D800053X052
December 2016
Quick Start Guide for DeltaV Power, Grounding,
and Surge Suppression
© Emerson Process Management 1996 - 2016. All rights reserved. For Emerson Process Management trademarks and service marks,
go to Emerson Process Management Trademarks and Service Marks. All other marks are property of their respective owners. The
contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their
accuracy, they are not to be construed as warranties or guarantees, expressed or implied, regarding the products or services
described herein or their use or applicability. All sales are governed by our terms and conditions, which are available on request. We
reserve the right to modify or improve the design or specification of such products at any time without notice.
See the CE statement in Chapter 1.
Emerson Automation Solutions
1100 W. Louis Henna Blvd.
Round Rock, TX 78681
Contents
Contents
Chapter 1
Welcome ....................................................................................................................... 1
DeltaV version this manual supports ....................................................................................................... 1
Related DeltaV information .................................................................................................................... 1
CE statement .......................................................................................................................................... 2
Warning, Caution, Important, and Note ................................................................................................. 2
Chapter 2
Introduction .................................................................................................................. 5
Chapter 3
The basic premise .......................................................................................................... 7
Chapter 4
The reasons for grounding ............................................................................................. 9
Chapter 5
Ground cable sizing ......................................................................................................11
Chapter 6
Establishing and maintaining clean power ................................................................... 13
Clean power options ............................................................................................................................. 17
Single AC source ....................................................................................................................................18
Two AC sources ..................................................................................................................................... 19
Chapter 7
DeltaV power and grounding options ...........................................................................21
S-series ..................................................................................................................................................21
CHARMs ................................................................................................................................................ 27
SIS ......................................................................................................................................................... 32
Power supply configuration ....................................................................................................... 34
Incorporating M-series SLS into S-series .....................................................................................36
Multiple Distributed Enclosures: Power and Grounding Schemes .......................................................... 38
Floating AC and high-resistance ground ................................................................................................ 42
Chapter 8
Grounding topologies .................................................................................................. 45
Star or single-point ground ....................................................................................................................45
Mesh star ground network .................................................................................................................... 46
Hybrid star mesh ground network ......................................................................................................... 48
Appendices and reference
Appendix A
Interference and transients .......................................................................................... 49
Static (capacitive) coupling ................................................................................................................... 49
Voltage differentials ..............................................................................................................................50
Inductive coupling .................................................................................................................................51
Appendix B
High integrity ground systems ..................................................................................... 53
Highest integrity systems have shields connected to chassis ground .....................................................53
Appendix C
Checklists for verifying site ground .............................................................................. 55
Site ground verification checklists ......................................................................................................... 55
Checklists ..............................................................................................................................................55
Good engineering practices for general systems ........................................................................56
Environmental conditions ..........................................................................................................57
Power and grounding connections ............................................................................................ 58
Power and grounding connections with triad .............................................................................60
General field device installation ................................................................................................. 61
i
Contents
I/O wiring (conventional, HART, serial, and bus types) ............................................................... 63
Enclosures ................................................................................................................................. 65
AC power system and distribution ............................................................................................. 68
DC power system and distribution ............................................................................................. 69
DeltaV controllers ......................................................................................................................71
List of equipment used .............................................................................................................. 73
Appendix D
ii
References ................................................................................................................... 75
Welcome
1
Welcome
Topics covered in this chapter:
•
•
•
•
DeltaV version this manual supports
Related DeltaV information
CE statement
Warning, Caution, Important, and Note
This manual is a quick start guide for providing power, grounding, and surge suppression
for Emerson's new CHARM and S-series products. Parts of this manual also apply to DeltaV
M-series products as well. More specifically, this manual explains how to properly design
and prepare control system electrical power and ground networks before you install your
DeltaV system. Applying the information in this manual saves time and expense by
significantly increasing the reliability of your control system and by making your system
easier to start up and maintain.
The power and grounding techniques described in this manual are based on best
engineering practices and industry standards. In addition to this manual, you may need
other DeltaV and industry publications to obtain complete information for preparing your
site. References to related industry standards can be found at the end of this document.
DeltaV version this manual supports
The information in this manual applies to all versions of DeltaV systems; however the focus
of this manual is on S-series equipment. Periodically, this manual is updated to incorporate
site preparation information for the newest DeltaV products and to add information based
on user feedback. To make sure you have the latest edition, contact your Emerson Process
Management local business partner or field sales office (LBP/FSO).
Note
Because this manual covers all DeltaV versions and various OEM products, it often uses generic
symbols in drawings instead of exact product representations. See DeltaV and OEM manuals for
exact representations.
Related DeltaV information
Additional information is included on product DVDs, on Emerson Process Management
web sites, and in printed manuals. Your Emerson Process Management local business
partner or field sales office (LBP/FSO) can help you obtain the information you need.
Site Preparation and Design for DeltaV Digital Automation Systems covers power and
grounding for M-series and previous releases of SIS products. It also contains valuable
information such as EMI, ESD, and environmental precautions.
1
Welcome
DeltaV product data sheets include descriptions, features, benefits, specifications, and
ordering information that are of particular importance to site preparation. Product data
sheets are available from LBP/FSO.
DeltaV Books Online and context-sensitive help are embedded in DeltaV system software
and are viewable after the software has been installed. Manuals needed to install and start
up DeltaV products are shipped with the software in Adobe PDF format on the DeltaV
Documentation Library disk. In addition to this manual, manuals included on the DeltaV
Documentation Library disk include:
•
DeltaVTM S-series and CHARMs Hardware Installation describes installation procedures,
including details of screw terminal connections on power supplies and carriers.
•
DeltaV TM S-series and CHARMs Hardware Reference contains specifications, wiring
diagrams, dimensions, and other reference information for S-series and CHARMs
hardware components.
•
Getting Started with Your DeltaV TM Software describes startup and operating
procedures.
•
Fieldbus Installations in a DeltaV TM Distributed Control System describes planning for
installing FOUNDATION Fieldbus systems.
•
Installing Your DeltaV SIS TM Process Safety System Hardware describes installation,
including details of screw terminal connections and wiring for smart logic solvers,
SISNet repeaters, and other safety instrumentation hardware.
•
DeltaV SISTM Process Safety System Safety Manual describes how a DeltaV Safety
Instrumented System must be used for it to function as a safety instrumented
system.
•
DeltaV SISTMAccessories Installation and Safety Manual describes how to properly
install the Safety Relay Module and the Voltage Monitor Module.
Printed versions of many of these manuals can be ordered from your LBP/FSO. Users with
Guardian or Foundation Support can access the manuals from the support website in PDF
format.
CE statement
If you intend to have your DeltaV system certified for compliance to appropriate European
Union directives, it must be installed in accordance with procedures described in the
manual DeltaV S-series and CHARMs Hardware Installation.
Warning, Caution, Important, and Note
A Warning, Caution, Important, or Note identifies helpful or critical information. The type
of information included in each is:
2
Welcome
WARNING!
Warnings are installation, operation, or maintenance procedures, practices, conditions,
statements, and so forth, which if not strictly observed, may result in personal injury or loss of
life.
CAUTION!
Cautions are installation, operation, or maintenance procedures, practices, conditions,
statements, and so forth, which if not strictly observed, may result in damage to, or
destruction of, equipment or may cause long term health hazards.
Important
Information notices are installation, operation, or maintenance procedures, practices, conditions,
statements, and so forth, which if not observed, may result in improper control system operation.
Note
Notes contain installation, operation, or maintenance procedures, practices, conditions, statements,
and so forth, which alert you to important information which may make your task easier or increase
your understanding.
3
Welcome
4
Introduction
2
Introduction
The information in this document helps you to properly connect power and ground to
Emerson's CHARMs, S-series, and M-series products. For more information on other
aspects of site preparation please refer to the Site Preparation and Design for DeltaV Digital
Automation Systems.
We realize that not all applications require the same level of grounding. In particular, sites
that are mission critical (for example, pharmaceutical batch processes and nuclear power
monitoring),require the highest level of power, ground, and surge integrity and
protection.
5
Introduction
6
The basic premise
3
The basic premise
All of the recommendations in this document are based on good engineering practice and
apply to any control system. The following principles provide a foundation for system
design with respect to mitigating interference issues through power and grounding.
•
Power, ground, and surge should always be considered together because they
frequently interact. A system where power, ground, and surge suppression work in
unison provides the most stable system.
•
There is not a "magic hole" that we can dump all of our unwanted interference into.
However by establishing a stable ground reference (preferably 1 Ω to 3 Ω) for the
control system, voltage events such as those caused by facility faults, dramatic load
changes, or lightning that affect one area of the ground system will not adversely
cause issues with the control system's ground reference.
•
Noise (interference) always wants to return to its source following the path of least
resistance (Ohm's law)
If differences occur between this manual and local or regional codes and regulations,
codes and regulations take precedence.
7
The basic premise
8
The reasons for grounding
4
The reasons for grounding
•
Safety ground (protective earth) — protects personnel from injury resulting from
defective supply feeds. For example, if the insulation of the line side of a 120 VAC
power conductor becomes frayed, causing the conductor to be in direct contact
with a properly grounded metal enclosure, a protective interrupt, such as a fuse or
circuit breaker, opens. The ground conductor must be sized as large as the
maximum AC conductor feeding the load. This conductor should follow the same
path as the line conductors to their source, that is, first disconnect or separately
derived source.
•
High frequency ground — ground systems that improve signal integrity by
reducing noise caused by machinery such as variable speed drives, welders, or
commutated DC motors. Interference and transients from other instrumentation
and equipment is also greatly reduced with a properly constructed high frequency
ground system. Skin effect causes high frequency signals to travel closer to the
surface of conductors. For this reason only the outermost part of cables actually
carry the high frequency interference. For example, a 500 KHz signal uses 100% of
the copper in a 33 AWG wire, but only 36% of the copper in a 19 AWG wire. High
frequency with respect to control systems often encompasses a broad band of
frequencies starting as low as 10 kHz.
•
Stable DC reference ground — A low impedance ground (1 Ω to 3 Ω between the
ground system—triad or plant grid—and earth) maintains the control system at a
stable reference. Utility power and lightning systems should have their own
grounding systems. For safety reasons all grounds shall be connected together.
