperature:
10C
Wind Speed:
1.5 Kt. (2.533 ft/sec. )
Wind Direction:
90o to conductor
Solar/ Sky Radiated Heat Flux:
Day - Industrial
Elevation:
200 ft above sea level
Max. Allowable conductor temp.:
100-250°C(material dependent)
Latitude:
40 North
Sun Time:
14:00
Emissivity:
0.7
Absorptivity:
0.9
Note: The ambient temperatures above are used for planning and represent two of the
ambient temperature sets used for operations.
DMS #590159
Page 20 of 47
Originally Issued: 10/09
Revised: 03/01/10
Discussion of Assumptions for Ampacity Calculations
Using the Method of IEEE Std. 738-2006
Day and Night Ratings
Daylight hours are, for operating purposes, between sunrise and sunset. Night ratings
should be used during all other periods.
Atmosphere
The task force evaluated the environmental conditions in the PJM service area and
selected the “industrial” atmosphere.
Sun Time
The sun times available for use range between 10:00 am and 2:00 pm in hourly steps.
The task force chose 2:00 p.m. because that time is nearest to the typical peak ambient
temperature.
Latitude
The task force chose 40 degrees north as this latitude approximately divides the PJM
service territory in half.
Conductor Direction
The task force studied a geographic map of the PJM service territory and determined
that it became apparent that most lines are primarily oriented east-west. Therefore this
direction was chosen as the input for the program.
Wind Direction
The task force chose the wind angle of 90 degrees to the conductor, which is
consistent with earlier PJM work. It also results in maximum cooling for any
given wind speed.
Conductor Elevation
The task force discussed the various terrain and elevations within their
respective areas and agreed to a conductor elevation of 200 feet above sea level
as a good average value.
Conductor Resistance
Conductor AC resistance values are calculated by each manufacturer and these
values may vary for the same conductor type and size. This can cause a variance
in the rating calculation. ASTM committee B-1 is considering development of a
standardize methodology for calculating AC resistance values. Until ASTM issues
their methodology document it is recommended that each utility consistently
use ac resistance values from one source. The AC resistance values used in the
PJM rating spreadsheet are listed in the spreadsheet. Each utility is responsible
to verify that the ac resistance values in the spreadsheet meet their standard.
DMS #590159
Page 21 of 47
Originally Issued: 10/09
Revised: 03/01/10
Emissivity/Absorptivity
The task force sees no reason to change the values of emissivity and absorptivity
adopted in previous reports as these values are the result of original work. To our
knowledge, this work has never been repeated.
The values used are:
emissivity = 0.7,
absorptivity = 0.9 for daytime and 0.0 for nighttime.
For additional discussion, see Appendix C of the 1973 PJM Report.
Conductor Temperature
Maximum conductor operating temperature should be between 100C and 250C.
IEEE Standard 738-2006 For Calculating the Current-Temperature of Bare
Overhead Conductors
The 2009 PJM Ad-Hoc group was tasked with updating the existing “PJM OHT Conductor Rating”
spreadsheet by adding Load Dump Rating calculations and updating the format to match the
format of the “Outdoor Substation Conductor Ratings” spreadsheet. The new spreadsheet
contains a new user friendly data input page and an updated rating report. For each conductor
the spreadsheet calculates 72 ratings consisting of the normal, emergency and transient rating
in 5° increments from -15°C to 40°C for day and night conditions.
The new “PJM OHT Conductor Rating” spreadsheet is based on the overhead conductor
methodology as set forth in IEEE 738-2006, “Standard for Calculating the Current Temperature
of Bare Overhead Conductors”.. Copies of the standard are widely available at modest cost.
Further, the method is based upon the 1958 work of House and Tuttle as modified by a group
sponsored by the East Central Area Reliability Co-Ordination Agreement (ECAR) and is similar to
the “PJM Method” of calculating bare overhead conductor ratings Due to the iterative process
of calculating load dump the spreadsheet was written using Visual Basic in Microsoft Excel. All
the parameters contained in IEEE 738-2006 may be modified in the spreadsheet. The PJM
parameters listed in section 9 have been set as default.
The database contains most transmission conductors in service today. The spreadsheet’s
database has been designed so additional conductors may be easily added. A copy of the
spreadsheet is available from PJM for all members.
Description of IEEE 738
The standard presents a method of calculating the current-temperature relationship of
bare overhead conductors.
The conductor temperature is a function of:
 Conductor material
 Conductor diameter
 Conductor surface condition
 Ambient weather conditions
 Conductor electrical current
DMS #590159
Page 22 of 47
Originally Issued: 10/09
Revised: 03/01/10
This standard includes mathematical methods for the calculation of conductor
temperatures and conductor thermal ratings. Due to a great diversity of weather
conditions and operating circumstances for which conductor temperatures and/or
thermal ratings must be calculated, the standard does not list actual temperaturecurrent relationships for specific conductors or weather conditions. Each user must
make an assessment of which weather data and conductor characteristics are
appropriate.
The equations relating electrical current to conductor temperature may be used in
either of the following two ways:
 To calculate the conductor temperature when the electrical current is known
 To calculate the current that yields a given maximum allowable conductor
temperature
The calculation methods developed in this standard are also valid for the calculation of
conductor temperature under fault conditions.
Instructions for using the PJM OHT Conductor Ratings Spreadsheet
To run the program, we follow the following steps:
1. Open the spreadsheet and click on “Select Conductor.” A new window for “Calculation
Set Up” opens up.
DMS #590159
Page 23 of 47
Originally Issued: 10/09
Revised: 03/01/10
2. Choose the type of the conductor from the given list under the “Conductor Type”
section.
3. Click on the name of the conductor from the given list under the “Name of Conductor”
section.
4. Review the month, day, time and atmospheric conditions parameters. The spreadsheet
defaults to the PJM values. Adjust parameters as required and click “Select”
5. To calculate the rating of the conductor click “Calculate” on the spread sheet.
6. Click on “Export.” This will save the report to your current desktop.
DMS #590159
Page 24 of 47
Originally Issued: 10/09
Revised: 03/01/10
7. To get the ratings for another conductor, click on “Select Conductor” again, and follow
the same procedure. The report will be saved in a new spreadsheet on the desktop.
8. To add a conductor which is not on the list, click on “Add Conductor” on the
spreadsheet. Input the information and click on “Add Conductor.” To add the entry
manually, click on “Manual Entry.”
The PJM parameters listed in section 9 have been set as default but all the parameters of IEEE
738-2006 may be modified in the spreadsheet. The max allowable conductor temperatures for
the various conductor specifications can be modified by double clicking on the values in the
“Data Input” workbook.
Comparison of the PJM OHT Conductor Rating Spreadsheet
A comparison was made between the results of the PJM Ratings spreadsheet, Rate Kit and PLS
Cadd using 795 ACSR 26/7 “Drake” conductor. The maximum conductor operating temperature
was chosen to be 140 °C and the AC resistance of the conductor was fixed at 0.177Ω/1000 ft
@25 °C and 0.139Ω/1000 ft @75 °C for all runs. All other parameters were set to the PJM
default values listed in section 9. The results between the PJM spreadsheet and the two
programs varied by less than 1%. Figure 12-1 shows the results of the comparison.
DMS #590159
Page 25 of 47
Originally Issued: 10/09
Revised: 03/01/10
A second comparison of the spreadsheet was performed with the PJM OHT Ratings Spreadsheet
and Ratekit using several different conductors and maximum operating temperatures. The
deviation between the two methods was found to be less than 1%. Figure 12-2 shows the
results of the comparison.
DMS #590159
Page 26 of 47
Originally Issued: 10/09
Revised: 03/01/10
Appendix 1 Frequency Distribution of Wind and Ambient Temperature
Conditions
Table 12-1 – SUMMER
COMPOSITE WEATHER DATA
PITTSBURGH AND WASHINGTON D.C.
PITTSBURGH 1/1/49 - 12/31/58
NATIONAL AIRPORT 1/1/49 - 12/31/64
-
10 YEARS
16 YEARS
TOTAL COMPOSITE HOURLY RECORD -
26 YEARS
FREQUENCY OF OCCURRENCE (PERCENT)
SUMMER DAYS
WIND SPEED-KNOTS
AMBIENT TEMP.

C
0
5
10
15
20
25
30
35
Over 35
0
1
2
3
4
5
0.009
0.038
0.059
0.070
0.103
0.109
0.059
0.012
0.000
0.459
0.025
0.115
0.176
0.209
0.311
0.324
0.178
0.034
0.001
1.373
0.042
0.195
0.299
0.355
0.528
0.550
0.302
0.058
0.001
2.330
0.024
0.247
0.345
0.484
0.655
0.791
0.496
0.127
0.003
3.172
0.059
0.326
0.519
0.741
1.049
1.405
0.962
0.261
0.009
5.331
0.070
0.427
0.634
0.955
1.401
1.743
1.381
0.389
0.010
7.010
5
OVER 5
1.830
6.455
8.811
11.147
14.559
17.949
14.708
4.650
0.187
80.296
SUMMER NIGHTS
WIND SPEED-KNOTS
AMBIENT TEMP.

C
0
5
10
15
20
25
30
35
Over 35
0
1
2
3
4
0.031
0.125
0.174
0.257
0.351
0.236
0.037
0.000
0.000
1.211
0.090
0.373
0.524
0.773
1.020
0.711
0.112
0.001
0.000
3.604
0.153
0.632
0.887
1.312
1.730
1.207
0.188
0.002
0.000
6.111
0.114
0.659
0.987
1.174
1.582
1.671
0.342
0.006
0.000
6.535
0.248
0.921
1.340
1.654
2.254
2.205
0.426
0.013
0.000
9.061
0.271
1.135
1.453
2.089
2.600
2.582
0.516
0.011
0.000
10.657
OVER 5
2.998
8.495
10.003
11.975
13.952
12.846
2.490
0.064
0.000
62.823
Note: Data is taken from page A-18, of 1973 PJM report,
"Determination of Thermal Ratings for Bare Overhead Conductors".
DMS #590159
Page 27 of 47
Originally Issued: 10/09
Revised: 03/01/10
Table 12-2 – WINTER
COMPOSITE WEATHER DATA
PITTSBURGH AND WASHINGTON D.C.
