INDEX
INTRODUCTION................................................................................................................................................... 2
EXAMPLE OF AN OVERHEAD LINES........................................................................................................... 3
GENERAL INFORMATION................................................................................................................................ 5
BARE ANNEALED COPPER CONDUCTORS........................................................................................... 7
AAC – ALL ALUMINUM CONDUCTORS..................................................................................................... 8
ACSR – ALUMINUM CONDUCTORS STEEL REINFORCED............................................................... 9
AAAC – ALL ALUMINUM ALLOY CONDUCTORS..................................................................................11
PVC INSULATED HARD DRAWN COPPER CONDUCTORS.............................................................12
PVC INSULATED HARD DRAWN ALUMINUM CONDUCTORS........................................................13
QUADRUPLEX 0.6/1KV...................................................................................................................................14
ELECTRICAL PARAMETERS OF THE CABLES.......................................................................................15
CURRENT RATING............................................................................................................................................17
CONVERSION TABLE......................................................................................................................................18
PACKING..............................................................................................................................................................19
SELECTION FORM...........................................................................................................................................20
OVERHEAD LINES | 1
INTRODUCTION
Energya Cables SA extensive line of copper and aluminum aerial lines, including bare and weather
resistant insulated conductors, serve the total distribution and transmission needs of electric utilities, rural electric co-ops and the public power market for both traditional and renewable energy
sources.
Its distinct advantage is portrayed in its relentless commitment to quality, which is complemented by
its superior technical expertise and extensive manufacturing capabilities. Energya Cables SA Overhead Lines are manufactured based on customer’s standards, such as SEC or ARAMCO, or on
international standards such as IEC, BS.
Overhead Lines are bare conductors that are used for earthing electrical systems (where soft drawn
copper is used) and in transmission/distribution of high voltage electricity (where hard drawn copper
and aluminum are used). Examples include:
• AAC (All Aluminum Conductors) used in short spans
• AAAC (All Aluminum Alloy Conductors)
• ACSR (Aluminum Conductor Steel Reinforced) used in large spans
In this catalogue, we cover all technical aspects of Energya Cables SA Overhead Lines. We included
Design Considerations such as conductor size, number of wires, and wire diameter, cables electrical
parameters such as conductor DC resistance are included as well.
2 | OVERHEAD LINES
EXAMPLE OF AN OVERHEAD LINES
OVERHEAD LINES | 3
STANDARDS
International Standards
International, European, and UK standards for bare overhead conductors at the
time of publication are as follows:
BSI: British Standards Institution.
IEC: The International Electrotechnical Commission
ASTM: American Society for Testing and Materials.
DIN: The German Institute for Standardization.
4 | OVERHEAD LINES
GENERAL INFORMATION
Selecting a Power Line
The choice of conductor is determined by current rating and stringing conditions (span length, sag,
everyday stress, ambient temperature and wind velocity, and worst case conditions of wind and
ice). Conductor characteristics such as strength to weight ratio, ultimate tensile strength, modulus
of elasticity, area, coefficient of linear expansion, AC resistance will determine the most suitable
conductor.
• AAC – All Aluminum Conductor is made up of one or more strands of hard drawn 1350 Aluminum Alloy. Because of its relatively poor strength-to-weight ratio, AAC has had limited use
in transmission lines and rural distribution because of the long spans utilized. However, AAC
has seen extensive use in urban areas where spans are usually short but high conductivity
is required. The excellent corrosion resistance of aluminum has made AAC a conductor of
choice in coastal areas.
• ACSR – Aluminum Conductor Steel Reinforced consists of a solid or stranded steel core
surrounded by one or more layers of strands of 1350 aluminum. The high-strength ACSR 8/1,
12/7 and 16/19 strandings, are used mostly for overhead ground wires, extra long spans, river
crossings, etc. The inner core wires of ACSR may be of zinc coated (galvanized) steel.
• AAAC – A high strength Aluminum-Magnesium-Silicon Alloy cable was developed to replace
the high strength 6/1 ACSR conductors. This alloy conductor offers excellent electrical characteristics, excellent sag-tension characteristics and superior corrosion resistance to that of
ACSR.