However, there is finite impedance interconnecting each ground system. There are
also impedance variations between all points of the same system. When a disruptive
event occurs, a short duration voltage gradient is established at the location where
the fault makes contact with the localized ground. By assuring that the control
system has a low impedance to its DeltaV Instrument Ground (DIG), events that
occur in one area of the ground system (typically due to lightning, load shifting, or
faulty utilities) that cause a gradient elevation proximal to it does not have as
significant an effect on the DeltaV Instrumentation Ground (DIG) potential.
•
Lightning protection — protects property and personnel from lightning strikes.
•
Lightning mitigation — protects equipment from induced energy as a result of
lightning. This is accomplished through the interconnection and close proximity of
all of the DeltaV grounding systems. All metal enclosures are connected to the
safety ground system. Separately derived systems, such as isolation transformers
and UPSs, should be as close to the DeltaV systems as possible. Case studies have
shown that induced energy as a result of lightning strikes has disrupted and even
damaged instrumentation equipment due to variance in ground potentials at
multiple locations. By keeping all metal as closely interconnected as possible with
the safety ground system any induced voltage quickly equalizes. This goal is realized
by multiple eddy current paths, minimizing the need for any single conductor to
shunt the equalization current.
9
The reasons for grounding
10
Ground cable sizing
5
Ground cable sizing
DeltaV is a ground referenced system. To maintain high integrity it is important that
careful consideration be paid to ground conductor sizing. The original site preparation
manual, Site Preparation and Design for DeltaV Digital Automation Systems, lists some typical
methods of connecting grounding networks. More grounding networks can be found in
the section of this document on Grounding Topologies. Typically for large high-integrity
systems, shields are connected to the chassis ground bar. One of the most cost efficient
grounding method uses a star topology with larger conductor sizes at the sections located
a greater distance from the cabinets. The following tables are applicable for all DeltaV
products. Table 5-1 lists the appropriate wire size with respect to the distance between a
cabinet and the closest ground bar or between individual ground bars. Cable sizes are
determined based on the number of I/O points associated with that particular section of
cable. The overall distance from an enclosure to the earthing point at the DeltaV
Instrument Ground (DIG) should not exceed 300 feet. The braided cable in Table 5-2 may
be used as an alternative as shown in Table 5-3 for the cable in Table 5-1. Single enclosures
or a group of adjacent enclosures with a relatively small number of I/O points may connect
the chassis ground and the DC ground buses together at the cabinet provided the wire
size, distances, and I/O points are within the specifications listed in Table 5-4.
Table 5-1: Ground wire sizing
Cable length (ft)
I/O points
10
25
50
100
300
64
8 AWG
8 AWG
8 AWG
6 AWG
2 AWG
128
8 AWG
8 AWG
6 AWG
2 AWG
1/0
256
8 AWG
6 AWG
2 AWG
1/0
2/0
512
6 AWG
2 AWG
1/0
2/0
3/0
1024
2 AWG
1/0
2/0
3/0
4/0
2048
1/0
2/0
3/0
4/0
---
4096
2/0
3/0
4/0
---
---
8192
3/0
4/0
---
---
---
Table 5-2: Flat-braided PVC-insulated cable alternative
New England Wire Technologies number
Description
Certification
N30-36T-762-2ULG
48-22-36 TINNED COPPER FLAT UL AWM 1680 105C, VNS
BRAID
N30-30T-652-2UL
48-22-36 TINNED COPPER FLAT UL AWM 1680 105C, VNS
BRAID
11
Ground cable sizing
Table 5-3: Braided cable system
I/O
points
Braided cable length (ft)
10
25
50
100
128
N30-36T-762-2ULG
N30-36T-762-2ULG
N30-36T-762-2ULG
N30-30T-652-2UL
256
N30-36T-762-2ULG
N30-36T-762-2ULG
N30-30T-652-2UL
---
512
N30-36T-762-2ULG
N30-30T-652-2UL
---
---
1024
N30-30T-652-2UL
---
---
---
Table 5-4: Single cable length with chassis ground and DC ground connected in
enclosure
Cable length (ft)
12
I/O points
10
25
50
100
64
8 AWG
8 AWG
6 AWG
2 AWG
128
8 AWG
6 AWG
2 AWG
1/0
256
6 AWG
2 AWG
1/0
2/0
512
2 AWG
1/0
2/0
3/0
1024
1/0
2/0
3/0
4/0
Establishing and maintaining clean power
6
Establishing and maintaining clean
power
Topics covered in this chapter:
•
•
Clean power options
Single AC source
•
Two AC sources
To operate your DeltaV system at the highest level of integrity (that is, to maintain the
system with the least amount of disruptive events due to power anomalies) a properly
designed power conditioning system should be considered.
Clean-power with respect to alternating current used to power bulk supplies is a term that
describes the sinusoidal power that maintains its characteristics with both linear and nonlinear loads. Some commonly used standards which address power quality are:
•
IEEE Recommended Practice for Monitoring Electric Power Quality
•
IEEE Recommended Practices and Requirements for Harmonic Control in Electrical Power
Systems
•
IEC 61000-3-11 Electromagnetic compatibility (EMC) Limitations of voltage changes,
voltage fluctuations and flicker in public low voltage supply systems
•
IEC 61000-3-12 Electromagnetic compatibility (EMC) Limits for harmonic currents
produced by equipment connected to public low voltage systems
Tables Table 6-1 and Table 6-2 list the most prevalent factors that influence the quality of
power. Common causes for power quality issues with corresponding recommendations for
corrective measures can also be found in the tables.
Important
Any three-phase source, such as transformer or UPS, providing power to a DeltaV system must only
power DeltaV products, safety systems, or the control system. Therefore, no VFDs, HVAC, motors,
fans, compressors, ballasts, and so on shall be connected to any output phase of a transformer or
UPS that is also used to power the DeltaV system.
Table 6-1: Potentially disruptive power issues typically solved with a UPS
Type of interference
Possible effect
Interruptions
DeltaV restart
Common cau- Preventive
ses
measures
Utility faults,
UPS
load switching,
breaker trips,
or equipment
failures
Comment
DeltaV systems powered with
Emerson bulk power supplies
are able to withstand power interruptions up to 20 ms.
13
Establishing and maintaining clean power
Table 6-1: Potentially disruptive power issues typically solved with a UPS (continued)
Type of interference
Possible effect
Common cau- Preventive
ses
measures
Sag
Possible DeltaV
restart if voltage drops below lower power supply limit.
Start-up loads UPS
drawing excessive current,
equipment
faults
DeltaV systems powered with
Emerson bulk power supplies
are able to withstand sags up
to 20 ms.
Undervoltage
Loss of power
to the DeltaV
system.
Utility faults or
load changes
UPS
DeltaV powered with Emerson
bulk power supplies are able to
withstand loss of power up to
20 ms.
Swell
Possible power
supply damage
if voltage remains at increased levels
greater than
power supply
limit.
Loads shifting,
utility faults
UPS
Overvoltage
Possible power
supply damage
if voltage remains at increased levels
greater than
power supply
limit
Loads shifting,
utility faults
UPS
Comment
Table 6-2: Power quality issues solved with high quality UPS
Type of interference
Possible effect
Impulse transient
Impulse transients in excess
of 1500 V may
destroy channel or system if
transient is on
power feeds.
14
Common cau- Preventive measses
ures
Lightning
causing voltage gradients
in excess of
1500 V.
Appropriate surge
protection devices
(SPD) should be
considered. The
SPD should be sized
for the worst surge
area that either the
power or shields
enter.
Comment
Typically, bulk supplies
are certified to have either double or reinforced insulation to
withstand 1500V. The
DeltaV system is protected with transient
voltage suppression to
1500V.
Establishing and maintaining clean power
Table 6-2: Power quality issues solved with high quality UPS (continued)
Common cau- Preventive measses
ures
Type of interference
Possible effect
Oscillatory transient
Data loss with
possible damage.
Overall system Double conversion
response to
UPS with filtering.
impulse or
load switching
from inductive
or capacitive
loads.
EFI/RMI noise
Data loss, system corruption.
Transmitters,
faulty equipment, ineffective grounding, close
proximity to
EMI/RFI
source.
Isolation transformer ( common mode
< 1.5MHz), filter
(normal Node 10
KHz to 10 MHz)
UPS with filtered
output
Notching
Data loss, system corruption.
Variable frequency drives,
welders, lighting.
Filters or UPS with
filtered output.
Harmonics
Overheating
which can
shorten the life
of power supplies.
Non-linear
loads.
Could correct at the
source with Active
harmonic filter, Kfactor transformers, power factor
correction supplies
Comment
Isolate VFD's, Never allow generating devices, such as VFD's, to
use the same power
feed or an adjacent leg
on a three phase system.
A double conversion uninterruptible power supply can also mitigate most power quality
issues.
Isolation transformers are an excellent means to significantly reduce common mode noise,
typically up to 750 KHz. The isolation transformer also allows for a separately derived
source of power that creates a stable ground reference point in close proximity with the
DeltaV system. Filters are a readily-available solution for normal-mode noise reduction in
the range of a few hertz up to 10 MHz. Surge suppressor/filters are also available to
prevent surge voltages from indirect lightning or large upstream power faults from
damaging control equipment in addition to minimizing normal-mode noise. A power
quality evaluation of the site can easily determine the best solution to meet your individual
requirements.
UPSs that supply power to control systems should be double conversion types. Typically,
their input voltage is provided from low voltage (100 VAC to 600 VAC) feeders, with either
15
Establishing and maintaining clean power
single or three-phase power. The AC power from the source is rectified to DC and used as
leveling power to maintain batteries or to supply energy for a flywheel. The inverter stage
produces the AC sine wave output using power from the DC storage section - batteries or a
flywheel. Only use UPSs that reproduce high quality sine waves. Some UPSs produce
modified sine waves that are rich in harmonics and detrimental to control systems.
Important
Any UPS supplying power to the DeltaV system shall be of the double conversion type, with an
inverter stage which produces harmonic free sinusoidal output waveforms. Never use a UPS that
produces modified sine waves.
Most UPSs provide a degree of protection from power failure, power sag, and power
surges. However, some UPSs provide an excellent solution for most of the power quality
issues found in Table 6-2. A bypass transformer with static switchover allowing for UPS
maintenance is either supplied as an integral component or can be connected externally to
the UPS. When selecting the bypass transformer note that if the UPS used is the type which
provides the cleanest power, then a shielded bypass transformer would be a better choice
than a standard transformer.