PITTSBURGH 1/1/49 - 12/31/58 - 10 YEARS
NATIONAL AIRPORT 1/1/49 - 12/31/64
- 16 YEARS
TOTAL COMPOSITE HOURLY RECORD - 26 YEARS
FREQUENCY OF OCCURRENCE (PERCENT)
WINTER DAYS
WIND SPEED-KNOTS
AMBIENT TEMP.

C
0
5
10
15
20
25
30
35
Over 35
0
1
2
3
4
5
OVER 5
0.105
0.233
0.118
0.046
0.007
0.000
0.000
0.000
0.000
0.509
0.321
0.695
0.354
0.134
0.023
0.000
0.000
0.000
0.000
1.527
0.541
1.184
0.600
0.230
0.039
0.000
0.000
0.000
0.000
2.594
0.751
1.633
0.875
0.282
0.062
0.003
0.000
0.000
0.000
3.606
1.315
2.380
1.079
0.344
0.062
0.000
0.000
0.000
0.000
5.180
1.649
2.912
1.351
0.433
0.082
0.003
0.000
0.000
0.000
6.430
22.146
31.418
16.749
7.302
2.164
0.348
0.007
0.000
0.000
80.134
WINTER NIGHTS
WIND SPEED-KNOTS
AMBIENT TEMP.

C
0
5
10
15
20
25
30
35
Over 35
0
1
2
3
4
5
OVER 5
0.287
0.450
0.136
0.023
0.004
0.000
0.000
0.000
0.000
0.900
0.856
1.345
0.411
0.078
0.008
0.000
0.000
0.000
0.000
2.698
1.453
2.282
0.791
0.132
0.016
0.000
0.000
0.000
0.000
4.674
1.581
2.778
0.709
0.151
0.004
0.000
0.000
0.000
0.000
5.223
2.709
3.286
0.884
0.213
0.012
0.000
0.000
0.000
0.000
7.104
3.038
3.592
1.073
0.190
0.012
0.000
0.000
0.000
0.000
7.905
27.265
28.548
10.873
3.953
0.918
0.008
0.000
0.000
0.000
71.565
Note: Data is taken from page A-19, of 1973 PJM report,
"Determination of Thermal Ratings for Bare Overhead Conductors".
DMS #590159
Page 28 of 47
Originally Issued: 10/09
Revised: 03/01/10
Figure 12-3
PJM LOAD CYCLE
(SUMMER AND WINTER)
WEEKDAY
100
%
70
of
normal
rating
DAYLIGHT HOURS
12 M
8 AM
12 N
AM
8 PM
12 M
8 PM
12 M
PM
TIME OF DAY
WEEK END
100
%
70
of
normal
rating
DAYLIGHT HOURS
12 M
8 AM
12 N
AM
PM
TIME OF DAY
DMS #590159
Page 29 of 47
Originally Issued: 10/09
Revised: 03/01/10
Appendix 2 Example of Loss of Strength Calculations
Example of Loss of Strength Calculation for 1590 kcmil 45/7 ACSR (Lapwing)
The following Temperatures and Durations were obtained from the weather model
computer program developed for the 1973 PJM conductor report
Temperature (°C)
100
105
110
115
120
125
130
135
Duration (Hours)
402
284
225
132
67
14
1
1
From the Paper “Effect of Elevated Temperature Operation on the Strength of
Aluminum Conductors” (reference 13.1) the following equations and variables for
calculating loss of strength in ACSR conductors are:
 STR EC 
 STR ST 
  100  
  1.09
RS  RS EC  
 STR T 
 STR T 
RS EC   0.24  T  134   t
If  0.24  T  134  100
 0.001T  0.095 
0.1
d
Use 100
Where:
RS
=
Remaining strength as a percentage of initial strength.
RS EC
=
Remaining strength as a percentage of initial strength of the EC strands.
T
=
Temperature (°C)
t
=
Elapsed time (hours)
D
=
Strand diameter (inches)
STR EC =
Calculated initial strength of EC strands (lb)
STR ST =
Calculated initial strength of the steel core (lb)
STR T
Calculated initial strength of the conductor (lb)
DMS #590159
=
Page 30 of 47
Originally Issued: 10/09
Revised: 03/01/10
Step 1 Calculate Initial Strength of the Conductor and Aluminum and Steel
Components
From: ASTM B232 “Standard Specification for Concentric-Lay Stranded Aluminum
Conductors, Coated-Steel Reinforced (ACSR)”
Aluminum
45 strands @ 0.1880" dia. ea., Area of One Strand = 0.02776 in2 , Rating Factor = 91%
Average Tensile Strength (ASTM B230) = 24.0 ksi
Steel
7 strands @ 0.1253" dia. Ea. Area of One Strand = 0.01233 in2 Rating Factor = 96%
Strength at 1% Elongation (ASTM B498) = 180.0 ksi
Total Conductor
Aluminum: (STR EC)
Steel Core: (STR ST)
Conductor: (STR T)
 1000 lb 
  0.91  27,285 lb
45  0.02776 in 2  24.0 ksi  
 kip 
 1000 lb 
  0.96  14,915 lb
7  0.01233 in 2 180 ksi  
 kip 
27,285 lb  14,915 lb  42,200 lb
Step 2 Determine Remaining Strength (RS) of Aluminum Strands
Using the equation for RS EC and inputting various temperatures and durations into an
Excel spreadsheet, curves (% Remaining Strength vs. Hours) for each temperature can
be developed. Then using these curves, the remaining strength of the aluminum strands
can be determined.
402 hrs at 100°C results in
284 + 20 hrs at 105°C results in
225 + 47 hrs at 110°C results in
132 + 73 hrs at 115°C results in
67 + 74 hrs at 120°C results in
14 + 61 hrs at 125°C results in
1 + 39 hrs at 130°C results in
1 + 26 hrs at 135°C results in
RS = 98%
RS = 97%
RS = 96%
RS = 94%
RS = 94%
RS = 93%
RS = 93%
RS = 93%
is equivalent to 20 hrs at 105°C
is equivalent to 47 hrs at 110°C
is equivalent to73 hrs at 115°C
is equivalent to 74 hrs at 120°C
is equivalent to 61 hrs at 125°C
is equivalent to 39 hrs at 130°C
is equivalent to 26 hrs at 135°C
Step 3 Determine The Remaining Strength of the Conductor
 STR EC 
 STR ST 
  100  
  1.09
RS  RS EC  
 STR T 
 STR T 
 27,285 lb 
 14,915 lb 
  100  
  1.09  98.65%
RS  93  
 42,200 lb 
 42,200 lb 
Step 4 Determine Loss of Strength of the Conductor
Loss of Strength  100  RS
Loss of Strength  100  98.65  1.35%
DMS #590159
Page 31 of 47
Originally Issued: 10/09
Revised: 03/01/10
Steady State Thermal Ratings
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
336 26/7 ACSR - Linnet
Planning Rating Summer
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
657
867
639
848
621
829
603
809
584
789
565
768
545
746
525
723
504
700
482
675
459
649
435
622
Normal
Emerg
0
2.533
110
110
687
898
671
880
654
862
637
844
620
825
602
805
584
785
565
764
545
743
525
720
504
697
483
672
Normal
Emerg
0
2.533
120
120
717
927
701
910
685
893
669
876
653
858
636
840
619
821
601
802
583
782
565
761
546
740
526
718
Normal
Emerg
0
2.533
125
125
731
940
716
924
700
908
685
891
669
874
652
857
636
838
619
820
602
801
584
781
565
760
546
739
Normal
Emerg
0
2.533
130
130
744
954
730
938
715
923
700
906
684
890
668
873
652
855
636
837
619
818
602
799
584
780
566
759
Normal
Emerg
0
2.533
140
140
771
980
757
965
743
950
728
935
714
919
699
903
684
887
668
870
653
853
636
835
620
816
603
797
Normal
Emerg
0
2.533
150
150
796
1005
783
991
770
977
756
962
742
948
728
932
714
917
699
901
684
885
669
868
654
851
638
833
Normal
Emerg
0
2.533
160
160
821
1029
809
1016
796
1002
783
989
770
975
756
960
743
946
729
931
715
915
700
900
686
883
671
867
Normal
Emerg
0
2.533
170
170
845
1052
833
1040
821
1027
809
1014
796
1001
783
987
770
973
757
959
744
944
730
930
716
914
702
899
Normal
Emerg
0
2.533
180
180
869
1075
857
1063
845
1051
833
1038
822
1026
809
1013
797
1000
785
986
772
972
759
958
746
944
732
929
Rating Condition
-15
-10
-5
0
5
10
15
20
25
30
35
40
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
336 26/7 ACSR - Linnet
Planning Rating Summer
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
695
896
679
878
662
860
645
841
627
821
609
801
591
780
572
758
553
736
533
712
512
688
491
663
Normal
Emerg
0
2.533
110
110
723
925
707
908
692
891
675
873
659
855
642
836
625
816
607
796
589
776
571
754
552
732
532
709
Normal
Emerg
0
2.533
120
120
750
953
735
937
720
920
705
903
689
886
673
869
657
850
641
832
624
813
606
793
589
772
570
751
Normal
Emerg
0
2.533
125
125
763
966
748
950
734
934
719
918
704
901
688
884
673
867
657
849
640
830
623
811
606
791
589
771
Normal
Emerg
0
2.533
130
130
775
978
761
963
747
948
733
932
718
916
703
899
688
882
672
865
656
847
640
828
623
809
606
790
Normal
Emerg
0
2.533
140
140
800
1003
787
989
773
974
759
959
745
944
731
929
717
912
702
896
687
879
672
862
656
844
640
826
Normal
Emerg
0
2.533
150
150
824
1027
811
1014
798
1000
785
985
772
971
758
956
745
941
731
926
716
910
702
894
687
877
672
860
Normal
Emerg
0
2.533
160
160
847
1050
835
1037
823
1024
810
1011
798
997
785
983
772
969
758
954
745
939
731
924
717
908
703
892
Normal
Emerg
0
2.533
170
170
870
1072
858
1060
846
1048
834
1035
822
1022
810
1008
798
995
785
981
772
967
759
952
746
937
732
922
Normal
Emerg
0
2.533
180
180
892
1094
881
1082
870
1070
858
1058
846
1046