Equivalent aluminum alloy conductors have approximately the same ampacity and strength as their
ACSR counterparts with a much improved strength-to-weight ratio, and also exhibit substantially
better electrical loss characteristics than their equivalent single layer ACSR constructions. The thermal coefficient of expansion is greater than that of ACSR.
As compared to ACSR, AAAC’s lighter weight, comparable strength and current carrying capacity,
lower electrical losses and superior corrosion resistance have given this conductor wide acceptance as a distribution conductor. It has found limited use, however, as a transmission conductor.
• Plain Annealed Copper – Fixed installation conductor stranding is used in multicore cables,
conduit wire, and earthing conductors where they are used for earth mats and the earthing
conductor between earth rods. Alternative conductor strandings offer the maximum flexibility
available in the conductor sizing, but this comes with increased cost. A range of conductor
stranding and make up between these two is available on request.
OVERHEAD LINES | 5
• Plain Hard Drawn Copper – These conductors are a combination of imperial and metric
sizes. Their main use is bare aerial conductors because of lower elongation and increased
tensile rating compared to annealed copper conductors. They can also be used in earth mats,
and as earthing conductors between earth rods.
• Covered Aerial Conductors-Cu – Aerial service cable to domestic and small to medium
size commercial and industrial installations. Extra UV stability due to increased carbon black
sheath
• Covered Aerial Conductors-AL – For aerial reticulation to residential and rural areas where
reliability, safety and low installation costs are required. Reduction of bushfire hazards and frequent tree lopping in uncleared areas. Incorporates UV stabilization for continuous exposure
to sunlight.
Standards
The cables described in this catalogue are all standard types, and their performance has been
proved in operation. Construction and tests are in accordance with the recommendations of lEC
publications, ASTM, DIN, and BS where applicable.
Power cables in accordance to other standards can be manufactured upon customer’s request.
Variation in Production parameters and Delivery Options
• The provided cables data are approximate
• Delivery length tolerance is ± 5% and subject to manufacturing tolerance
• Other sizes are available upon request
6 | OVERHEAD LINES
BARE ANNEALED COPPER CONDUCTORS
Standard :
Conductor :
Packing
:
IEC 60228
Soft annealed stranded copper wires
Coils or Non returnable wooden drums as per
customer requirements
TECHNICAL INFORMATION
P.S. Conductors based on other standards are available upon request.
Applications: Fixed installation conductor stranding is used in multicore cables, conduit wire,
and earthing conductors where they are used for earth mats and the earthing conductor between
earth rods.
Alternative conductor strandings with greater flexibility are available on request.
OVERHEAD LINES | 7
AAC – ALL ALUMINUM CONDUCTORS
Standard :
Conductor :
Packing
:
DIN 48201- Part 5, BS 215
Hard drawn stranded aluminum wires
Non returnable wooden drums as per customer
requirements
TECHNICAL INFORMATION
P.S. Conductors based on other standards are available upon request.
Applications: Stranded bare All-Aluminum 1350 Conductors (AAC) are used in overhead line
installations where design parameters do not require the higher strength or temperature ratings
provided by ACSR, ACSS or other type conductors.
8 | OVERHEAD LINES
ACSR – ALUMINUM CONDUCTORS STEEL REINFORCED
Standard :
Conductor :
Packing
:
ASTM B 232
A center galvanized steel wire(s) and Hard drawn
stranded aluminum wires*
Non returnable wooden drums as per customer
requirements
TECHNICAL INFORMATION
* When required, Grease may be applied for anti-corrosion purposes conductors based on other standards
are available upon request.
Applications: Aluminum Conductors, Steel Reinforced (ACSR) are extensively used for overhead distribution and transmission lines.
OVERHEAD LINES | 9
ACSR – ALUMINUM CONDUCTORS STEEL REINFORCED
TECHNICAL INFORMATION
P.S. When required, Grease may be applied for anti-corrosion purposes conductors based
on other standards are available upon request.