Some UPSs provide three-phase output power. When using a UPS with a three-phase
output, all phases should be connected only to the control system and to non-interfering
equipment. Never connect one phase to the DeltaV system and another phase to a VFD.
Isolation transformers have been successfully used for many years to supply clean-power
for control systems, medical systems, and computer centers. The Isolation transformer
also provides a location to establish a separately derived ground.
For a comparison of the attenuation benefits for the various degrees of shielding available
see Table 6-3. In addition to the common-mode rejection provided by isolation
transformers, many transformers can be purchased with filters on their output stage. The
filter attenuates the normal-mode noise. Shielded transformers with filtered outputs
provide noise reduction from a few hertz to up to 750 KHz in both common and normal
mode.
Table 6-3: Transformer attenuation
Type of shielding
Attenuation ratio
Typical attenuation
No shield
10:1
12 dB to 20 dB
Single shield
1000:1
50 dB to 60 dB
Double shield
10,000:1
65 dB to 90 dB
Triple shield
100,000:1
90 dB to 120 dB
Most industrial applications share power with a wide variety of devices including large
motors, furnaces, large lighting systems, and HVAC systems. Control applications that can
tolerate disruptive events require little or limited consideration with respect to the Power
Distribution Unit (PDU). However, if the application requires a high degree of consistent
system integrity with minimal disruption, then the proper PDU should be used. Figure 6-1 is
a tool to help determine the most economical and effective configuration for your site's AC
power requirements with respect to interruptions and noise mitigation.
16
Establishing and maintaining clean power
Clean power options
There are a number of ways to provide clean power. To find the correct solution for your
site, follow the flowchart in Figure 6-1 and choose the proper options below.
Figure 6-1: AC power source flowchart
Evaluate
Power needs for
DeltaV Site
Is Power
Failure, Sag, or Surge
present?
No
No
Is Noise, which could
potentially cause disruptive
events, present?
Yes, use a UPS
No
Yes
Is Noise, which could
potentially cause disruptive
events present?
Use UPS(s) with at least
No
Is Power Source
in close proximity
(< 100 m) to DeltaV?
Power Failure
Power Sag
Power Surge
Undervoltage protection
Overvoltage Protection
Yes
No
Is Noise at
Frequencies > 10KHz
a present?
Yes
Yes
Use UPS(s) with
Power Failure
Power Sag
Power Surge
Undervoltage protection
Overvoltage Protection
Line noise elimination
Frequency variation correction
Switching Transient filter
Harmonic Interference filter
Use an Isolation Transformer
and Suppressor/Filter or
Filter in close proximity to
Bulk Supply
Use Transformer or UPS(s)
to Establish a Separately
derived ground reference at
DeltaV DIG
Use an
Isolation Transformer
Or
Use UPS(s) with
Power Failure
Power Sag
Power Surge
Undervoltage protection
Overvoltage Protection
Line noise elimination
Frequency variation correction
Switching Transient filter
Harmonic Interference filter
Chose Number of
AC Sources required
17
Establishing and maintaining clean power
CAUTION!
When NOT using a separately derived ground system with interference levels equal to or lower
than stipulated in EN 61000-3-12 and EN 61000-3-11 and when no noise such as described in
Table 6-1 and Table 6-2 is present, then at no time following the installation of DeltaV shall
interference be permitted if high integrity is desired.
Single AC source
Option A
Highest integrity
•
UPS with the following features:
-
Neutral/ground bond point to establish a separately derived ground reference
-
Power failure, power sag, and power surge protection
-
Capable of regulating under-voltage and over-voltage input power
-
Line noise elimination, frequency variation correction, switching transient filter
harmonic interference filter
•
UPS to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply
•
Bypass isolated transformer with single isolated shielding
•
Power lines in armored cable or metal conduit (optional)
Option B
•
UPS with the following features:
-
Neutral/ground bond point to establish a separately derived ground reference
-
Power failure, power sag, and power surge protection
-
Capable of regulating under-voltage and over-voltage input power
•
UPS to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply (optional if signal shields are not located
in Zone 0 or Zone 1 lightning area)
•
Bypass isolated transformer with single isolated shielding
•
Power lines in armored cable or metal conduit (optional)
Option C
18
•
Isolation transformer
•
Neutral/ground bond point to establish a separately derived ground reference
•
Transformer to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply (optional if signal shields are not located
in Zone 0 or Zone 1 lightning area)
Establishing and maintaining clean power
•
Power lines in armored cable or metal conduit (optional)
Option D (clean-power: AC source <100 m)
•
Surge suppressor/filter prior to bulk supply (optional if signal shields are not located
in Zone 0 or Zone 1 lightning area)
•
Power lines in armored cable or metal conduit (optional)
Option E (clean-power: AC source < 300m)
•
Surge suppressor/filter prior to bulk supply
•
Power lines in armored cable or metal conduit
Two AC sources
Option F
Highest integrity
AC source 1 and 2
•
UPS with the following features:
-
Neutral/ground bond point to establish a separately derived ground reference
-
Power failure, power sag, and power surge protection
-
Capable of regulating under-voltage and over-voltage input power
-
Line noise elimination, frequency variation correction, switching transient filter
harmonic interference filter
•
UPS to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply
•
Bypass isolated transformer with single isolated shielding
•
Power lines in armored cable or metal conduit (optional)
Option G
Highest integrity
AC source 1
•
UPS with the following features:
-
Neutral/ground bond point to establish a separately derived ground reference
-
Power failure, power sag, and power surge protection
-
Capable of regulating under-voltage and over-voltage input power
-
Line noise elimination, frequency variation correction, switching transient filter
harmonic interference filter
•
UPS to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply
19
Establishing and maintaining clean power
•
Bypass isolated transformer with single isolated shielding
•
Power lines in armored cable or metal conduit (optional)
AC source 2
•
Isolation transformer
•
Neutral/ground bond point to establish a separately derived ground reference
•
Transformer to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply
•
Power lines in armored cable or metal conduit (optional)
Option H
AC sources 1 and 2
•
Isolation transformer
•
Neutral/ground bond point to establish a separately derived ground reference
•
Transformer to DeltaV cabinet distance of less than 100 meters
•
Surge suppressor/filter prior to bulk supply
•
Power lines in armored cable or metal conduit (optional)
Option I (clean-power: AC source < 100m)
AC sources 1 and 2
•
Surge suppressor/filter prior to bulk supplies (optional if signal shields are not
located in Zone 0 or Zone 1 lightning area)
•
Power lines in armored cable or metal conduit (optional)
Option J (clean-power: AC source < 300m)
AC sources 1 and 2
20
•
Surge suppressor/filter prior to bulk supplies
•
Power lines in armored cable or metal conduit
DeltaV power and grounding options
7
DeltaV power and grounding options
Topics covered in this chapter:
•
•
•
•
S-series
CHARMs
SIS
Multiple Distributed Enclosures: Power and Grounding Schemes
•
Floating AC and high-resistance ground
DeltaV systems are certified as Separated or Safety Extra Low Voltage (SELV) systems. An
SELV system is "an extra-low voltage system which is electrically isolated from the earth
and from other systems in such a way that a single fault cannot give rise to the risk of
electric shock."(1) Therefore, the DeltaV DC reference ground maintains a stable low noise
reference for the DeltaV signal returns and DC power supply commons.
S-series
Power and grounding of the DeltaV S-series is connected in a manner similar to that of the
M-series products. To convert AC power to the 24 VDC power required for products such
as S-series system power supplies, CHARM I/O Card (CIOC), Safety Integrated System (SIS)
products, and DC field power, a bulk power configuration as shown in Figure 7-1 produces
a high-integrity solution. It is sometimes preferable to create a separate AC to DC panel
that is only accessible by qualified electricians. If an S-series system only contains DC I/O
cards, then field technicians can service the DeltaV panels without working near higher
voltage AC sources.
Typically, the 100 VAC to 230 VAC at 50 Hz or 60 Hz is supplied from power disconnect
panels fed from double conversion uninterruptable power supplies (UPS) or through
isolation transformers to the AC panel. A sufficiently sized disconnect is usually located
prior to each bulk power supply. The two bulk supplies of Figure 7-1 are then fed into a dual
redundancy module to power the DeltaV system bus. If one of the AC feeds fails or one of
the bulk power supplies fails, the redundancy module shifts the load to the remaining
power supply. However, the configuration of Figure 7-1 allows for the possibility of up to
two separate single points of failure:
•
the Dual Redundancy Module
•
if only one DeltaV System Power supply was used as shown in Figure 7-2, then the
single system power supply is also a single point of failure.
All configurations should be weighed from a cost-benefit perspective. Therefore, if the
highest integrity S-series system is required the combination of a power panel as shown in
Figure 7-3 with the redundant S-series system of Figure 7-4 should be used. The two-wide
with redundant system supplies provides injected power allowing the maximum current
for a total of 15 A on an S-series node.
(1) BS 7671:2008 Requirements for Electrical Installations, IET Wiring Regulations 17th Edition, 2008
21
DeltaV power and grounding options
Figure 7-1: Typical power panel for DeltaV systems
Enclosure (A)
DeltaV Power
+24VDC
Enclosure (B)
Fuse TB
Fuse TB
Fuse TB
Enclosure (C)
Enclosure (A)
Field Power
+24VDC
Enclosure (B)
Fuse TB
Fuse TB
Fuse TB
Enclosure (C)
Parallel
Single
Parallel
Single
Chassis
Ground
Parallel
Single
AC/DC
Power
Supply
PS1
AC
100-240V
N L
+24VDC
960W/1440W
+ + – –
Output
Max.
80A
AC/DC
Power
Supply
Dual
Redundancy
Module
Input 1
Input 2
DC 24-28V DC 24-28V
40A
40A
+ – + –
CB1
Parallel
Single
Chassis
Ground
+ –
+ –
AC/DC
Power
Supply
PS2
AC
100-240V
N L
CB2
PS3
+24VDC
960W/1440W
+ + – –
AC
100-240V
N L
+24VDC
960W/1440W
+ + – –
Output
Max.