835
1033
823
1020
811
1007
798
993
786
980
773
966
760
951
Rating Condition
DMS #590159
-15
-10
-5
0
5
Page 32 of 47
10
15
20
25
30
35
40
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
556 24/7 ACSR - Parakeet
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
927
1191
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
903
1165
878
1139
852
1112
826
1084
799
1055
771
1025
742
993
712
961
681
927
648
891
614
854
971
1234
948
1210
925
1186
901
1160
876
1134
851
1107
825
1080
798
1051
771
1021
743
990
713
958
683
924
120
120
1013
1275
991
1252
969
1229
946
1206
923
1181
900
1156
876
1131
851
1104
826
1077
800
1048
773
1019
745
988
0
2.533
125
125
1033
1294
1012
1273
990
1250
968
1227
946
1204
923
1180
900
1155
876
1129
852
1103
826
1075
800
1047
774
1018
Normal
Emerg
0
2.533
130
130
1053
1313
1032
1292
1011
1271
990
1248
968
1226
946
1202
923
1178
900
1153
877
1128
852
1102
827
1074
802
1046
Normal
Emerg
0
2.533
140
140
1091
1350
1071
1330
1051
1310
1031
1289
1011
1268
990
1246
969
1223
947
1200
925
1176
902
1152
879
1126
855
1100
Normal
Emerg
0
2.533
150
150
1128
1386
1109
1367
1090
1348
1071
1328
1052
1308
1032
1287
1012
1266
991
1244
970
1222
949
1199
927
1175
905
1151
Normal
Emerg
0
2.533
160
160
1163
1420
1145
1402
1127
1384
1109
1365
1091
1346
1072
1326
1053
1306
1034
1286
1014
1265
994
1243
973
1221
952
1198
Normal
Emerg
0
2.533
170
170
1198
1453
1181
1436
1164
1419
1146
1401
1129
1383
1111
1364
1093
1345
1074
1326
1056
1306
1036
1286
1017
1265
997
1243
Normal
Emerg
0
2.533
180
180
1231
1486
1215
1469
1199
1453
1182
1436
1165
1418
1148
1401
1131
1383
1114
1364
1096
1345
1078
1326
1059
1306
1040
1286
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
556 24/7 ACSR - Parakeet
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
984
1235
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
961
1211
937
1185
913
1159
888
1132
863
1105
838
1076
811
1046
784
1016
756
983
727
950
697
915
1024
1276
1002
1253
980
1229
957
1205
934
1179
910
1154
886
1127
861
1100
836
1071
810
1042
783
1011
755
979
120
120
1062
1314
1041
1292
1020
1270
999
1247
977
1224
955
1199
932
1175
909
1149
885
1123
861
1095
836
1067
810
1038
0
2.533
125
125
1080
1333
1060
1311
1040
1290
1019
1267
998
1245
976
1221
954
1197
932
1173
909
1147
885
1121
861
1094
836
1066
Normal
Emerg
0
2.533
130
130
1099
1351
1079
1330
1059
1309
1039
1287
1018
1265
997
1243
976
1219
954
1195
931
1171
909
1146
885
1119
861
1092
Normal
Emerg
0
2.533
140
140
1134
1386
1115
1366
1096
1346
1077
1326
1057
1305
1037
1284
1017
1262
996
1239
975
1216
954
1193
932
1168
909
1143
Normal
Emerg
0
2.533
150
150
1168
1419
1150
1401
1132
1382
1114
1363
1095
1343
1076
1323
1057
1302
1037
1281
1017
1259
997
1237
976
1214
955
1191
Normal
Emerg
0
2.533
160
160
1202
1452
1185
1434
1167
1416
1150
1398
1132
1379
1114
1360
1095
1341
1077
1321
1058
1300
1039
1279
1019
1258
999
1236
Normal
Emerg
0
2.533
170
170
1234
1484
1218
1467
1201
1450
1184
1432
1167
1415
1150
1396
1133
1378
1115
1359
1097
1340
1079
1320
1060
1299
1041
1279
Normal
Emerg
0
2.533
180
180
1266
1515
1250
1499
1234
1482
1218
1466
1202
1449
1186
1431
1169
1414
1152
1396
1135
1377
1117
1359
1099
1339
1081
1320
DMS #590159
-15
-10
Planning Rating Summer
Page 33 of 47
30
35
40
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
795 26/7 ACSR - Drake
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1200
1508
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1168
1476
1136
1442
1103
1408
1069
1372
1034
1336
998
1298
961
1258
922
1217
882
1174
840
1128
796
1081
1258
1564
1228
1534
1198
1503
1167
1471
1135
1438
1102
1404
1069
1369
1035
1332
999
1295
963
1255
925
1214
885
1172
120
120
1312
1617
1284
1589
1256
1560
1227
1530
1197
1499
1167
1467
1136
1435
1104
1401
1071
1366
1037
1330
1002
1293
966
1254
0
2.533
125
125
1339
1643
1312
1615
1284
1587
1256
1558
1227
1528
1197
1498
1167
1466
1137
1434
1105
1400
1072
1366
1039
1330
1004
1292
Normal
Emerg
0
2.533
130
130
1365
1668
1338
1641
1311
1613
1284
1585
1256
1557
1227
1527
1198
1497
1168
1465
1138
1433
1106
1400
1074
1365
1041
1329
Normal
Emerg
0
2.533
140
140
1415
1716
1390
1691
1364
1665
1338
1638
1312
1611
1285
1583
1258
1555
1230
1526
1201
1495
1172
1464
1141
1432
1110
1399
Normal
Emerg
0
2.533
150
150
1463
1762
1439
1738
1415
1714
1391
1689
1366
1663
1340
1637
1314
1610
1288
1583
1261
1555
1233
1526
1205
1496
1176
1465
Normal
Emerg
0
2.533
160
160
1510
1807
1487
1785
1464
1761
1441
1738
1417
1713
1393
1689
1368
1663
1343
1637
1318
1611
1292
1584
1265
1555
1238
1527
Normal
Emerg
0
2.533
170
170
1556
1851
1534
1829
1512
1807
1490
1785
1467
1762
1444
1738
1421
1714
1397
1690
1373
1665
1348
1639
1323
1612
1297
1585
Normal
Emerg
0
2.533
180
180
1600
1893
1580
1873
1558
1852
1537
1830
1516
1808
1494
1786
1471
1763
1449
1740
1426
1716
1403
1692
1379
1667
1354
1642
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
795 26/7 ACSR - Drake
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1275
1569
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1246
1538
1215
1506
1185
1473
1153
1439
1121
1404
1087
1368
1053
1330
1018
1291
982
1251
945
1208
906
1164
1328
1621
1300
1592
1271
1562
1242
1531
1212
1500
1182
1467
1151
1434
1119
1399
1086
1363
1053
1326
1018
1287
982
1247
120
120
1378
1671
1351
1643
1324
1615
1297
1586
1269
1557
1240
1526
1211
1495
1181
1463
1150
1429
1119
1395
1087
1359
1054
1322
0
2.533
125
125
1402
1695
1376
1668
1350
1641
1323
1613
1296
1584
1268
1555
1240
1524
1211
1493
1181
1461
1151
1428
1119
1394
1087
1358
Normal
Emerg
0
2.533
130
130
1426
1718
1401
1692
1375
1666
1349
1639
1323
1611
1295
1582
1268
1553
1240
1523
1211
1492
1181
1460
1151
1427
1120
1392
Normal
Emerg
0
2.533
140
140
1473
1764
1449
1739
1424
1714
1399
1689
1374
1662
1348
1635
1322
1608
1296
1579
1269
1550
1241
1520
1212
1490
1183
1458
Normal
Emerg
0
2.533
150
150
1518
1808
1495
1785
1472
1761
1448
1737
1424
1712
1400
1686
1375
1660
1349
1634
1324
1606
1298
1578
1271
1549
1243
1519
Normal
Emerg
0
2.533
160
160
1562
1851
1540
1828
1518
1806
1495
1783
1472
1759
1449
1735
1425
1710
1401
1685
1377
1659
1352
1633
1327
1606
1301
1578
Normal
Emerg
0
2.533
170
170
1605
1892
1584
1871
1562
1849
1541
1828
1519
1805
1497
1782
1474
1759
1451
1735
1428
1711
1404
1685
1380
1660
1356
1633
Normal
Emerg
0
2.533
180
180
1647
1933
1627
1913
1606
1892
1586
1871
1565
1850
1543
1828
1522
1806
1500
1783
1478
1760
1455
1736
1432
1712
1409
1687
DMS #590159
-15
-10
Planning Rating Summer
Page 34 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
795 30/19 ACSR - Mallard
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1218
1526
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1186
1493
1153
1459
1119
1425
1085
1389
1049
1352
1013
1313
975
1273
936
1231
895
1187
852
1142
808
1094
1276
1583
1246
1552
1216
1521
1184
1488
1152
1455
1119
1421
1085
1385
1050
1348
1014
1310
977
1270
939
1229
898
1186
120
120
1332
1636
1304
1608
1275
1578
1245
1548
1215
1517
1184
1485
1153
1452
1120
1418
1087
1383
1053
1346
1017
1308
981
1269
0
2.533
125
125
1359
1662
1331
1634
1303
1606
1275
1576
1245
1546
1216
1515
1185
1484
1154
1451
1122
1417
1089
1382
1055
1346
1019
1308
Normal
Emerg
0
2.533
130
130
1385
1687
1358
1660
1331
1633
1303
1604
1275
1575
1246
1545
1216
1514
1186
1483
1155
1450
1123
1416
1090
1381
1057
1345
Normal
Emerg
0
2.533
140
140
1436
1736
1411
1711
1385
1685
1358
1658
1332
1631
1304
1602
1277
1574
1248
1544
1219
1513
1189
1482
1159
1450
1127
1416
Normal
Emerg
0
2.533
150
150
1485
1783
1461
1759
1436
1734
1411
1709
1386
1683
1360
1657
1334
1630
1307
1602
1280
1573
1252
1544
1223
1514
1194
1482
Normal
Emerg
0
2.533
160
160
1533
1829
1510
1806
1486
1782
1463
1758
1438
1734
1414
1709
1389
1683
1364