10 | OVERHEAD LINES
AAAC – ALL ALUMINUM ALLOY CONDUCTORS
Type
:
Standard :
Conductor :
Packing
:
AL ALLOY TYPE A as per IEC 60104
IEC 61089
AL-Magnesium- Silicon alloy
Non returnable wooden drums as per
customer request requirements
TECHNICAL INFORMATION
P.S. Conductors based on other standards (ASTM B399, BS 50182…) are available upon request.
Applications: AAAC Aluminum Alloy Conductors are extensively used for overhead distribution and transmission lines adjacent to ocean coastlines where there can be a problem of corrosion in the steel of an ACSR construction.
The Aluminum Alloy Conductors are used in place of single layer ACSR conductors to reduce
power losses in overhead distribution and transmission lines. The inductive effect of the ACSR’s
steel core is eliminated, hence increasing the operating efficiency of the line.
OVERHEAD LINES | 11
HD CU/PVC – PVC INSULATED HARD DRAWN
COPPER CONDUCTORS
Type
:
Standard :
Conductor :
Insulation :
Packing
:
Type 8 (or Type 16)*
BS 6485
Hard drawn standed copper wires
PVC compound**
Non returnable wooden drums as per
customer requirements
TECHNICAL INFORMATION
P.S. Insulation color is black for type 8, green for type 16, or other colors.
Type 16 (increase in insulation thickness) is also available.
Conductors based on other standards are available upon request.
Applications: Aerial service cable to domestic and small to medium size commercial and industrial installations. It has Extra UV stability due to increased carbon black sheath.
12 | OVERHEAD LINES
HD AL/PVC – PVC INSULATED HARD DRAWN
ALUMINUM CONDUCTORS
Type
:
Standard :
Conductor :
Insulation :
Packing
:
Type 8 (or Type 16)*
BS 6485
Hard drawn standed copper wires
PVC compound**
Non returnable wooden drums as per
customer requirements
TECHNICAL INFORMATION
P.S. Insulation color is black for type 8, green for type 16, or other colors.
Type 16 (increase in insulation thickness) is also available.
Conductors based on other standards are available upon request.
Applications: Aerial service cable to domestic and small to medium size commercial and industrial installations. It has Extra UV stability due to increased carbon black sheath.
OVERHEAD LINES | 13
HD AL – QUADRUPLEX 600V
Type
:
Standard :
Conductor :
Neutral
:
Insulation :
Packing
3 insulated phase conductor + 1 bare neutral
NEMA S66-524/IEC 60228
HD AL
HD AL
XLPE + 2.5% Carbon Black
Non-returnable wooden drums as per
customer request
TECHNICAL INFORMATION
P.S. Conductors based on other standards are available upon request.
Other type of neutrals may be used, ACSR/AW for example.
Applications: Quadruplex Service Drop Cable is intended to deliver 4-wire three phase power
from the secondary power line or pole-mounted transformer to the service-entrance conductors
at the user’s building or other structure. It may also be used as pole line secondary with service
splices at the pole or in mid-span.
14 | OVERHEAD LINES
Electrical Parameters Of The Cables
DC Resistance of Conductor
The Maximum DC resistance values of conductors at 20ºC are as per “IEC 60228” standard.
DC resistance per unit length of the conductor at other conductor temperature is given by:
R = Ro [ 1 + α20ºC (t – 20ºC)]
Where :
R = DC resistance at temperature t ºCΩ/km
Ro = DC resistance at temperature 20ºC Ω/km (given in the relative tables for each type of cable)
t = Conductor temperature ºC
α20ºC = Temperature coefficient at 20ºC 1/ºC
For copper conductor α20ºC = 0.00393
For aluminum conductor α20ºC = 0.00403
A.C. Resistance of Conductor
The AC Resistance per unit length of the conductor (effective resistance) at its maximum operating
temperature is made up of the DC resistance at this temperature and the extra resistance which
takes into account additional losses caused by the current displacement in the conductor (skin effect, proximity effect). The AC resistance is given in the relative tables for each type of cable.