80A
AC/DC
Power
Supply
Dual
Redundancy
Module
Input 1
Input 2
DC 24-28V DC 24-28V
40A
40A
+ – + –
CB3
PS4
AC
100-240V
N L
+24VDC
960W/1440W
+ + – –
CB4
Primary
AC Power
Secondary
AC Power
PE
Adjacent Enclosure
6 AWG minimum
Enclosure Door
Enclosure PE Ground Lug
Note
The 24 VDC return (-) terminal of the power supplies must be connected to DeltaV DC ground. This is
accomplished as shown in Figure 7-2 from the bused DC ground wire connected to the DC ground
bus.
22
DeltaV power and grounding options
Figure 7-2: S-series power and grounding
Field
Power
… Field Devices as required
+24VDC
DeltaV
Power
+24VDC
Jumper
14
AWG
Jumper
Jumper
Jumper
DC Ground
Chassis Ground
(CG)
14 AWG
Isolated Bus
To DIG
To DIG
Adjacent Enclosure
6 AWG minimum
Enclosure door
Enclosure PE Ground Lug
23
DeltaV power and grounding options
Figure 7-3: High integrity redundant power panel for DeltaV systems
Fuse TB
Primary
DeltaV Power
+24VDC
Fuse TB
Secondary
DeltaV Power
+24VDC
Fuse TB
DeltaV
Field Power
+24VDC
Parallel
Single
Parallel
Single
Parallel
Single
Parallel
Single
Chassis
Ground
+ –
AC/DC
Power
Supply
AC/DC
Power
Supply
PS1
AC
100-240V
N L
AC/DC
Power
Supply
PS2
+24VDC
960W/1440W
AC
100-240V
+ + – –
N L
CB1
CB2
PS3
+24VDC
960W/1440W
+ + – –
AC
100-240V
N L
+24VDC
960W/1440W
+ + – –
Output
Max.
80A
Input 1
Input 2
DC 24-28V DC 24-28V
40A
40A
+ – + –
CB3
Primary
AC Power
Secondary
AC Power
To DIG
24
PE
AC/DC
Power
Supply
Dual
Redundancy
Module
Adjacent Enclosure
6 AWG minimum
Enclosure Door
Enclosure PE Ground Lug
PS4
AC
100-240V
N L
CB4
+24VDC
960W/1440W
+ + – –
DeltaV power and grounding options
Note
The 24 VDC return (-) terminal of the power supplies shall be connected to DeltaV DC ground. This is
accomplished as shown in Figure 7-4 from the DC ground wire connected to the DC ground bus.
25
DeltaV power and grounding options
Figure 7-4: S-series redundant power and grounding
Field Power
+24VDC
Primary
DeltaV Power
+24VDC
14 AWG
14 AWG
Field Devices as required
14 AWG
Secondary
DeltaV Power
+24VDC
Jumper
Jumper
Jumper
Isolated Bus
Chassis Ground
(CG)
14 AWG
DC Ground
To DIG
26
To DIG
Adjacent Enclosure
6 AWG minimum
Enclosure door
Enclosure PE Ground Lug
DeltaV power and grounding options
CHARMs
Because CHARMs are typically used in remote locations they usually have dedicated local
redundant power supplies. If CHARM I/O subsystems are powered from AC sources, the
power must be very clean. This clean-power is usually obtained by isolation transformers
located in close proximity to the CHARM cabinet. It may be advantageous to use UPSs or a
combination of a UPS for the primary power and an isolation transformer for the secondary
power. In addition to the UPS and isolation transformers, surge suppressors can be located
just before each bulk power supply. Most power surges are assumed to originate from
lightning. However, it is estimated that in an industrial environment 80% of disruptive
surges originate from the industrial power and equipment. Figure 7-5 shows one of the
highest integrity CHARM systems with respect to power and ground. The typical distance
between the separately derived AC power source and the CHARM cabinet should be 100
meters or less. To greatly reduce any chance of interfering noise coupling into the powerfeed, use conductive metal conduit or armored cable between the separately derived
source (UPSs or Isolation Transformers) and the CHARM enclosure.
Important
CHARM extender cables DO NOT extend the shield bar from one group of baseplates to the next.
Baseplate shields are connected to the Chassis Ground (CG) using 14 AWG wire from the Address
Plug terminal connection or the end terminator connection point. If extender cables are used and
shielded signal cables are located on baseplates on both sides of the extender cables, separate shield
cables must be connected to the CG bar from each set of baseplates.
27
DeltaV power and grounding options
Figure 7-5: Highest integrity power and grounding for a CHARM enclosure
CHARM Enclosure
DC ok
DC ok
AC/DC
Power
Supply
Isolation
Transformer
AC/DC
Power
Supply
PS1
PS1
AC 100-240V
AC 100-240V
N
Communications with
DeltaV Should be
connected via Fiberoptic cable for distance
exceeding 200 ft.
N
L
L
N
AC Feed 1
G N
G
L
C
N
N
O
O
C
M
L
N
G
G N
Filter/Surge
Suppression
Device
Follow Local
Codes
CB1
L
C
N
N
O
O
C
M
L
N
G
Filter/Surge
Suppression
Device
CB1
Isolation
Transformer
N
AC Feed 2
G
Follow Local
Codes
Follow Local
Codes
Chassis
Ground
(CG)
Isolated Bus
DC Ground
See Table 1
for cable size
Wire sized equal
or greater than
maximum power
feed
Building Steel
DIG
If the distance to the AC power source is short (less than a few meters); communication to
the DeltaV controller is through fiber; and there is no galvanic connection to any other
field devices, then the chassis ground and DC ground can be connected together inside
the cabinet. This permits the use of one cable from the junction box (JB) to the next ground
location. For example, if the optically isolated CHARM junction box (JB) is attached to the
steel girder on a drilling rig with the transformers also mounted to the steel directly under
the JB, then weld the ground bar to the steel close to the transformers to establish both a
separately derived safety ground and a JB DC ground. It is also optimal to maintain a length
of less than 100 meters for the shielded signal wires in addition to assuring that signal
wires are not in close proximity to interfering sources.
28
DeltaV power and grounding options
Figure 7-6: High integrity power and grounding for CHARM enclosure
CHARM Enclosure
DC ok
DC ok
AC/DC
Power
Supply
Isolation
Transformer
AC/DC
Power
Supply
PS1
PS1
AC 100-240V
AC 100-240V
N
Communications with
DeltaV Should be
connected via Fiberoptic cable for distance
exceeding 200 ft.
N
L
L
N
AC Feed 1
G
Follow Local
Codes
CB1
CB1
Isolation
Transformer
N
AC Feed 2
G
Follow Local
Codes
Follow Local
Codes
Chassis
Ground
(CG)
Isolated Bus
DC Ground
See Table 1
for cable size
Wire sized equal
or greater than
maximum power
feed
Building Steel
DIG
29
DeltaV power and grounding options
Figure 7-7: Power and grounding for CHARM enclosure with clean power
CHARM Enclosure
DC ok
DC ok
AC/DC
Power
Supply
AC/DC
Power
Supply
PS1
PS2
AC 100-240V
AC 100-240V
N
Communications with
DeltaV Should be
connected via Fiberoptic cable for distance
exceeding 200 ft.
N
L
CB1
L
CB1
Power should be at or better than stated in
EN 61000-3-12
EN 61000-3-11
Electromagnetic compatibility (EMC) – Part 3-12:
Limits for harmonic currents produced
by equipment connected to public lowvoltage systems with input current >16 A
and ≤75 A per phase
Electromagnetic compatibility (EMC) – Part 3-11:
Limitation of voltage changes, voltage
fluctuations and flicker in public lowvoltage supply systems – Equipment
with rated current ≤75 A and subject to
conditional connection
Follow Local
Codes
Chassis
Ground
(CG)
Isolated Bus
Ground connection from Power Source
not necessary if power is controlled
with an Active Harmonic Filter
DC Ground
See Table 1
for cable size
Building Steel
DIG
A separately derived ground is maintained by the use of a DC/DC power converter. The
DC/DC converter also assures criteria A is maintained as stated in IEC 61000-4-11.
Figure 7-8 shows the placement of the DC/DC supplies when the converters are not located
in the CHARM enclosure and Figure 7-9 depicts the typical configuration when the DC/DC
converters are located in the same enclosure as the CHARM system.
30
DeltaV power and grounding options
Figure 7-8: Remote DC solution for CHARM power and grounding
CHARM Enclosure
CB1
Communications with
DeltaV should be
connected via Fiberoptic cable for distance
exceeding 200 ft.
CB1
Up to 100 ft.
Output Nominal
+24VDC 10 A
Output Nominal
+24VDC 10 A
DC/DC
Power
Supply
DC/DC
Power
Supply
PS1
PS1
Input
+18-32VDC 10 A
Input
+18-32VDC 10 A
Follow Local
Codes for
PE Ground
Chassis
Ground
(CG)
Isolated Bus
+24VDC
Nominal
DC Ground
See Table 1
for cable size
Building Steel
DIG
31
DeltaV power and grounding options
Figure 7-9: Localized DC solution for CHARM power and grounding
CHARM Enclosure
Output Nominal
+24VDC 10 A
Output Nominal
+24VDC 10 A
DC/DC
Power
Supply
DC/DC
Power
Supply
PS1
PS1
Input
+18-32VDC 10 A
Input
+18-32VDC 10 A
CB1
Communications with
DeltaV should be
connected via Fiberoptic cable for distance
exceeding 200 ft.
CB1
+24VDC
Nominal
+24VDC
Nominal
Follow Local
Codes for
PE Ground
Isolated Bus
DC Ground
Chassis Ground (CG)
See Table 1 for cable size
Building Steel
DIG
SIS
The M-series SIS products are easily integrated into an S-series system by connecting the
SIS adaptor module either to the right of the S-Series 2-wide carrier, after the S-series
8-wide carrier, or after the S-series left extender. DC power with the highest integrity is
provided as shown in Figure 7-10. Two AC/DC power supplies are combined through a
32
DeltaV power and grounding options
redundancy module to feed the 24 VDC to one group of SLSs or SISNet Repeaters while
two other AC/DC power supplies through another redundancy module provide the DC
power for the SLSs or SISNet Repeaters partners (see Figure 7-11). Whenever possible it is
preferable to run the 24 VDC positive and 24 VDC return together as a twisted pair. When
the power is brought to the SIS panel as in Figure 7-11, both groups of DC returns may be
bused together at the terminal blocks.