1657
1338
1630
1311
1603
1284
1574
1257
1545
Normal
Emerg
0
2.533
170
170
1579
1873
1557
1851
1535
1829
1512
1806
1489
1783
1466
1759
1442
1735
1418
1710
1394
1685
1369
1659
1343
1632
1317
1605
Normal
Emerg
0
2.533
180
180
1624
1916
1603
1895
1582
1874
1560
1852
1538
1830
1516
1808
1494
1785
1471
1761
1447
1737
1424
1713
1400
1687
1375
1662
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
795 30/19 ACSR - Mallard
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1295
1588
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1265
1557
1234
1524
1203
1491
1171
1457
1138
1421
1104
1385
1070
1347
1034
1307
997
1266
959
1224
920
1179
1348
1641
1320
1611
1291
1581
1261
1550
1231
1518
1200
1485
1169
1451
1136
1416
1103
1380
1069
1342
1034
1303
998
1262
120
120
1399
1691
1372
1663
1345
1635
1317
1606
1288
1576
1259
1545
1230
1514
1199
1481
1168
1447
1136
1412
1104
1376
1070
1339
0
2.533
125
125
1424
1715
1397
1688
1371
1661
1343
1633
1316
1604
1288
1574
1259
1543
1229
1512
1199
1479
1168
1446
1137
1411
1104
1375
Normal
Emerg
0
2.533
130
130
1448
1739
1422
1713
1396
1686
1370
1659
1343
1631
1315
1602
1287
1572
1259
1542
1230
1510
1200
1478
1169
1444
1138
1410
Normal
Emerg
0
2.533
140
140
1495
1785
1471
1761
1446
1735
1421
1709
1395
1683
1369
1656
1343
1628
1316
1599
1288
1570
1260
1539
1231
1508
1202
1476
Normal
Emerg
0
2.533
150
150
1541
1830
1518
1806
1494
1782
1470
1758
1446
1733
1421
1707
1396
1681
1370
1654
1344
1626
1317
1598
1290
1568
1262
1538
Normal
Emerg
0
2.533
160
160
1585
1873
1563
1851
1541
1828
1518
1805
1494
1781
1471
1756
1447
1732
1423
1706
1398
1680
1373
1653
1347
1626
1321
1597
Normal
Emerg
0
2.533
170
170
1629
1915
1608
1894
1586
1872
1564
1850
1542
1827
1519
1804
1497
1781
1473
1756
1450
1732
1426
1706
1401
1680
1377
1654
Normal
Emerg
0
2.533
180
180
1672
1956
1651
1936
1630
1915
1609
1894
1588
1872
1567
1850
1545
1828
1523
1805
1500
1782
1478
1758
1454
1733
1431
1708
DMS #590159
-15
-10
Planning Rating Summer
Page 35 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
795 30/19 ACSR - Mallard
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1218
1526
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1186
1493
1153
1459
1119
1425
1085
1389
1049
1352
1013
1313
975
1273
936
1231
895
1187
852
1142
808
1094
1276
1583
1246
1552
1216
1521
1184
1488
1152
1455
1119
1421
1085
1385
1050
1348
1014
1310
977
1270
939
1229
898
1186
120
120
1332
1636
1304
1608
1275
1578
1245
1548
1215
1517
1184
1485
1153
1452
1120
1418
1087
1383
1053
1346
1017
1308
981
1269
0
2.533
125
125
1359
1662
1331
1634
1303
1606
1275
1576
1245
1546
1216
1515
1185
1484
1154
1451
1122
1417
1089
1382
1055
1346
1019
1308
Normal
Emerg
0
2.533
130
130
1385
1687
1358
1660
1331
1633
1303
1604
1275
1575
1246
1545
1216
1514
1186
1483
1155
1450
1123
1416
1090
1381
1057
1345
Normal
Emerg
0
2.533
140
140
1436
1736
1411
1711
1385
1685
1358
1658
1332
1631
1304
1602
1277
1574
1248
1544
1219
1513
1189
1482
1159
1450
1127
1416
Normal
Emerg
0
2.533
150
150
1485
1783
1461
1759
1436
1734
1411
1709
1386
1683
1360
1657
1334
1630
1307
1602
1280
1573
1252
1544
1223
1514
1194
1482
Normal
Emerg
0
2.533
160
160
1533
1829
1510
1806
1486
1782
1463
1758
1438
1734
1414
1709
1389
1683
1364
1657
1338
1630
1311
1603
1284
1574
1257
1545
Normal
Emerg
0
2.533
170
170
1579
1873
1557
1851
1535
1829
1512
1806
1489
1783
1466
1759
1442
1735
1418
1710
1394
1685
1369
1659
1343
1632
1317
1605
Normal
Emerg
0
2.533
180
180
1624
1916
1603
1895
1582
1874
1560
1852
1538
1830
1516
1808
1494
1785
1471
1761
1447
1737
1424
1713
1400
1687
1375
1662
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
795 30/19 ACSR - Mallard
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1295
1588
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1265
1557
1234
1524
1203
1491
1171
1457
1138
1421
1104
1385
1070
1347
1034
1307
997
1266
959
1224
920
1179
1348
1641
1320
1611
1291
1581
1261
1550
1231
1518
1200
1485
1169
1451
1136
1416
1103
1380
1069
1342
1034
1303
998
1262
120
120
1399
1691
1372
1663
1345
1635
1317
1606
1288
1576
1259
1545
1230
1514
1199
1481
1168
1447
1136
1412
1104
1376
1070
1339
0
2.533
125
125
1424
1715
1397
1688
1371
1661
1343
1633
1316
1604
1288
1574
1259
1543
1229
1512
1199
1479
1168
1446
1137
1411
1104
1375
Normal
Emerg
0
2.533
130
130
1448
1739
1422
1713
1396
1686
1370
1659
1343
1631
1315
1602
1287
1572
1259
1542
1230
1510
1200
1478
1169
1444
1138
1410
Normal
Emerg
0
2.533
140
140
1495
1785
1471
1761
1446
1735
1421
1709
1395
1683
1369
1656
1343
1628
1316
1599
1288
1570
1260
1539
1231
1508
1202
1476
Normal
Emerg
0
2.533
150
150
1541
1830
1518
1806
1494
1782
1470
1758
1446
1733
1421
1707
1396
1681
1370
1654
1344
1626
1317
1598
1290
1568
1262
1538
Normal
Emerg
0
2.533
160
160
1585
1873
1563
1851
1541
1828
1518
1805
1494
1781
1471
1756
1447
1732
1423
1706
1398
1680
1373
1653
1347
1626
1321
1597
Normal
Emerg
0
2.533
170
170
1629
1915
1608
1894
1586
1872
1564
1850
1542
1827
1519
1804
1497
1781
1473
1756
1450
1732
1426
1706
1401
1680
1377
1654
Normal
Emerg
0
2.533
180
180
1672
1956
1651
1936
1630
1915
1609
1894
1588
1872
1567
1850
1545
1828
1523
1805
1500
1782
1478
1758
1454
1733
1431
1708
DMS #590159
-15
-10
Planning Rating Summer
Page 36 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1033.5 45/7 ACSR - Ortolan
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1397
1738
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1360
1701
1322
1662
1284
1623
1244
1582
1204
1540
1162
1496
1118
1450
1073
1402
1027
1353
978
1300
926
1245
1464
1803
1429
1768
1394
1732
1358
1695
1321
1658
1284
1618
1245
1578
1205
1536
1164
1492
1121
1447
1077
1400
1031
1351
120
120
1528
1864
1495
1831
1462
1798
1428
1764
1394
1728
1359
1692
1322
1654
1285
1616
1247
1575
1208
1534
1167
1491
1125
1446
0
2.533
125
125
1558
1894
1527
1862
1495
1829
1462
1796
1428
1762
1394
1727
1359
1691
1324
1653
1287
1615
1249
1575
1210
1533
1170
1490
Normal
Emerg
0
2.533
130
130
1588
1922
1558
1892
1527
1860
1495
1828
1462
1795
1429
1761
1395
1726
1361
1690
1325
1653
1289
1614
1251
1574
1212
1533
Normal
Emerg
0
2.533
140
140
1647
1978
1618
1949
1588
1920
1558
1889
1527
1858
1496
1826
1464
1793
1432
1760
1399
1725
1364
1689
1329
1652
1293
1614
Normal
Emerg
0
2.533
150
150
1703
2032
1675
2005
1647
1977
1619
1948
1590
1919
1560
1888
1530
1858
1500
1826
1468
1793
1436
1760
1403
1725
1370
1690
Normal
Emerg
0
2.533
160
160
1758
2084
1731
2058
1705
2031
1677
2004
1650
1976
1622
1948
1593
1919
1564
1889
1535
1859
1505
1827
1474
1795
1442
1762
Normal
Emerg
0
2.533
170
170
1811
2135
1786
2110
1760
2084
1734
2059
1708
2032
1681
2005
1654
1978
1627
1950
1599
1921
1570
1891
1541
1861
1511
1830
Normal
Emerg
0
2.533
180
180
1862
2184
1838
2160
1814
2136
1789
2111
1764
2086
1739
2061
1713
2035
1687
2008
1660
1981
1633
1953
1606
1924
1578
1895
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1033.5 45/7 ACSR - Ortolan
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1486
1811
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1452
1775
1417
1738
1381
1700
1344
1661
1306
1621
1268
1579
1228
1536
1187
1491
1145
1445
1102
1396
1056
1345
1547
1871
1514
1837
1481
1803
1447
1768
1413
1731
1378
1694
1342
1655
1305
1615
1267
1574
1228
1531
1187
1487
1146
1440
120
120
1605
1928
1574
1897
1543
1864
1511
1831
1478
1797
1445
1762
1411
1726
1377
1689
1341
1651
1305
1611
1267
1570
1229
1528
0
2.533
125
125
1633
1956
1603
1925
1573
1894
1542
1862
1510
1829
1478
1795
1445
1760
1411
1724
1377
1687
1341
1649
1305
1610
1268
1569
Normal
Emerg
0
2.533
130
130
1661
1983
1632
1953
1602
1923
1572
1892
1541
1860
1510
1827
1478
1793
1445
1758
1411
1723
1377
1686
1342
1648
1306
1608
Normal
Emerg
0
2.533
140
140
1715
2036
1687
2007
1659
1979
1630