Inductance
The values of the inductance for both multi cores and three single core cables have been calculated
based on the following equation:
L = K+0.2 ln (2S /d) (mH/km)
Where:
K = a constant relating to the conductor formation (mH/km).
d = the conductor diameter (mm)
S = axial spacing between conductors for cables in trefoil formation (mm)
= 1.26 x axial spacing between conductors for cables in flat formation (mm)
The values for inductance of single core cables has been calculated based on one cable diameter
between cables in flat formation.
Operation Capacitance
The values of operating capacitance for cables has been calculated based on the following presumption:
C=
εr
18 In (D / d)
(µf/km)
Where :
εr = Relative permittivity of insulation
D = External diameter of insulation (mm)
d = Conductor diameter (mm)
OVERHEAD LINES | 15
Operation Temperature for XLPE Insulated Cables
90ºC for continuous normal operation.
105ºC for emergency overload conditions.
250ºC for short circuit conditions.
Voltage Drop
When current flows in a cable conductor, there is a voltage drop between the ends of the conductor
which is the product of the current and the impedance . The following equations should be used to
calculate the voltage drop:
1 – Single phase system
Vd = 2(R cosφ + X sinφ) (Volt/amp/meter)
2 – Three phase system
Vd = √3(R cosφ + X sinφ) (Volt/amp/meter)
Where:
Vd = Voltage drop (V/Am)
R = AC resistance of conductor at a maximum conductor temperature (Ω/km)
X = Inductive reactance of cable (Ω/km)
Cosφ = power factor of load
* Voltage drop data for L.V cables are tabulated in tables 16 to 23.
Cable Short Circuit Capacity
The permissible short-circuit as presented in tables 12 to 15 are calculated in accordance with IEC
724, which are based on the following conditions:
1 – Short circuit starts from the maximum operating temperature.
2 – Maximum temperature during short circuit XLPE = 250ºC, PVC =160ºC
3 – Maximum short circuit current duration is 5 seconds.
The short-circuit current (I) shall be calculated from the formula:
I2 =
K 2 x S2
T
x In
θ1 + ß
θ2 + ß
Where:
I = Short circuit current (A)
T = Duration of short circuit (Second)
K = Constant for the material of the conductor
S = Area of conductor (mm2)
θ1 = Final temperature (ºC)
θ2 = Initial temperature (ºC)
ß = Reciprocal of the temperature coefficient of resistance (α) of the conductor.
16 | OVERHEAD LINES
CURRENT RATING
Recommendations For Current Rating
The current rating of overhead lines is defined by the maximum intensity of current (in Amperes),
which can flow continuously through the cable, under permanent loading conditions without any risk
in changing the physical properties of the line.
The Current rating capacities of overhead lines are calculated according to IEC 61597 and IEEE
STD 738-2006. In order to calculate them, the following data must be provided at the time of request for information:
•
Speed of air stream (in m/s) and direction of blow at conductor
•
Ambient temperature (in °C)
•
Intensity of solar radiation at the site of installation (w/m2). Or the geographic coordinates
and elevation of the location of installation can be provided instead.
OVERHEAD LINES | 17
CONVERSION TABLE
Multiply
by
to obtain
WEIGHT – Imperial
Ounces ........................................... 28.3495 grams
Pounds (Av) ................................... 453.59 grams
Pounds (Av) ................................... 0.45359 kilograms
Tons (short) ...................................
907.19 kilograms
Tons (long) ..................................... 1016.05 kilograms
WEIGHT – Metric
Grams ............................................ 0.03527
Grams ............................................ 0.002205 Kilograms ......................................
35.274
Kilograms ......................................
2.2046
Kilograms ...................................... 0.001102
Kilograms ..................................... 0.0009842
ounces
pounds
ounces
pounds
tons (short)
tons (long)
MISCELLANEOUS – Imperial
Pounds per 1000 feet ............... 1.48816
Pounds per mile .......................... 0.28185
Pounds per square inch ............ 0.0007031 Pounds per square inch ............ 0.07031
Feet per second ..........................
18.288
Feet per second .......................... 1.09728
Mils per hour ................................ 1.60935
Ohms per 1000 feet .................. 3.28083
Ohms per mile ............................. 0.62137
Decibels per 1000 feet ............. 3.28083
Decibels per mile ........................ 0.62137
Decibles ........................................