33
DeltaV power and grounding options
Power supply configuration
Figure 7-10: Typical SLS power panel with maximum supply redundancy
Primary SLS Power
24V DC
Fuse TB
Fuse TB
Secondary SLS Power
24V DC
Chassis
Ground
Chassis
Ground
Parallel
Parallel
Parallel
Single
Single
Single
Output
Max.
80A
AC/DC
Power
Supply
AC/DC
Power
Supply
Dual
Redundancy
Module
PS1
PS2
DC 24V
960W/1440W
Input 1
DC 24-28V
40A
AC 100240V
Input 2
DC 24-28V
40A
N L
L
C
N
N
O
O
C
M
L
N
G
CB1
CB2
AC/DC
Power
Supply
Dual
Redundancy
Module
PS3
PS4
DC 24V
960W/1440W
AC 100240V
Input 1
DC 24-28V
40A
AC 100240V
Input 2
DC 24-28V
40A
N L
G N
Filter/
Surge
Suppression
Device
Single
DC 24V
960W/1440W
N L
G N
Parallel
Output
Max.
80A
AC/DC
Power
Supply
L
C
N
N
O
O
C
M
L
N
G
Filter/
Surge
Suppression
Device
G N
CB3
DC 24V
960W/1440W
AC 100240V
N L
L
C
N
N
O
O
C
M
L
N
G
Filter/
Surge
Suppression
Device
G N
CB4
L
C
N
N
O
O
C
M
L
N
G
Filter/
Surge
Suppression
Device
Primary
AC Power
Secondary
AC Power
PE
To DIG
Note 1) Use either a combined Suppressor Filter
Module or a Type II or Type III Surge
Suppressor followed by a Filter sized
appropriately
Adjacent Enclosure
Enclosure door
Enclosure PE Ground Lug
6 AWG minimum
34
DeltaV power and grounding options
Note
Connect the 24 VDC return (-) terminal of the power supplies to DeltaV DC ground. This is
accomplished as shown in Figure 7-11 from the bused DC ground wire connected to the DC Ground
bus.
35
DeltaV power and grounding options
Incorporating M-series SLS into S-series
Figure 7-11: SLS highest integrity power and grounding
SLS
Secondary
+24VDC
ROW 1
Size wire
per max.
current
capacity
ROW N
ROW 1
+24VDC
Return
ROW N
+24VDC
Primary
SLS Power
Primary
+24VDC
ROW N
ROW 1
ROW 1
+24VDC
Return
ROW N
ROW 1
SLS 1B
ROW 1
SLS 2B
ROW 1
SLS 3B
ROW 1
SLS 4B
+24VDC
Primary
DeltaV
Power
+24VDC
14
AWG
ROW 1
SLS 1B
ROW 1
SLS 2B
ROW 1
SLS 3B
ROW 1
SLS 4B
32 Logic Solvers Total
ROW N
SLS 1A
ROW N
SLS 1B
ROW N
SLS 2A
ROW N
SLS 2B
ROW N
SLS 3A
ROW N
SLS 3B
ROW N
SLS 4A
ROW N
SLS 4B
ROW N
SIS-NET
1A
ROW N
SIS-NET
1B
Install 120 ohm
terminators on
one-wide carrier
Row N
14 AWG
Chassis Ground (CG)
Isolated Bus
To DIG
36
DC Ground
To DIG
Adjacent Enclosure
6 AWG minimum
Enclosure door
Enclosure PE Ground Lug
DeltaV power and grounding options
Figure 7-12 shows an option for powering a redundant SLS safety system from one pair of
redundant power supplies where the redundancy is provided from two AC/DC power
supplies that are combined through a redundancy module as seen in one group in
Figure 7-10. Ground the SIS power supply return, DeltaV power supply return, and system
power supply return at the DC ground bus.
Figure 7-12: SLS high integrity power and grounding
SLS Power
+24VDC
ROW 1
Size wire
per max.
current
capacity
ROW N
ROW 1
+24VDC
Return
ROW N
+24VDC
DeltaV
Power
+24VDC
14
AWG
32 Logic Solvers Total
Install 120 ohm
terminators on
one-wide carrier
Row N
14 AWG
Chassis Ground (CG)
Isolated Bus
To DIG
DC Ground
To DIG
Adjacent Enclosure
6 AWG minimum
Enclosure door
Enclosure PE Ground Lug
37
DeltaV power and grounding options
Note
The 24 VDC that powers the railbus through the system power supply should be a separate power
source from the 24 VDC power supplying the SIS products if S-series cards and SIS cards are in the
same system. However, if the entire DeltaV system consists of the system power supplies,
controllers, and safety products (Logic Solvers and SISNet Repeaters) then the controller and safety
system power can be supplied from the same power source.
Multiple Distributed Enclosures: Power and
Grounding Schemes
Figure 7-13: Grounding with multiple distributed enclosures
Power Disconnect Panel
Primary UPS
1
Static Bypass
Switch
AC Primary 2
Battery Bank or
Flywheel Storage
LINE
AC Feed 1
AC Primary 1
2
N
GROUND
Inverter
NEUTRAL
Bypass
Transformer
Rectifier
N
AC Primary N
G
Power Disconnect Panel
Secondary UPS
1
Static Bypass
Switch
AC Secondary 2
Battery Bank or
Flywheel Storage
LINE
AC Feed 2
AC Secondary 1
2
N
GROUND
Inverter
NEUTRAL
Bypass
Transformer
Rectifier
N
AC Secondary N
G
Instrument Enclosure 1
L
N
PE
AC
Primary
1
L
N
PE
AC
Secondary
1
Chassis
Ground
(CG)
Enclosure
door
+24VDC
+24VDC
+24VDC
+24VDC
Shield
Bar
Instrument Enclosure 2
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
L
N
PE
AC
Primary
2
L
N
PE
AC
Secondary
2
Chassis
Ground
(CG)
DC
Ground
+24VDC
+24VDC
+24VDC
+24VDC
Shield
Bar
Enclosure
door
Isolated
Bus
Enclosure PE
Ground Lug
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
Building Steel
DIG
L
N
PE
+24VDC
+24VDC
Chassis
Ground
(CG)
Enclosure PE
Ground Lug
Isolated Bus
+24VDC
+24VDC
AC
Secondary
N
Enclosure
door
Isolated
Bus
L
N
PE
AC
Primary
N
DC
Ground
Enclosure PE
Ground Lug
Building Steel
38
Instrument Enclosure N
Shield
Bar
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
DC
Ground
Isolated
Bus
DeltaV power and grounding options
Any DeltaV system (M-series, S-series, or CHARMs) can be configured as shown in
Figure 7-13. The highest integrity system has both UPSs located in the same area as all of
the DeltaV enclosures. An equally high integrity configuration would have one UPS and
one filtered isolation transformer in addition to surge suppressors in all of the enclosures.
The ground bus-bar shown in Figure 7-13 and Figure 7-14 located just prior to the DIG only
requires one conductor leading to the actual earth ground point.
For example, on a multi-story building or platform, as the DeltaV grounds leave the floor,
both the DC ground and chassis ground are connected to a common ground that is either
welded to building steel or bolted using conductive grease on the bonding surfaces to
building steel. The vertical ground run to the actual DeltaV instrument ground only needs
to be a single cable sized as shown in Table 5-1 or Table 5-4. If the total length exceeds 300
feet then the 4/0 cable is adequate. In addition, if the DeltaV equipment is located in a
multistory structure every other floor can be connected together.
Figure 7-14: Close proximity enclosures with chassis and DC grounds together
Power Disconnect Panel
Isolation Transformer
Filter
1
AC Primary 1
2
AC Primary 2
LINE
GROUND
AC Feed 1
NEUTRAL
N
N
AC Primary N
G
Power Disconnect Panel
Secondary UPS
Bypass
Transformer
1
Static Bypass
Switch
AC Secondary 2
Battery Bank or
Flywheel Storage
LINE
AC Feed 2
AC Secondary 1
2
N
GROUND
Inverter
NEUTRAL
Rectifier
N
AC Secondary N
G
Instrument Enclosure 1
L
N
PE
AC
Primary
1
L
N
PE
AC
Secondary
1
Chassis
Ground
(CG)
Enclosure
door
Enclosure PE
Ground Lug
+24VDC
+24VDC
+24VDC
+24VDC
Shield
Bar
Instrument Enclosure 2
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
L
N
PE
AC
Primary
2
L
N
PE
AC
Secondary
2
Chassis
Ground
(CG)
DC
Ground
Isolated
Bus
6 AWG minimum
+24VDC
+24VDC
+24VDC
+24VDC
Shield
Bar
Enclosure
door
Enclosure PE
Ground Lug
Instrument Enclosure N
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
6 AWG minimum
+24VDC
+24VDC
L
N
PE
+24VDC
+24VDC
AC
Secondary
N
Chassis
Ground
(CG)
DC
Ground
Isolated
Bus
L
N
PE
AC
Primary
N
Enclosure
door
Enclosure PE
Ground Lug
Shield
Bar
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
DC
Ground
Isolated
Bus
6 AWG minimum
Building Steel
DIG
39
DeltaV power and grounding options
If the I/O count is relatively small (less than 100 I/O points) or the cost benefit evaluation
results in the system not requiring the highest integrity, then the chassis ground may be
connected as shown in Figure 7-14.