1949
1601
1919
1571
1888
1541
1856
1510
1824
1478
1790
1446
1756
1413
1720
1379
1684
Normal
Emerg
0
2.533
150
150
1768
2086
1741
2060
1714
2032
1687
2004
1659
1976
1630
1947
1602
1917
1572
1886
1543
1855
1512
1822
1481
1789
1449
1755
Normal
Emerg
0
2.533
160
160
1819
2136
1793
2110
1767
2084
1741
2058
1715
2031
1688
2003
1660
1975
1633
1946
1604
1916
1575
1886
1546
1855
1516
1822
Normal
Emerg
0
2.533
170
170
1868
2184
1844
2160
1819
2135
1794
2110
1769
2084
1743
2058
1717
2031
1691
2004
1664
1975
1636
1947
1608
1917
1580
1887
Normal
Emerg
0
2.533
180
180
1917
2231
1894
2208
1870
2184
1846
2160
1822
2136
1798
2111
1773
2085
1747
2059
1722
2032
1696
2005
1669
1977
1642
1949
DMS #590159
-15
-10
Planning Rating Summer
Page 37 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1033.5 54/7 ACSR - Curlew
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1400
1737
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1363
1700
1326
1662
1287
1622
1248
1581
1207
1539
1165
1495
1121
1449
1076
1402
1029
1352
980
1300
929
1245
1465
1799
1431
1765
1396
1729
1360
1692
1323
1655
1285
1615
1246
1575
1206
1533
1165
1490
1122
1445
1078
1397
1032
1348
120
120
1527
1858
1495
1826
1462
1792
1428
1758
1394
1723
1358
1687
1322
1649
1285
1611
1247
1571
1208
1529
1167
1486
1125
1441
0
2.533
125
125
1557
1887
1526
1855
1493
1823
1461
1790
1427
1756
1393
1721
1358
1685
1323
1647
1286
1609
1248
1569
1209
1528
1169
1485
Normal
Emerg
0
2.533
130
130
1586
1914
1556
1884
1524
1852
1493
1820
1460
1787
1427
1753
1393
1719
1359
1683
1323
1646
1287
1607
1250
1568
1211
1527
Normal
Emerg
0
2.533
140
140
1643
1968
1614
1939
1584
1909
1554
1879
1524
1848
1493
1817
1461
1784
1428
1750
1395
1716
1361
1680
1326
1644
1290
1606
Normal
Emerg
0
2.533
150
150
1697
2019
1669
1992
1641
1964
1613
1936
1584
1906
1555
1877
1525
1846
1494
1815
1463
1782
1431
1749
1399
1715
1365
1680
Normal
Emerg
0
2.533
160
160
1750
2069
1723
2043
1697
2017
1670
1990
1642
1962
1615
1934
1586
1905
1557
1875
1528
1845
1498
1814
1467
1782
1436
1749
Normal
Emerg
0
2.533
170
170
1801
2117
1776
2092
1750
2067
1725
2042
1699
2016
1672
1989
1645
1962
1618
1934
1590
1905
1562
1876
1533
1846
1503
1815
Normal
Emerg
0
2.533
180
180
1850
2164
1826
2140
1802
2117
1778
2092
1753
2068
1728
2042
1702
2016
1676
1990
1650
1963
1623
1935
1596
1907
1568
1878
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1033.5 54/7 ACSR - Curlew
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1490
1810
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1456
1775
1421
1738
1385
1700
1348
1661
1310
1621
1272
1580
1232
1536
1191
1492
1149
1445
1105
1396
1060
1345
1549
1868
1516
1835
1483
1800
1450
1765
1415
1729
1380
1692
1344
1653
1307
1613
1269
1572
1230
1529
1189
1485
1148
1439
120
120
1605
1923
1574
1891
1543
1859
1511
1826
1479
1792
1445
1758
1412
1722
1377
1685
1341
1647
1305
1607
1267
1566
1229
1524
0
2.533
125
125
1632
1949
1602
1919
1572
1888
1541
1856
1509
1823
1477
1789
1444
1754
1411
1719
1376
1682
1341
1644
1305
1605
1268
1564
Normal
Emerg
0
2.533
130
130
1659
1975
1630
1946
1600
1915
1570
1884
1539
1852
1508
1820
1476
1786
1443
1752
1410
1716
1376
1679
1341
1642
1305
1602
Normal
Emerg
0
2.533
140
140
1711
2025
1683
1997
1655
1969
1626
1939
1597
1909
1568
1879
1537
1847
1507
1815
1475
1782
1443
1747
1410
1712
1377
1676
Normal
Emerg
0
2.533
150
150
1762
2074
1735
2047
1708
2020
1681
1992
1653
1964
1625
1935
1596
1905
1567
1875
1537
1844
1507
1812
1476
1779
1445
1745
Normal
Emerg
0
2.533
160
160
1810
2121
1785
2095
1760
2070
1734
2043
1707
2017
1680
1989
1653
1961
1625
1932
1597
1903
1569
1873
1539
1842
1509
1810
Normal
Emerg
0
2.533
170
170
1858
2166
1834
2142
1810
2118
1785
2093
1760
2067
1734
2041
1708
2015
1682
1988
1655
1960
1628
1931
1600
1902
1572
1872
Normal
Emerg
0
2.533
180
180
1905
2211
1882
2188
1858
2165
1835
2141
1811
2117
1786
2092
1762
2067
1736
2041
1711
2015
1685
1988
1659
1960
1632
1932
DMS #590159
-15
-10
Planning Rating Summer
Page 38 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1272 45/7 ACSR - Bittern
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1612
1983
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1570
1940
1526
1897
1482
1851
1436
1805
1389
1757
1341
1706
1291
1654
1239
1600
1185
1543
1129
1483
1069
1420
1690
2058
1651
2019
1610
1978
1569
1936
1526
1893
1483
1848
1438
1802
1392
1754
1344
1704
1295
1653
1244
1599
1191
1542
120
120
1765
2130
1728
2093
1690
2055
1651
2015
1611
1975
1570
1934
1529
1891
1486
1847
1442
1801
1396
1753
1350
1704
1301
1653
0
2.533
125
125
1801
2164
1765
2128
1728
2091
1690
2054
1651
2015
1612
1974
1572
1933
1530
1890
1488
1846
1444
1801
1399
1753
1353
1704
Normal
Emerg
0
2.533
130
130
1836
2198
1801
2163
1765
2127
1728
2091
1691
2053
1653
2014
1614
1974
1574
1933
1533
1890
1491
1847
1447
1801
1403
1754
Normal
Emerg
0
2.533
140
140
1905
2264
1871
2231
1837
2197
1803
2162
1767
2127
1731
2090
1695
2053
1657
2014
1619
1975
1579
1934
1539
1892
1497
1848
Normal
Emerg
0
2.533
150
150
1971
2327
1939
2296
1907
2264
1874
2231
1841
2197
1806
2163
1772
2128
1736
2092
1700
2055
1663
2016
1625
1977
1587
1936
Normal
Emerg
0
2.533
160
160
2035
2388
2005
2358
1974
2328
1943
2297
1911
2265
1879
2233
1846
2200
1812
2166
1778
2131
1743
2095
1708
2058
1671
2020
Normal
Emerg
0
2.533
170
170
2098
2447
2069
2419
2039
2390
2009
2361
1979
2331
1948
2300
1917
2269
1886
2237
1853
2204
1820
2170
1787
2135
1752
2099
Normal
Emerg
0
2.533
180
180
2158
2505
2131
2478
2103
2451
2074
2423
2045
2394
2016
2365
1986
2335
1956
2305
1926
2274
1894
2242
1862
2209
1830
2175
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1272 45/7 ACSR - Bittern
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1717
2069
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1677
2028
1637
1987
1596
1944
1553
1899
1510
1853
1466
1806
1420
1757
1373
1706
1325
1652
1274
1597
1222
1539
1788
2139
1751
2101
1712
2062
1674
2022
1634
1981
1593
1938
1552
1894
1509
1848
1465
1801
1420
1752
1374
1702
1326
1649
120
120
1856
2206
1821
2170
1785
2134
1748
2096
1710
2057
1672
2017
1633
1976
1593
1934
1552
1890
1510
1845
1467
1798
1422
1750
0
2.533
125
125
1889
2238
1855
2204
1820
2168
1784
2131
1747
2094
1710
2055
1672
2016
1633
1975
1594
1933
1553
1889
1511
1844
1468
1797
Normal
Emerg
0
2.533
130
130
1922
2270
1888
2236
1854
2202
1819
2166
1784
2130
1747
2092
1710
2054
1673
2014
1634
1974
1595
1932
1554
1888
1513
1843
Normal
Emerg
0
2.533
140
140
1985
2332
1953
2300
1921
2267
1887
2233
1854
2199
1819
2164
1785
2128
1749
2091
1713
2053
1675
2013
1637
1973
1599
1931
Normal
Emerg
0
2.533
150
150
2047
2391
2016
2361
1985
2330
1954
2298
1922
2266
1889
2232
1856
2198
1822
2163
1788
2128
1753
2091
1717
2053
1680
2014
Normal
Emerg
0
2.533
160
160
2107
2449
2078
2420
2048
2391
2018
2361
1987
2330
1956
2298
1925
2266
1893
2233
1860
2199
1827
2165
1793
2129
1758
2092
Normal
Emerg
0
2.533
170
170
2166
2506
2138
2478
2109
2450
2080
2421
2051
2392
2022
2362
1991
2332
1961
2300
1930
2268
1898
2236
1866
2202
1833
2167
Normal
Emerg
0
2.533
180
180
2223
2561
2196
2535
2169
2508
2141
2481
2113
2453
2085
2424
2056
2395
2027
2366
1998
2335
1968
2304
1937
2272
1906
2240
DMS #590159
-15
-10
Planning Rating Summer
Page 39 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
1272 54/19 ACSR - Pheasant
Condr
Wind
Max
Speed
Temp
Rating Condition (ft/sec) Deg C
Planning Rating Winter
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
Normal
Emerg
0
2.533
100
100
1613
1978
1571
1936
1527
1892
1483
1847
1437
1801
1391
1753
1342
1703
1292
1650
1240
1596
1186
1539
1130
1480
1070
1417
Normal
Emerg
0
2.533
110
110
1689
2051
1649
2011
1609
1971
1568
1929
1525
1886
1482
1841
1437
1795
1391
1748
1344
1698
1294
1647
1243
1593