0.1153
kilograms per kilometer
kilograms per kilometer
kilograms per square millimeter
kilograms per square centimeter
meters per minute
kilometers per hour
kilometers per hour
ohms per kilometer
ohms per kilometer
decibels per kilometer
decibels per kilometer
nepers
MISCELLANEOUS – Metric
Kilograms per kilometer ............
Kilograms per kilometer ............
Kilograms per square millimeter
Kilograms per square centimeter
Grams per cubic centimeter ....
Meters per minute ......................
Kilometer per hour .....................
Kilometer per hour .....................
Ohms per kilometer ...................
Ohms per kilometer ...................
Decibels per kilometer ..............
Decibels per kilometer ..............
pounds per 1000 feet
pounds per mile
pounds per square inch
pounds per square inch
pounds per cubic inch
feet per second
feet per second
miles per hour
ohms per 1000 feet
ohms per mile
decibels per 1000 feet
decibels per mile
0.67197
3.54795
1422.34
14.2234
0.03613
0.05468
0.91134
0.62137
0.3048
1.6093
0.3048
1.6093
TEMPERATURE
ºFahrenheit ................................... 5/9 (ºF)-32 ºCelsius
ºCelsius .................................... 9/5 (ºC) + 32 ºFahrenheit
18 | OVERHEAD LINES
Multiply
by
LENGTH - Imperial
Mils ...............................................
Mils ...............................................
Inches ..........................................
Inches ..........................................
Inches ..........................................
Feet ..............................................
Feet ..............................................
Feet (thousands of) ..................
Yards ............................................
Mils ...............................................
0.001
0.0254
1000
25.40
2.54
30.48
0.3048
0.3048
0.9144
1.6093
to obtain
inches
millimeters
mils
millimeters
centimeters
centimeters
meters
kilometers
meters
kilometers
LENGTH – Imperial
Millimeters .................................. 39.37
Millimeters ................................. 0.03937
Centimeters .............................. 0.3937
Centimeters ........................... 0.032808
Meters ........................................ 39.37
Meters ........................................ 3.2808
Meters ........................................ 1.0936
Kilometers ................................. 3280.83
Kilometers ................................. 0.62137
mils
inches
inches
feet
inches
feet
yards
feet
mils
AREA – Imperial
Square mils ............................... 1.2732
Square mils ............................ 0.000001 Circular mils ...........................
0.7854 Circular mils ................. 0.0000007854
Circular mils ...................... 0.00050657 Square inches ......................... 1000000 Square inches ......................... 1273240 Square inches ......................... 645.16 Square inches ......................... 6.4516 Square inches ......................... 0.09290 Square inches ......................... 0.8361
circular mills
square inches
square mils
square inches
square millimeters
square mils
circular mils
square millimeters
square centimeters
square meters
square meters
AREA – Metric
Square millimeters .................
Square millimeters .................
Square centimeters ...............
Square meters ........................
Square meters ........................
circular mills
square inches
square inches
square feet
square yards
1973.52
0.00155
0.155
10.7638
1.19599
VOLUME - Imperial
Cubic inches .......................... 16.38716
Cubic feet ............................... 0.028317
cubic centimeters
cubic meters
VOLUME – U.S.
Quarts (liquid) ............................ 0.9463
Gallaons ...................................... 3.7854
cubic centimeters
cubic meters
VOLUME – Metric
Cubic centimeters ..................
Cubic meters ...........................
Litres ..........................................
Litres ..........................................
cubic inches
cubic feet
quarts (Liquid U.S.)
gallons (U.S.)
0.06102
35.3145
1.05668
0.26417
PACKING
International practice is to supply cables
on wooden drums or as appropriate plastic
spools. At the customers request we will also
supply steel drums for improved on-site performance and handling.
The finished drums may be – when requested
by our customer – closed with a continuous
lagging with a wood having approximate thickness 2.00 mm.
OVERHEAD LINES | 19
SELECTION FORM (Overhead Lines)
This form needs to be filled in order to help Energya Cables SA prepare the right quotation:
20 | OVERHEAD LINES