Figure 7-15: Enclosure grounding with adjacent bays
Power Disconnect Panel
Primary UPS
AC Primary 1
2
AC Primary 2
N
Battery Bank or
Flywheel Storage
LINE
AC Feed 1
1
GROUND
Inverter
NEUTRAL
Static Bypass
Switch
Bypass
Transformer
Rectifier
N
AC Primary N
G
Power Disconnect Panel
Secondary UPS
AC Secondary 1
2
AC Secondary 2
N
Battery Bank or
Flywheel Storage
LINE
AC Feed 2
1
GROUND
Inverter
NEUTRAL
Static Bypass
Switch
Bypass
Transformer
Rectifier
N
AC Secondary N
G
Enclosure 1 Bay 1
L
N
PE
+24VDC
+24VDC
AC
Primary
1
L
N
PE
+24VDC
+24VDC
AC
Secondary
1
Chassis
Ground
(CG)
Enclosure
door
Enclosure PE
Ground Lug
Shield
Bar
Isolated
Bus
Enclosure 1 Bay 2
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
L
N
PE
+24VDC
+24VDC
AC
Primary
2
L
N
PE
+24VDC
+24VDC
AC
Secondary
2
Chassis
Ground
(CG)
DC
Ground
Enclosure
door
Shield
Bar
Enclosure 1 Bay N
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
L
N
PE
+24VDC
+24VDC
L
N
PE
+24VDC
+24VDC
AC
Primary
N
AC
Secondary
N
Chassis
Ground
(CG)
DC
Ground
Enclosure
door
Isolated
Bus
Enclosure PE
Ground Lug
Shield
Bar
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
DC
Ground
Isolated
Bus
Enclosure PE
Ground Lug
Enclosire 2
Enclosure 3
Building Steel
Isolated Bus
Building Steel
DIG
When multiple enclosures are physically connected together and the highest ground
integrity is desired as shown in Figure 7-15, then the chassis reference buses may be
interconnected to each other. The DC ground buses are also interconnected. This method
can be used for up to four adjacent bays. It is best to use a center bay for the
interconnection between the enclosure structure and the external ground bus.
40
DeltaV power and grounding options
Figure 7-16 and Figure 7-17 show examples where multi-paired cables are brought to a
DeltaV cabinet in a type of homerun cable with either conductive armor or metal
jacketing.
CAUTION!
The overall conductive surface of metallic or armored cable must always be connected to the
safety ground system in a DeltaV enclosure. Follow local codes and regulations.
Figure 7-16: Highest integrity cable shielding solution
Instrument Enclosure
L
N
PE
+24VDC
+24VDC
L
N
PE
+24VDC
+24VDC
AC
Primary
1
AC
Secondary
1
Chassis
Ground
(CG)
ARMORED/METAL shielding
Armored and screened
instrument cables from the field
Enclosure
door
DeltaV
Shield
Bar
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
DC
Ground
Isolated
Bus
Enclosure PE
Ground Lug
Grounds from
other Enclosures
Building Steel
Isolated Bus
Ground from
Separately
Derived AC
source
Building Steel
DIG
Figure 7-16 shows the overall armored or metal jacket connected to the DeltaV chassis
ground bar, which is in turn connected to building steel and protective earth. The
individual cable shields inside the armored bundle are typically connected to the DeltaV
shield bar, which is also connected to the chassis ground reference.
41
DeltaV power and grounding options
Figure 7-17: Localized systems on welded metal structure with minimal external influences
Instrument Enclosure
L
N
PE
+24VDC
+24VDC
L
N
PE
+24VDC
+24VDC
AC
Primary
1
AC
Secondary
1
Chassis
Ground
(CG)
ARMORED/METAL shielding
Armored and screened
instrument cables from the field
Enclosure
door
DeltaV
Shield
Bar
DeltaV
Primary
Power
+24VDC
DeltaV
Secondary
Power
+24VDC
DC
Ground
Isolated
Bus
Enclosure PE
Ground Lug
6 AWG minimum
Ground from
Separately
Derived AC
source
Grounds from
other Enclosures
Welded to
Building Steel
Isolated Bus
2 AWG
Figure 7-17 represents a special case where an entire structure is considered to be at an
equipotential. One example is a floating platform. Other reasons for connecting the
shields as shown in Figure 7-17 are as follows:
•
This maintains the separately derived AC power sources in close proximity to the
enclosures (within 100 meters)
•
The individual signal shield should not be in areas of high noise susceptibility, that is,
not in close proximity to VFDs or in any lightning zone 0 or zone 1 without signal
surge protection.
•
The maximum distance from any enclosure to its corresponding external ground bar
should be 100 feet.
Use Table 5-4 to determine the ground conductor sizing.
Floating AC and high-resistance ground
Removing the connection of AC ground to the dedicated DeltaV instrument ground also
changes the way in which the AC power distribution system must be grounded. The AC
power and grounding system can be designed with floating or high-resistive grounds
(HRG), in accordance with applicable electrical codes. The DeltaV DC power must remain
solidly grounded. The controller and I/O components are certified based on the prescribed
grounding of the equipment.
Important
DeltaV AC discrete I/O products are tested and certified for use with solidly grounded AC systems
and should not be used on a floating or high-resistive ground. However, isolated AC channels are
permitted.
42
DeltaV power and grounding options
The Emerson bulk power supplies are capable of providing up to 1500 VDC of isolation
from the AC power source, and they must be installed per the manufacturer's instructions.
AC power and grounding is governed by the applicable codes and regulations and is
independent of the DeltaV DC power requirements.
Note
If an HRG or a floating AC power is used to power a DeltaV bulk power supply, a Surge Suppression
Device (SPD) with filters is recommended immediately prior to the bulk power supply.
Important
A re-strike transient is produced in many HRG systems which introduces a transient. This re-strike
transient is generated from the system when a ground fault occurs in an attempt to isolate the leg
with the fault. Use adequate filtering to preclude detrimental affects to DeltaV systems.
43
DeltaV power and grounding options
44
Grounding topologies
8
Grounding topologies
Topics covered in this chapter:
•
•
•
Star or single-point ground
Mesh star ground network
Hybrid star mesh ground network
Equipotential ground: Every location within the grounding network is at the same
potential voltage. This is the ideal solution for any grounded system. There are many
grounding methods which work very well to achieve this goal. IEC 60364-4-44 Low-voltage
electrical installations - Part 4-44: Protection for safety - Protection against voltage disturbances
and electromagnetic disturbances is an excellent source for grounding topologies. When
connecting ground cables excessive service loops should be avoided. The ground cables
should be in as direct a path as possible. When crossing power lines, the separation should
be as great as possible and at right angles to the power cables.
Star or single-point ground
DeltaV functions extremely well using a Star Grounding topology as shown in Figure 8-1.
45
Grounding topologies
Figure 8-1: Single-point star grounding system
Welded to
building steel
DIG
Mesh star ground network
Many control systems today are preassembled in structures with raised floors. This type of
installation facilitates a mesh star ground system as shown in Figure 8-2. When connecting
the DeltaV chassis ground to the mesh, the ground cable or ground straps should be as
46
Grounding topologies
short as possible. Mesh squares must be no less than two meters per side(1). All mesh
crossings should be exothermically welded or tightly bolted, maintaining corrosion free
joints with a typical Joint resistance of 500 µ Ω(2).
Figure 8-2: Mesh star ground network
Isolation Transformer
Bypass
Transformer
Rectifier
Inverter
N
Static Bypass
Switch
Filter
Secondary UPS
N
Battery Bank or
Flywheel Storage
G
G
Welded to
Building
Steel
DIG
Welded to
Building
Steel
(1) IEC 60364-4-44, Low-voltage Electrical Installations Part 4-44: Protection for safety - Protection against voltage disturbances and
electromagnetic disturbances, Ed. 2.0, 2007
(2) IEEE Standard 1100-2005, Recommended Practice for Power and Grounding Electronic Equipment (Emerald Book)
47
Grounding topologies
Hybrid star mesh ground network
Figure 8-3: Hybrid star mesh ground network
Isolation Transformer
Rectifier
Inverter
N
Static Bypass
Switch
Filter
Secondary UPS
Bypass
Transformer
N
Battery Bank or
Flywheel Storage
G
Welded to
Building
Steel
DIG
48
Welded to
Building
Steel
G
Interference and transients
Appendix A
Interference and transients
Topics covered in this appendix:
•
•
•
Static (capacitive) coupling
Voltage differentials
Inductive coupling
Static (capacitive) coupling
Static coupled interference is the result of noise coupling to instrumentation and the
signal's shield being in close proximity to the noise source. The following figure is a
simplified illustration of two return paths on which capacitive coupled interference travels.
The dashed return path through DeltaV represents the path noise takes when the shields
are tied to the isolated instrument ground. The noise returns to the location where the
chassis ground and DC ground is first connected to building steel. At that point a parallel
path is established. Some current will travel through building steel with the remainder
following the copper to steel, then to its source.
•
Noise wants to return to its source following the path of least resistance.
•
Steel is 10 times more resistive than copper
•
However, due to the skin effect and the multiple paths in the steel, the path through
steel is 4.5 time less resistive overall than the copper path.
Interference that is caused by static coupling is common in industrial applications. It
occurs from noise originating from the commutation of motors; the rapid switching of
SCRs and IGBTs when variable frequency drives recreate sine waves to control motor
speed; and tooling such as welders.
By connecting the shields to building steel, noise returns to its source more efficiently.
49
Interference and transients
Figure A-1: Static coupled interference return paths from motor noise
KEY
Return path thru DeltaV
Return path thru Steel
Chassis Ground
Capacitive
Coupled Noise
to signal shield
Steel Floor
Noise
Elevation
at Motor
Plant
Ground
Grid
DeltaV Instrument
Ground Bonding
Point
Voltage differentials
Voltage differentials occur as a result of many events common to industry, such as
lightning, utility failures, and equipment failures. For example, if lightning strikes on one
side of a structure and DeltaV signal wires travel into the area near the lightning stroke,
then static coupling can be induced on signal shields even if the associated DeltaV
enclosure is in a different part of the structure. Figure A-2 represents a fault at time equals
zero that establishes a voltage differential in a facility.
50
Interference and transients
Figure A-2: Static coupled from Voltage Differential fault
KEY
Return path thru DeltaV
Return path thru Steel
Chassis Ground
Instrument
Enclosure
Signal Wire Shield
Steel
Structure
Voltage Differential from
1) Utility Fault
2) Equipment Fault
3) Lightning
Noise
Elevation
from Fault
Building Steel
Bonding Points
Plant
Ground
Grid
DeltaV Instrument
Ground Bonding
Point
Typically, voltage differential faults that result from equipment failure, utility faults, or
lightning create a transient signal which subsides with a type a diminishing ring similar to
the gate function (sin(x)/x). However, the decay more closely resembles a zero order
Bessel function. Since noise attempts to return to its source, the actual elevation in
impulse voltage at one area establishes a differential with respect to more remote
locations. Multiple paths through steel and copper grounds eventually equalize due to the
heating (I2 •R) losses throughout the numerous return eddy paths.