1190
1537
Normal
Emerg
0
2.533
120
120
1761
2119
1724
2082
1686
2044
1647
2005
1608
1965
1567
1924
1525
1881
1483
1837
1439
1792
1394
1745
1347
1695
1298
1644
Normal
Emerg
0
2.533
125
125
1796
2152
1760
2116
1723
2080
1685
2042
1647
2003
1608
1963
1567
1922
1526
1880
1484
1836
1440
1791
1396
1744
1349
1695
Normal
Emerg
0
2.533
130
130
1830
2184
1795
2150
1759
2114
1722
2077
1685
2040
1647
2001
1608
1962
1569
1921
1528
1879
1486
1835
1443
1790
1398
1743
Normal
Emerg
0
2.533
140
140
1896
2247
1863
2214
1829
2180
1794
2146
1759
2111
1723
2075
1687
2038
1649
1999
1611
1960
1572
1920
1532
1878
1491
1835
Normal
Emerg
0
2.533
150
150
1959
2307
1928
2276
1896
2244
1863
2212
1830
2179
1796
2145
1761
2110
1726
2074
1690
2037
1654
1999
1616
1960
1578
1920
Normal
Emerg
0
2.533
160
160
2021
2365
1991
2335
1960
2305
1929
2275
1898
2243
1866
2211
1833
2179
1800
2145
1766
2110
1731
2075
1696
2038
1660
2001
Normal
Emerg
0
2.533
170
170
2081
2421
2052
2393
2023
2365
1993
2336
1963
2306
1933
2276
1902
2245
1871
2213
1838
2180
1806
2147
1772
2113
1738
2077
Normal
Emerg
0
2.533
180
180
2139
2476
2111
2449
2084
2422
2055
2395
2027
2367
1998
2338
1969
2308
1939
2278
1908
2248
1877
2216
1846
2184
1814
2150
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
1272 54/19 ACSR - Pheasant
Condr
Wind
Max
Speed
Temp
Rating Condition (ft/sec) Deg C
Planning Rating Winter
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
Normal
Emerg
0
2.533
100
100
1719
2065
1679
2025
1639
1983
1597
1940
1555
1896
1512
1850
1467
1803
1422
1754
1375
1703
1326
1650
1276
1594
1224
1536
Normal
Emerg
0
2.533
110
110
1787
2132
1750
2094
1712
2055
1673
2015
1633
1974
1593
1932
1551
1888
1509
1843
1465
1796
1420
1747
1374
1696
1326
1644
Normal
Emerg
0
2.533
120
120
1853
2196
1817
2160
1781
2124
1745
2086
1707
2048
1669
2008
1630
1967
1590
1925
1549
1882
1508
1837
1464
1790
1420
1742
Normal
Emerg
0
2.533
125
125
1884
2226
1850
2192
1815
2156
1779
2120
1743
2083
1706
2044
1668
2005
1629
1964
1590
1923
1549
1879
1508
1835
1465
1788
Normal
Emerg
0
2.533
130
130
1916
2257
1882
2223
1848
2189
1813
2153
1778
2117
1742
2080
1705
2042
1668
2003
1629
1962
1590
1920
1550
1877
1508
1833
Normal
Emerg
0
2.533
140
140
1976
2315
1944
2283
1912
2251
1879
2217
1845
2183
1811
2148
1777
2113
1741
2076
1705
2038
1668
1999
1630
1959
1592
1918
Normal
Emerg
0
2.533
150
150
2035
2371
2005
2341
1974
2310
1942
2279
1911
2247
1878
2214
1845
2180
1812
2146
1778
2110
1743
2074
1707
2036
1671
1997
Normal
Emerg
0
2.533
160
160
2092
2426
2063
2397
2034
2368
2004
2339
1974
2308
1943
2277
1912
2245
1880
2212
1847
2179
1814
2145
1781
2109
1746
2073
Normal
Emerg
0
2.533
170
170
2148
2479
2121
2452
2092
2424
2064
2396
2035
2367
2006
2338
1976
2308
1946
2277
1915
2245
1883
2213
1852
2179
1819
2145
Normal
Emerg
0
2.533
180
180
2203
2532
2176
2506
2150
2479
2122
2452
2095
2425
2067
2397
2038
2368
2009
2339
1980
2309
1950
2278
1920
2247
1889
2214
DMS #590159
Page 40 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1590 45/7 ACSR - Lapwing
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1875
2279
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1826
2230
1776
2180
1724
2128
1671
2074
1617
2019
1561
1961
1502
1901
1442
1839
1379
1773
1314
1704
1244
1632
1968
2368
1922
2322
1875
2275
1827
2227
1777
2178
1727
2126
1675
2073
1621
2018
1566
1961
1509
1901
1449
1839
1387
1774
120
120
2056
2452
2013
2409
1968
2366
1923
2321
1877
2274
1830
2227
1781
2177
1732
2127
1681
2074
1628
2019
1573
1962
1517
1903
0
2.533
125
125
2099
2493
2057
2452
2014
2409
1970
2366
1925
2321
1879
2275
1832
2227
1784
2178
1735
2127
1684
2075
1632
2020
1578
1964
Normal
Emerg
0
2.533
130
130
2141
2533
2100
2493
2058
2452
2015
2409
1972
2366
1927
2321
1882
2275
1836
2228
1788
2179
1739
2129
1688
2076
1636
2022
Normal
Emerg
0
2.533
140
140
2222
2610
2183
2572
2143
2534
2103
2494
2062
2453
2020
2411
1978
2368
1934
2324
1889
2278
1843
2231
1796
2183
1748
2133
Normal
Emerg
0
2.533
150
150
2300
2685
2263
2649
2226
2613
2187
2575
2149
2537
2109
2497
2069
2457
2028
2415
1986
2372
1943
2328
1899
2283
1853
2236
Normal
Emerg
0
2.533
160
160
2376
2758
2341
2723
2305
2689
2269
2653
2232
2617
2195
2580
2156
2541
2118
2502
2078
2462
2037
2421
1996
2378
1953
2335
Normal
Emerg
0
2.533
170
170
2451
2828
2417
2796
2383
2763
2348
2729
2313
2694
2277
2659
2241
2623
2204
2586
2167
2548
2128
2509
2089
2469
2049
2428
Normal
Emerg
0
2.533
180
180
2523
2897
2491
2866
2458
2835
2425
2802
2392
2770
2358
2736
2323
2702
2288
2667
2252
2631
2216
2594
2179
2557
2141
2518
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1590 45/7 ACSR - Lapwing
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2000
2382
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1954
2336
1907
2288
1859
2239
1810
2188
1760
2135
1708
2081
1655
2024
1601
1966
1544
1904
1486
1841
1425
1774
2084
2465
2040
2421
1996
2376
1951
2330
1905
2283
1858
2234
1810
2183
1760
2131
1709
2077
1657
2021
1603
1963
1547
1902
120
120
2164
2544
2123
2503
2081
2460
2039
2417
1995
2373
1951
2327
1905
2280
1859
2231
1811
2181
1763
2129
1712
2076
1661
2020
0
2.533
125
125
2204
2582
2163
2542
2123
2501
2081
2459
2039
2416
1996
2372
1952
2326
1907
2279
1860
2231
1813
2181
1765
2129
1715
2075
Normal
Emerg
0
2.533
130
130
2242
2619
2203
2580
2163
2541
2123
2500
2082
2458
2040
2415
1997
2371
1953
2326
1908
2279
1862
2231
1815
2181
1767
2129
Normal
Emerg
0
2.533
140
140
2317
2692
2280
2655
2242
2618
2204
2579
2165
2540
2125
2500
2084
2458
2043
2415
2001
2372
1958
2326
1913
2280
1868
2232
Normal
Emerg
0
2.533
150
150
2390
2763
2355
2728
2319
2692
2282
2656
2245
2619
2207
2580
2169
2541
2129
2501
2089
2460
2049
2417
2007
2374
1964
2329
Normal
Emerg
0
2.533
160
160
2462
2831
2428
2798
2393
2764
2358
2730
2323
2694
2287
2658
2250
2621
2213
2583
2175
2544
2136
2505
2097
2464
2056
2421
Normal
Emerg
0
2.533
170
170
2531
2898
2499
2867
2466
2835
2432
2802
2398
2768
2364
2734
2329
2699
2294
2663
2257
2626
2221
2588
2183
2550
2145
2510
Normal
Emerg
0
2.533
180
180
2600
2964
2568
2934
2537
2903
2505
2872
2472
2840
2440
2807
2406
2774
2372
2740
2338
2705
2303
2669
2267
2632
2231
2595
DMS #590159
-15
-10
Planning Rating Summer
Page 41 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1590 54/19 ACSR - Falcon
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
1880
2278
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1831
2229
1780
2179
1729
2127
1676
2074
1621
2018
1565
1960
1506
1900
1446
1838
1383
1772
1317
1704
1248
1631
1970
2363
1924
2318
1877
2271
1829
2223
1779
2174
1729
2122
1677
2069
1623
2014
1568
1957
1510
1898
1451
1836
1389
1771
120
120
2055
2444
2012
2402
1968
2358
1923
2313
1877
2267
1829
2220
1781
2171
1731
2120
1680
2067
1627
2013
1573
1956
1517
1897
0
2.533
125
125
2097
2483
2054
2442
2012
2400
1968
2357
1923
2312
1877
2266
1831
2219
1783
2170
1733
2119
1683
2067
1630
2013
1576
1956
Normal
Emerg
0
2.533
130
130
2137
2521
2096
2482
2054
2441
2012
2399
1968
2355
1924
2311
1879
2265
1833
2218
1785
2170
1736
2119
1686
2067
1634
2013
Normal
Emerg
0
2.533
140
140
2215
2595
2176
2558
2137
2519
2097
2480
2056
2439
2014
2398
1972
2355
1928
2311
1884
2266
1838
2219
1791
2171
1743
2121
Normal
Emerg
0
2.533
150
150
2291
2667
2254
2631
2216
2595
2178
2557
2140
2519
2100
2480
2060
2440
2019
2399
1978
2356
1935
2313
1891
2268
1846
2221
Normal
Emerg
0
2.533
160
160
2364
2736
2329
2702
2293
2667
2257
2632
2220
2596
2183
2559
2145
2521
2106
2483
2067
2443
2027
2402
1986
2360
1943
2316
Normal
Emerg
0
2.533
170
170
2435
2802
2401
2770
2367
2738
2333
2704
2298
2670
2263
2635
2227
2600
2190
2563
2153
2526
2115
2487
2076
2448
2036
2407
Normal
Emerg
0
2.533
180
180
2504
2868
2472
2837
2440
2806
2407
2775
2374
2742
2340
2709
2306
2675
2271
2641
2236
2605
2200
2569
2163
2532
2125
2493
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1590 54/19 ACSR - Falcon
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2005
2382
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
1959
2336
1912
2288
1864
2239
1815
2188
1765
2136
1714
2081
1660
2025
1606
1966
1549
1905
1491
1841
1430
1774
2086
2461
2043
2418
1999
2373
1954
2327
1908
2280
1860
2231
1812
2181
1763
2129
1712
2075
1660
2019
1606
1960
1550
1900
120
120
2164
2536
2123
2495
2081
2454
2038
2410
1995
2366
1951
2321
1905
2274
1859
2225
1812
2176
1763
2124
1713
2070
1661
2015
0
2.533
125
125
2202
2573
2162
2533
2121
2492
2079
2451
2037
2408
1994
2364
1950
2318
1905
2272
1859
2223
1812
2174
1764
2122
1714
2069
Normal
Emerg
0
2.533
130
130
2239
2608
2200
2570
2160
2530
2120
2490
2079
2448
2037
2406
1994
2362
1950
2317
1906
2270
1860
2222
1813
2172
1765
2121
Normal
Emerg
0
2.533
140
140
2311
2677
2274
2641
2236
2604
2198
2566
2159
2526
2119
2486
2079
2445
2037
2403
1995
2359
1952
2314
1908
2268
1863
2220
Normal
Emerg
0
2.533
150
150
2381
2744
2345
2710
2309
2675
2273
2638
2236
2601
2198
2564
2160
2525
2121
2485
2081
2444
2041
2402
1999
2359
1957
2314
Normal
Emerg
0
2.533
160
160
2449
2809
2415
2777
2381
2743
2346
2709
2311
2674
2275
2638
2239
2601
2202
2564
2164
2525
2125
2486
2086
2445
2046
2403
Normal
Emerg
0
2.533
170
170
2515
2873
2483
2842
2450
2810
2417
2777
2383
2744
2349
2710
2315
2675
2279
2640
2244
2603
2207
2566
2170
2528
2132
2488
Normal
Emerg
0
2.533
180
180
2581
2935
2550
2905
2518
2875
2487
2844
2454
2812
2422
2780
2389
2747
2355
2713
2321
2679
2286
2643
2251
2607
2215
2570
DMS #590159
-15
-10
Planning Rating Summer
Page 42 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1780 84/19 ACSR - Chukar
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2034
2455
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
1981
2403
1926
2349
1871
2293
1813
2235
1754
2175
1693
2113
1630
2048
1565
1981
1497
1910
1425
1836
1350
1758
2136
2553
2086
2504
2035
2454
1983
2402
1930
2348
1875
2293
1819
2236
1760
2176
1700
2115
1638
2051
1574
1984
1506
1913
120
120
2234
2646
2187
2600
2139
2553
2090
2505
2040
2455
1988
2403
1936
2350
1882
2295
1826
2239
1769
2180
1710
2118
1649
2054
0
2.533
125
125
2281
2691
2235
2647
2188
2601
2141
2554
2092
2506
2043
2456
1992
2405
1940
2352
1886
2297
1831
2241
1774
2182
1715
2121
Normal
Emerg
0
2.533
130
130
2327
2736
2282
2692
2237
2648
2191
2602
2144
2556
2096
2508
2046
2458
1996
2407
1944
2354
1891
2300
1836
2243
1780
2185
Normal
Emerg
0
2.533
140
140
2417
2821
2374
2780
2331
2739
2288
2696
2243
2652
2198
2607
2152
2560
2104
2512
2056
2463
2006
2413
1955
2360
1902
2306
Normal
Emerg
0
2.533
150
150
2504
2904
2463
2865
2423
2826
2381
2785
2339
2744
2296
2701
2252
2658
2208
2613
2162
2567
2115
2519
2067
2470
2018
2420
Normal
Emerg
0
2.533
160
160
2588
2984
2549
2948
2511
2910
2471
2872
2431
2833
2390
2792
2349
2751
2307
2709
2264
2666
2219
2621
2174
2575
2128
2528
Normal
Emerg
0
2.533
170
170
2670
3063
2633
3028
2596
2992
2559
2956
2521
2918
2482
2880
2442
2841
2402
2801
2361
2761
2320
2719
2277
2675
2234
2631
Normal
Emerg
0
2.533
180
180
2750
3139
2715
3106
2680
3072
2644
3037
2607
3002
2571
2966
2533
2929
2495
2891
2456
2852
2416
2812
2376
2772
2335
2730
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
1780 84/19 ACSR - Chukar
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2171
2570
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
2121
2520
2070
2468
2018
2415
1965
2360
1911
2304
1855
2245
1798
2184
1739
2121
1678
2055
1614
1986
1549
1914
2263
2661
2216
2614
2168
2565
2120
2516
2070
2465
2019
2412
1966
2358
1913
2301
1858
2243
1801
2183
1743
2120
1682
2054
120
120
2353
2747
2308
2703
2262
2658
2216
2611
2169
2564
2121
2514
2072
2464
2022
2411
1970
2357
1917
2301
1862
2243
1806
2183
0
2.533
125
125
2396
2790
2352
2747
2308
2703
2263
2657
2217
2611
2170
2563
2123
2514
2074
2464
2024
2412
1973
2358
1920
2302
1866
2244
Normal
Emerg
0
2.533
130
130
2438
2831
2396
2789
2353
2746
2309
2703
2264
2658
2219
2611
2172
2564
2125
2515
2076
2465
2027
2412
1976
2359
1923
2303
Normal
Emerg
0
2.533
140
140
2522
2912
2481
2872
2440
2832
2398
2790
2356
2748
2313
2704
2269
2660
2224
2614
2178
2566
2131
2518
2083
2467
2034
2416
Normal
Emerg
0
2.533
150
150
2603
2990
2564
2952
2525
2914
2485
2875
2445
2835
2404
2793
2362
2751
2319
2708
2276
2663
2231
2618
2186
2571
2140
2522
Normal
Emerg
0
2.533
160
160
2681
3066
2645
3030
2607
2994
2569
2957
2531
2918
2492
2879
2452
2840
2411
2799
2370
2757
2328
2714
2285
2669
2241
2624
Normal
Emerg
0
2.533
170
170
2759
3140
2723
3106
2688
3072
2651
3036
2614
3000
2577
2963
2539
2925
2501
2886
2461
2847
2421
2806
2381
2764
2339
2721
Normal
Emerg
0
2.533
180
180
2835
3213
2801
3181
2766
3148
2732
3114
2696
3079
2661
3044
2624
3008
2588
2971
2550
2934
2512
2895
2473
2856
2434
2815
DMS #590159
-15
-10
Planning Rating Summer
Page 43 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
2167 72/7 ACSR - Kiwi
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2279
2727
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
2219
2669
2158
2609
2096
2547
2032
2483
1966
2416
1897
2347
1827
2275
1753
2200
1677
2122
1597
2039
1513
1952
2395
2839
2340
2785
2283
2729
2224
2671
2164
2612
2103
2550
2040
2487
1975
2421
1908
2352
1838
2281
1765
2206
1690
2128
120
120
2507
2946
2454
2895
2400
2842
2346
2789
2290
2733
2232
2676
2173
2617
2113
2556
2051
2493
1986
2427
1920
2359
1851
2288
0
2.533
125
125
2561
2997
2510
2948
2457
2897
2404
2845
2350
2791
2294
2736
2237
2679
2179
2620
2119
2559
2057
2496
1993
2431
1927
2363
Normal
Emerg
0
2.533
130
130
2614
3048
2564
3000
2513
2951
2461
2900
2409
2848
2355
2795
2299
2740
2243
2683
2185
2624
2125
2563
2064
2500
2000
2435
Normal
Emerg
0
2.533
140
140
2717
3146
2669
3101
2621
3055
2572
3007
2522
2958
2472
2908
2420
2856
2366
2803
2312
2748
2256
2692
2199
2633
2140
2573
Normal
Emerg
0
2.533
150
150
2816
3242
2771
3199
2726
3155
2679
3110
2632
3064
2584
3016
2535
2968
2484
2918
2433
2866
2381
2814
2327
2759
2272
2703
Normal
Emerg
0
2.533
160
160
2913
3334
2870
3293
2827
3252
2783
3209
2738
3165
2692
3121
2645
3075
2598
3028
2550
2979
2500
2930
2450
2879
2398
2826
Normal
Emerg
0
2.533
170
170
3008
3424
2967
3385
2925
3346
2883
3305
2840
3264
2797
3222
2753
3178
2707
3134
2662
3088
2615
3041
2567
2993
2518
2944
Normal
Emerg
0
2.533
180
180
3100
3513
3061
3476
3021
3438
2981
3399
2940
3360
2899
3320
2857
3278
2814
3236
2770
3193
2726
3149
2680
3104
2634
3057
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
2167 72/7 ACSR - Kiwi
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2434
2858
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
2378
2803
2322
2746
2264
2687
2205
2626
2144
2563
2081
2498
2017
2431
1951
2361
1883
2288
1812
2211
1738
2131
2540
2962
2487
2910
2434
2857
2379
2802
2323
2745
2266
2687
2208
2626
2148
2564
2086
2499
2023
2432
1957
2362
1889
2289
120
120
2642
3062
2592
3013
2541
2962
2490
2911
2437
2858
2383
2803
2328
2747
2272
2689
2214
2628
2154
2566
2093
2502
2031
2435
0
2.533
125
125
2692
3110
2643
3062
2593
3014
2543
2963
2492
2912
2439
2859
2386
2804
2331
2748
2275
2690
2218
2630
2159
2568
2098
2504
Normal
Emerg
0
2.533
130
130
2741
3157
2693
3111
2645
3064
2596
3015
2546
2965
2495
2914
2443
2861
2390
2807
2335
2750
2279
2693
2222
2633
2164
2571
Normal
Emerg
0
2.533
140
140
2836
3250
2791
3206
2745
3161
2698
3115
2651
3068
2602
3020
2553
2970
2503
2919
2451
2866
2399
2812
2345
2756
2290
2699
Normal
Emerg
0
2.533
150
150
2929
3340
2886
3298
2842
3256
2797
3212
2752
3168
2706
3122
2659
3075
2612
3027
2563
2977
2513
2926
2462
2874
2410
2820
Normal
Emerg
0
2.533
160
160
3020