Inductive coupling
When signal wires are in close proximity to high current conductors, such as the down
conductor on a lightning system, lightning strikes induce a current on its air terminal and
possibly the signal conductors too. A voltage differential is established on the wire and
ground system which dissipates through numerous eddy current paths as the induced
interference attempts to return to its source. The most direct path is the one in which the
shield is connected to building steel as close as possible.
Industry example: A 55 KV precipitator used to covert ash into small pellets that can be
collected was located at the top of a multistory chimney. The ground conductor was an
exposed copper wire traversing the length of the chimney into the ground grid. This
ground cable was also connected to building steel on every floor. A signal cable was run in
parallel to the precipitator's ground wire, which caused a 90 VPP transient to be coupled
onto the signal during the precipitation process. This coupling process was due to
inductive coupling as shown in Figure A-3.
51
Interference and transients
Figure A-3: Inductive coupling from down-conductor into signal cable
KEY
Return path thru DeltaV
Return path thru Steel
Chassis Ground
Precipitator
Ground
Cable from
Precipitator
Bonding
Points to
Building Steel
Inductive
Coupled
Interference
Instrument
Enclosure
Signal Cable
Temperature Signal
DeltaV DIG
52
High integrity ground systems
Appendix B
High integrity ground systems
Highest integrity systems have shields
connected to chassis ground
Perform a cost/benefit evaluation when choosing the proper location to land the shield
drain wires. There is a definite cost savings associated with connecting both the DC ground
and the Chassis Ground (CG) together. This requires only one functional ground
connection to the DeltaV Instrumentation Ground (DIG). If however, the highest integrity
ground system yielding the least amount of disruptive events is required, then the shields
should be connected to the CG for the following reasons:
•
Noise wants to return to its source following the path of least resistance (refer to See
Appendix A)
•
Scientific evidence confirms that noise on shields connected to DC ground adversely
influences system integrity. The Pin one problem first recognized by Neil Muncy and
documented in his 1994 Audio Engineering Society paper has been confirmed in
multiple studies. Although this issue has been of particular concern to audio
engineers, the conclusion applies to all engineering disciplines including control
systems.
•
Various standards recommend that shields be connected to enclosure or chassis
ground:
-
PROFIBUS recommends connecting shield drains to case ground. Connecting
shields to chassis ground provides equalization; mitigates interference currents;
ensures compliance with EMC regulations; and should be installed with regard to
the requirements of high frequency currents. Profibus Technical Description Sept.
1999.
-
ANSI/ISA-RP12.06.01-2003 Recommended Practice for Wiring Methods for
Hazardous (Classified) Locations Instrumentation Part 1: Intrinsic Safety requires
that shields be connected to equipment or chassis ground.
Equipment manufacturers are continually designing products to be smaller, with less
weight, and at an increased savings. This has led to products operating at higher
frequencies resulting in electrical components, such as indictors and transformers, being
much smaller. Emerson has been and will remain a leader in providing a power and
grounding solutions for controlling equipment designed for today's adverse environments
as well as unforeseen future applications.
53
High integrity ground systems
54
Checklists for verifying site ground
Appendix C
Checklists for verifying site ground
Topics covered in this appendix:
•
•
Site ground verification checklists
Checklists
Site ground verification checklists
Equipment
•
Power line analyzer such as a Fluke 434 or equivalent
•
Clamp-on RMS ammeter (for AC and DC current measurements)
•
Recording thermometer/humidity meter
•
Fluke 199 or 200 MHz digital oscilloscope (for earth/noise verification)
•
Calibrated 4-1/2 digit DVM with accuracy of ± 0.05%, or better.
•
Fluke 123 - 20 MHz digital scope meter (for fieldbus capacitance verification)
•
Fluke DSP-2000 cable tester for certification of CAT5 and fiber optic cabling
•
Fluke 1625 Earth Ground Tester (or equivalent)
•
Fluke 1630 Earth Ground Clamp Meter
Note
Equivalent equipment may be substituted for the equipment listed above.
Product information
Review the most current revision of product manuals and installation manuals prior to
checkout.
Checklists
55
Checklists for verifying site ground
Good engineering practices for general systems
Table C-1: Good engineering practices for general systems
Good engineering practices for general systems
Page __ of __
Verification
Answer
If No please comment
Are servers, stations, routers, and so on,
cleaned up (software) and reinstalled according to station specific installation instructions?
Yes / No / N.A.
By: ________________
Are the proper procedures and equipment
used for assembling and connecting wiring, connectors and terminations (power,
alarming, I/O, Busses, network, and so
on)?
Yes / No / N.A.
Does a spot check of the assembly procedures used (for example, crimping of terminations, and so on) indicate that proper
materials, tools and procedures were
used?
Yes / No / N.A.
Is redundancy (controller, I/O, power, network, and so on) properly identified and
tested?
Yes / No / N.A.
By: ________________
Date: __________
By: ________________
Date: __________
By: ________________
Date: __________
Are connections which have to be made
Yes / No / N.A.
during site installation (for example, power and grounding) clearly tagged and identified?
By: ________________
Are system diagnostics performed and do Yes / No / N.A.
the diagnostics readings result in expected
values?
By: ________________
Comments:
56
Date: __________
Date: __________
Date: __________
Checklists for verifying site ground
Environmental conditions
Table C-2: Environmental conditions
Environmental conditions
Page __ of __
Verification
Answer
If No please comment
Is the environment to which the system
parts are exposed, (temperature, humidity, vibration) as per design specifications
in normal operation? If the site is still under construction will these cause adverse
effects?
Yes / No / N.A.
By: ________________
Date: __________
Are system components free of contamiYes / No / N.A.
nation due to the installation (for example,
drill shavings, cement dust, and so on)?
Visually inspect the top of the DeltaV cards
and verify that there is no sign of contamination, especially by copper or other conducting material.
By: ________________
Is the installation and surrounding area
free of dirt and dust and properly protected against contamination from such?
By: ________________
Yes / No / N.A.
Date: __________
Date: __________
Verify that there is a proper environmental Yes / No / N.A.
system to keep the DeltaV system from
reaching its maximum or minimum operation temperature.
By: ________________
Verify that there is no corrosive buildup on Yes / No / N.A.
any component of the DCS system. This includes bulk power supplies, the DeltaV
system, the I/O cards and the grounding
system.
By: ________________
Date: __________
Date: __________
Comments:
57
Checklists for verifying site ground
Power and grounding connections
Table C-3: Power and grounding connections
Power and grounding connections
58
Page __ of __
Verification
Answer
If No please comment
Are the connections performed per design, properly terminated, and labeled
(proper size for distance)?
Yes / No / N.A.
By: ________________
Are the cable sizes and type in accordance
with the intended use? (insulated vs. uninsulated, solid wire vs. small diameter
multi strands, and so on)
Yes / No / N.A.
Are the cable runs made according to this
manual and do they conform to pertinent
safety regulations?
Yes / No / N.A.
Date: __________
By: ________________
Date: __________
By: ________________
Date: __________
Are the lengths of all power and grounding Yes / No / N.A.
cables from the dedicated instrumentation points (power source and dedicated
plant ground connection) to the system
within the guidelines of this manual?
By: ________________
Is the Dedicated Instrumentation Ground Yes / No / N.A.
(DIG) connected to the lowest available
dedicated connection to true earth and is
this connection's resistance verified using
one of the methods as described in the Site
Preparation and Design for DeltaV Digital Automation Systems manual ?
By: ________________
Is the DIG connection to true earth also
connected to the plant power grid system
as detailed in this manual?
By: ________________
Yes / No / N.A.
Date: __________
Date: __________
Date: __________
Are the Separately Derived Sources using a Yes / No / N.A.
neutral to ground bond at the source that
is connected to the DeltaV Instrument
Ground?
By: ________________
Are the applied Separately Derived Sources using proper redundancy and UPS's, as
intended by the customer?
By: ________________
Yes / No / N.A.
Date: __________
Date: __________
Are all applicable power connections and
Yes / No / N.A.
distributions installed, inspected, tagged
and verified for conformity to local and national codes applicable to the end user (for
example, NEC, CSA, IEEE, CE, NEN, etc.)?
By: ________________
If the DIG is connected to the Plant Ground Yes / No / N.A.
Grid (PGG) then was the PGG engineered
properly?
By: ________________
Date: __________
Date: __________
Checklists for verifying site ground
Table C-3: Power and grounding connections (continued)
Power and grounding connections
Verification
Page __ of __
Answer
If the DIG is connected to the Plant Ground Yes / No / N.A.
Grid (PGG) then if possible verify the integrity of the PGG. Is if of high integrity and
free of corrosion?
If No please comment
By: ________________
Date: __________
Comments:
59
Checklists for verifying site ground
Power and grounding connections with triad
Table C-4: Power and grounding connections with triad
Power and grounding connections with triad
Page __ of __
Use this document if the DIG is connected to a TRIAD, or a series of three grounding rods bonded together.
The next three rows assume that it is safe to check the earthing system and that each point of
the triad can be isolated and tested.
Verification
Answer
Check the DeltaV grounding resistance of Yes / No / N.A.
ground rod #1 using a three-point grounding test procedure.
If No please comment
By: ________________
Date: __________
(Make sure to calculate the testing impedance from the initial results. The value
should optimally be 1 Ohm or less with a
maximum of 3 Ohms.)
Check the DeltaV grounding resistance of Yes / No / N.A.
ground rod #2 using a three-point grounding test procedure.
By: ________________
Date: __________
(Make sure to calculate the testing impedance from the initial results. The optimal
value should be 1 Ohm or less with a maximum of 3 Ohms.)
Check the DeltaV grounding resistance of Yes / No / N.A.
ground rod #3 using a three-point grounding test procedure.
(Make sure to calculate the testing impedance from the initial results. The value
should optimally be 1 Ohm or less with a
maximum of 3 Ohms.)
Comments:
60
By: ________________
Date: __________
Checklists for verifying site ground
General field device installation
Table C-5: General field device installation
General field device installation
Page __ of __
Complete this worksheet page for each device sampled. Emerson recommends a minimum of
10% of the devices and checking at least one of each type of device used.
Verification
Answer
If No please comment
Are devices installed according to good
engineering practices?
• Are they properly mounted?
• Is the orientation correct?
• Are they reachable?
• Are they serviceable?
• Are they properly tagged?
Yes / No / N.A.