3428
2979
3388
2937
3348
2894
3306
2851
3264
2807
3221
2763
3176
2717
3131
2671
3084
2624
3036
2576
2987
2526
2936
Normal
Emerg
0
2.533
170
170
3109
3514
3069
3476
3029
3437
2989
3398
2947
3358
2905
3316
2863
3274
2820
3231
2776
3187
2731
3142
2685
3095
2638
3047
Normal
Emerg
0
2.533
180
180
3197
3598
3159
3562
3120
3525
3081
3487
3042
3449
3001
3410
2961
3370
2919
3329
2877
3287
2835
3244
2791
3200
2747
3154
DMS #590159
-15
-10
Planning Rating Summer
Page 44 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
2300 84/19 ACSR
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2405
2864
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
2343
2803
2279
2740
2213
2675
2145
2608
2075
2538
2003
2466
1929
2390
1851
2311
1771
2228
1686
2142
1598
2050
2528
2982
2470
2925
2409
2866
2348
2806
2285
2743
2220
2679
2153
2612
2085
2543
2014
2470
1940
2395
1864
2317
1784
2235
120
120
2646
3094
2590
3040
2533
2985
2476
2929
2417
2870
2356
2810
2294
2749
2230
2684
2165
2618
2097
2549
2027
2477
1954
2403
0
2.533
125
125
2702
3148
2648
3096
2593
3043
2537
2988
2480
2932
2421
2874
2361
2814
2300
2752
2236
2688
2171
2622
2104
2553
2034
2482
Normal
Emerg
0
2.533
130
130
2758
3201
2705
3150
2652
3099
2597
3046
2542
2991
2485
2935
2427
2877
2367
2818
2306
2756
2243
2692
2178
2626
2112
2558
Normal
Emerg
0
2.533
140
140
2866
3304
2816
3256
2766
3208
2714
3158
2662
3106
2608
3054
2553
3000
2497
2944
2440
2886
2381
2827
2321
2766
2259
2702
Normal
Emerg
0
2.533
150
150
2971
3404
2924
3359
2875
3313
2826
3265
2777
3217
2726
3167
2674
3117
2622
3064
2568
3010
2512
2955
2456
2898
2398
2839
Normal
Emerg
0
2.533
160
160
3073
3501
3028
3458
2982
3414
2935
3369
2888
3324
2840
3277
2791
3229
2741
3180
2690
3129
2638
3077
2585
3023
2530
2968
Normal
Emerg
0
2.533
170
170
3172
3595
3129
3554
3085
3513
3041
3471
2996
3427
2950
3383
2903
3337
2856
3291
2808
3243
2759
3194
2708
3144
2657
3092
Normal
Emerg
0
2.533
180
180
3269
3687
3228
3649
3186
3609
3144
3569
3101
3528
3057
3486
3013
3443
2968
3398
2922
3353
2875
3307
2827
3259
2779
3210
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
2300 84/19 ACSR
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2571
3005
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
2512
2946
2453
2887
2392
2825
2329
2761
2265
2695
2199
2627
2132
2556
2062
2483
1990
2406
1915
2326
1837
2242
2682
3113
2627
3059
2570
3003
2513
2945
2454
2886
2394
2824
2332
2761
2269
2696
2204
2628
2137
2557
2068
2484
1996
2407
120
120
2789
3217
2737
3166
2683
3113
2629
3059
2573
3004
2517
2946
2459
2887
2399
2826
2338
2763
2276
2698
2211
2630
2145
2560
0
2.533
125
125
2842
3268
2790
3218
2738
3167
2685
3114
2631
3060
2576
3005
2519
2948
2462
2889
2403
2828
2342
2765
2280
2700
2216
2633
Normal
Emerg
0
2.533
130
130
2893
3318
2843
3269
2792
3219
2740
3168
2688
3116
2634
3062
2579
3007
2523
2950
2466
2891
2407
2830
2347
2768
2285
2703
Normal
Emerg
0
2.533
140
140
2993
3415
2946
3369
2897
3322
2848
3273
2798
3224
2747
3173
2695
3121
2642
3068
2588
3013
2533
2956
2476
2897
2418
2837
Normal
Emerg
0
2.533
150
150
3091
3509
3045
3465
2999
3420
2952
3375
2905
3328
2856
3280
2807
3231
2757
3181
2705
3129
2653
3076
2600
3021
2545
2964
Normal
Emerg
0
2.533
160
160
3186
3601
3143
3559
3099
3517
3054
3473
3008
3429
2962
3384
2915
3337
2867
3289
2819
3240
2769
3190
2718
3139
2667
3085
Normal
Emerg
0
2.533
170
170
3280
3690
3238
3651
3196
3610
3153
3569
3109
3527
3065
3484
3021
3440
2975
3395
2929
3348
2882
3301
2833
3252
2784
3202
Normal
Emerg
0
2.533
180
180
3371
3778
3331
3741
3291
3702
3250
3663
3208
3623
3166
3582
3123
3540
3080
3497
3036
3453
2991
3408
2945
3362
2898
3315
DMS #590159
-15
-10
Planning Rating Summer
Page 45 of 47
Originally Issued: 10/09
Revised: 03/01/10
DAY - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
2493 54/37 ACAR
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2406
2865
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-15
-10
Planning Rating Summer
-5
0
5
10
15
20
25
30
35
40
2344
2804
2279
2741
2213
2676
2146
2609
2076
2539
2004
2466
1929
2391
1852
2312
1771
2229
1687
2142
1598
2051
2533
2987
2474
2930
2413
2871
2352
2810
2289
2748
2224
2683
2157
2616
2088
2547
2017
2474
1944
2399
1867
2321
1787
2238
120
120
2653
3102
2597
3049
2541
2994
2483
2937
2424
2879
2363
2819
2301
2756
2237
2692
2171
2626
2103
2556
2033
2485
1960
2410
0
2.533
125
125
2712
3159
2658
3107
2602
3053
2546
2998
2489
2942
2430
2884
2370
2824
2308
2762
2244
2697
2179
2631
2111
2562
2041
2490
Normal
Emerg
0
2.533
130
130
2769
3214
2716
3163
2663
3111
2608
3058
2552
3003
2495
2947
2437
2889
2377
2829
2315
2767
2252
2703
2187
2637
2120
2568
Normal
Emerg
0
2.533
140
140
2881
3321
2831
3273
2780
3224
2728
3174
2675
3123
2621
3070
2566
3015
2510
2959
2453
2901
2394
2842
2333
2780
2270
2716
Normal
Emerg
0
2.533
150
150
2990
3425
2942
3380
2893
3333
2844
3286
2794
3237
2743
3187
2691
3136
2638
3083
2584
3029
2528
2973
2471
2916
2413
2857
Normal
Emerg
0
2.533
160
160
3095
3526
3050
3483
3003
3439
2957
3394
2909
3348
2860
3301
2811
3252
2761
3203
2710
3152
2657
3099
2603
3045
2548
2990
Normal
Emerg
0
2.533
170
170
3198
3625
3155
3584
3111
3542
3066
3499
3021
3456
2974
3411
2927
3365
2880
3318
2831
3270
2781
3220
2731
3170
2679
3117
Normal
Emerg
0
2.533
180
180
3299
3721
3258
3682
3215
3643
3173
3602
3129
3560
3085
3518
3041
3474
2995
3430
2949
3384
2902
3337
2854
3289
2804
3240
NIGHT - Steady State Thermal Rating (Ampacity), Amperes
Planning Rating Winter
2493 54/37 ACAR
Wind
Speed
(ft/sec)
Condr
Max
Temp
Deg C
Normal
Emerg
0
2.533
100
100
2572
3006
Normal
Emerg
0
2.533
110
110
Normal
Emerg
0
2.533
Normal
Emerg
Rating Condition
-5
0
5
10
15
20
25
30
35
40
2513
2947
2453
2888
2392
2826
2330
2762
2266
2696
2200
2628
2132
2557
2062
2484
1990
2407
1916
2327
1838
2242
2687
3118
2631
3064
2575
3008
2517
2950
2458
2890
2398
2829
2336
2766
2273
2700
2208
2632
2141
2561
2071
2488
2000
2411
120
120
2797
3227
2745
3175
2691
3122
2636
3068
2581
3012
2524
2955
2466
2895
2406
2834
2345
2771
2282
2706
2218
2638
2151
2568
0
2.533
125
125
2851
3279
2800
3229
2748
3178
2694
3125
2640
3071
2585
3015
2528
2958
2470
2899
2411
2838
2350
2775
2288
2709
2224
2642
Normal
Emerg
0
2.533
130
130
2905
3331
2854
3282
2803
3232
2751
3181
2699
3129
2645
3075
2590
3019
2533
2962
2476
2903
2417
2842
2356
2779
2294
2714
Normal
Emerg
0
2.533
140
140
3009
3432
2961
3386
2912
3339
2863
3290
2812
3241
2761
3190
2709
3137
2656
3084
2601
3028
2546
2971
2489
2912
2430
2851
Normal
Emerg
0
2.533
150
150
3110
3531
3064
3487
3018
3442
2971
3396
2923
3349
2874
3301
2824
3251
2774
3201
2722
3148
2670
3095
2616
3039
2561
2983
Normal
Emerg
0
2.533
160
160
3209
3627
3166
3585
3121
3542
3076
3499
3030
3454
2984
3408
2936
3361
2888
3313
2839
3264
2789
3213
2738
3161
2686
3108
Normal
Emerg
0
2.533
170
170
3307
3721
3265
3681
3222
3640
3179
3599
3135
3556
3091
3513
3046
3468
3000
3423
2953
3376
2905
3328
2857
3279
2807
3229
Normal
Emerg
0
2.533
180
180
3403
3813
3362
3775
3321
3736
3280
3697
3238
3656
3195
3615
3152
3572
3108
3529
3064
3485
3018
3439
2972
3393
2925
3345
DMS #590159
-15
-10
Planning Rating Summer
Page 46 of 47
Originally Issued: 10/09
Revised: 03/01/10
References
T72 189-4 “Effect of Elevated Temperature on the Strength of Aluminum Conductors” by J. R.
Harvey
IEEE Paper C72 188-6 “Effect of Elevated Temperature on the
“Performance of Conductor Accessories” by W. B. Howett and T. E.
Simpkins
Southwire “Overhead Conductor Manual,”2007
IEEE Std. 738-2006“IEEE Standard for Calculating the Current - Temperature Relationship of Bare
Overhead Conductors"
PJM Circuit Rating Review, C&TPS Report to P&E Committee, May 1986
DMS #590159
Page 47 of 47
Originally Issued: 10/09
Revised: 03/01/10