By: ________________
Are devices connected according to good
engineering practices? For example:
• Is the case properly grounded? (not to
the shield of the communication cable)
• Are shipping plugs removed and are
unused cable entries properly closed?
• Are drip loops present and effective?
• Are cable conduits properly mounted
and sealed to prevent the entry of
moisture? Are cable runs such that no
sharp metal edges can cut through cable insulation?
• Are cables properly tied so no strain is
present on the terminations?
• Are cables routed and protected in a
way that will minimize EMI?
• Are unused conductors and shields
properly terminated, with a minimal
loss of the overall wire protection?
• Is the shield of the cable tied back and
insulated so that it cannot make contact with the case of the device?
Yes / No / N.A.
Are cable trays to the device properly
grounded?
Yes / No / N.A.
Date: __________
(minimim 10% spot-check recommended)
By: ________________
Date: __________
(minimim 10% spot-check recommended)
By: ________________
Date: __________
(minimim 10% spot-check recommended)
61
Checklists for verifying site ground
Table C-5: General field device installation (continued)
General field device installation
Page __ of __
Complete this worksheet page for each device sampled. Emerson recommends a minimum of
10% of the devices and checking at least one of each type of device used.
Verification
Answer
Are cable trays at least 18" from any power Yes / No / N.A.
source or cable tray that carries power?
Note
No instrumentation cables connected to
devices should be in a cable tray with power cables, or VAC control cables.
Comments:
62
If No please comment
By: ________________
Date: __________
(minimim 10% spot-check recommended)
Checklists for verifying site ground
I/O wiring (conventional, HART, serial, and bus types)
Table C-6: I/O wiring (conventional, HART, serial, and bus types)
I/O wiring (conventional, HART, serial, and bus types)
Page __ of __
Verification
Answer
If No please comment
If there are serial connections to other devices (for example, PLC, weigh scale, and
so on), are they using the same dedicated
ground system or if not, are the communication connections isolated?
Yes / No / N.A.
By: ________________
Are cable shields properly terminated at
the shield bar and connected to ground at
the power source's end only (Remove and
measure with DVM)?
Yes / No / N.A.
Is cable armor terminated and connected
to ground according to the guidelines in
the document Site Preparation and Design
for DeltaV Digital Automation Systems?
Yes / No / N.A.
Date: __________
By: ________________
Date: __________
(minimum 10% spot check recommended)
By: ________________
Date: __________
(minimum 10% spot check recommended)
Is all I/O wiring termination and connecYes / No / N.A.
tion performed according to Good Engineering Practices? For example:
• Stripped back in such a manner that
signals cannot short to other terminals?
• Heat-shrink on cut back cables?
• Correctly terminated, labeled and color-coded?
• Are cable runs such that no sharp metal edges can cut through cable insulation?
• Are cables properly tied so no strain is
present on the terminations?
• Are cables routed in a way that EMI interference will be at a minimum?
• Are unused conductors and shields
properly terminated to ground on one
end only?
• Proper crimp sizes of terminations
used for cables?
• Proper termination for the application?
• Special terminations when 2 wires in 1
crimp are used?
By: ________________
Are millivolt and pulse count signals connected through individually shielded twisted pair cables?
By: ________________
Yes / No / N.A.
Date: __________
(minimum 10% spot check recommended)
Date: __________
(minimum 10% spot check recommended)
63
Checklists for verifying site ground
Table C-6: I/O wiring (conventional, HART, serial, and bus types) (continued)
I/O wiring (conventional, HART, serial, and bus types)
Page __ of __
Verification
If No please comment
Answer
For Bus systems, do the connections,
Yes / No / N.A.
grounding principles, components and layout conform to applicable BUS standard?
For example:
• Foundation Fieldbus
• ASI bus
• ProfiBus
64
By: ________________
Date: __________
(minimum 10% spot check recommended)
Checklists for verifying site ground
Enclosures
Table C-7: Enclosures
Enclosures
Page __ of __
Complete this worksheet page for each enclosure
Verification
Answer
If No please comment
Is the enclosure free of any
signs of environmental damage?
Yes / No / N.A.
By: ________________
Date: __________
(Corrosion, rust, paint burns,
paint flakes, and so on.)
Is the temperature within the
Yes / No / N.A.
cabinets and enclosures within
the limits specified in the design (measure at least one typical or worst-case application if
necessary)? (Note any devices
in the cabinet creating possible
excessive heat.)
By: ________________
Is the Humidity within the cabi- Yes / No / N.A.
nets and enclosures within the
limits specified in the design
(measure at least one typical or
worst-case application if necessary)?
By: ________________
Are all cable entries in and out
of the cabinets and enclosures
sealed?
Yes / No / N.A.
By: ________________
Are all enclosures properly
positioned and mounted with
groups of enclosures properly
bolted together?
Yes / No / N.A.
Date: __________
Date: __________
Date: __________
By: ________________
Date: __________
Are all tagged and identified
Yes / No / N.A.
connections (power, grounding, communications, and so
on) installed properly? Do they
follow good engineering practices with regard to interconnection?
By: ________________
Are all connections solid and
Yes / No / N.A.
tightened? Is there good conduction in all connections (that
is, no corrosion or hanging wire
strands)?
By: ________________
Date: __________
Date: __________
65
Checklists for verifying site ground
Table C-7: Enclosures (continued)
Enclosures
Page __ of __
Complete this worksheet page for each enclosure
Verification
Answer
If No please comment
Are added metal mounting
parts, doors, and so on, that
can become live during fault
conditions, properly grounded
(for example, properly sized
bonding wires or braids to
ground bus)?
Yes / No / N.A.
By: ________________
Date: __________
Are added metal mounting
Yes / No / N.A.
parts properly protected
against the possibility of their
causing short circuits (for example, when doors are closed)?
By: ________________
Is added equipment properly
mounted for the intentioned
application (vibration, shipping, maintenance, safety, and
so on)?
Yes / No / N.A.
By: ________________
Visually check the grounds in
the enclosure. Does the
grounding follow this manual's
recommendations?
Yes / No / N.A.
Check the impedance and current flow for the enclosure
grounding system
Yes / No / N.A.
Calculate the DeltaV carrier
power implementation. Verify
that it does not exceed the recommendations.
Yes / No / N.A.
Do the network components
used and the network installation follow the design?
Yes / No / N.A.
Date: __________
By: ________________
Date: __________
Results:
By: _____________
__________ Ohms
Date: __________
__________ mA
By: ________________
Date: __________
Are all added cables certified
Yes / No / N.A.
for the application (for example
CAT5 and fiber optic), properly
terminated, labeled and colorcoded?
66
Date: __________
By: ________________
Date: __________
By: ________________
Date: __________
Checklists for verifying site ground
Table C-7: Enclosures (continued)
Enclosures
Page __ of __
Complete this worksheet page for each enclosure
Verification
Answer
If No please comment
Are network cables routed and
installed according to the
guidelines in this manual? Verify that the network cables are
shielded according to the recommendations in this manual.
Yes / No / N.A.
By: ________________
Date: __________
67
Checklists for verifying site ground
AC power system and distribution
Table C-8: AC power system and distribution
AC power system and distribution
Page __ of __
Complete this worksheet page for each enclosure
Enclosure Location:
Breaker Location:
Verify that all AC powered devices are switched off or disconnected.
Recorded Value
Complete
---
With AC power system disconnected, measure impedance of sys- --tem from all line and neutral connections to ground.
(Impedance must be high)
If the impedance is in conformance, have a person approved by
the customer switch on the AC power system. Record the person's name.
Primary AC voltage is within specifications.
(85 to 264 VAC / 47 to 63 Hz measured between line and neutral)
Check the noise level of the AC power.
(Look for noise spikes and excessive noise levels injected into the
AC power)
Ground to neutral voltage is within specification.
(0.00 V ±1.00 VAC)
Secondary AC voltage is within specifications.
(85 to 264 VAC / 47 to 63 Hz Measured between Line and Neutral)
Ground to neutral voltage is within specification.
(0.00 V ±1.00 VAC)
If conforming, it is appropriate to switch ON or reconnect all AC
powered devices.
---
Verify that all AC powered fans, cooling devices, lights, and so on
are running and operational. Using an oscilloscope verify that
they are not creating excessive noise.
---
Verify if LED's of all AC powered devices indicate normal.
---
Comments:
68
---
Checklists for verifying site ground
DC power system and distribution
Table C-9: DC power system and distribution
DC power system and distribution
Page __ of __
Complete this worksheet page for each enclosure
Enclosure Location:
Breaker Location:
Recorded Value
Complete
Verify that all AC-powered devices are switched off or disconnected
With the DC power system disconnected, measure impedance of
system from all line and neutral connections to ground
(Impedance MUST be High)
Apply DC voltage to the distribution system
Primary 24 VDC is within specifications.
(21.6 VDC to 26.4 VDC)
Secondary 24 VDC is within specifications.
(21.6 VDC to 26.4 VDC)
Measure the AC noise level of the 24 VDC power to AC ground at
a resolution of 5 ms/div on the Scope.
(Make sure the scope filtering is off, 1 VAC maximum, and AC
coupled)
Measure the AC noise level of the 24 VDC power to AC ground at
a resolution of 200 ms/div on the scope.
(Make sure the scope filtering is off, 1 VAC maximum and AC
coupled)
Primary 12 VDC is within specifications.
(11.4 VDC to 12.6 VDC)
Secondary 12 VDC is within specifications.
(11.4 VDC to 12.6 VDC)
Measure the AC noise level of the 12 VDC power to AC ground at
a resolution of 5 ms/div on the scope. This should be done at the
DeltaV Controllers.
(Make sure the scope filtering is off, 1 VAC maximum and AC
coupled)
Measure the AC noise level of the 12 VDC power to AC Ground at
a resolution of 200 ms/div on the scope. This should be done at
the DeltaV Controllers.
(Make sure the scope filtering is off, 1 VAC maximum and AC
coupled)
Verify that all DC powered fans, cooling devices, lights, and so on
are running and operational. Using an oscilloscope verify that
they are not creating excessive noise.
69
Checklists for verifying site ground
Table C-9: DC power system and distribution (continued)
DC power system and distribution
Page __ of __
Complete this worksheet page for each enclosure
Enclosure Location:
Breaker Location:
Verify that LEDs of all DC powered devices indicate normal
Comments:
70
Recorded Value
Complete
Checklists for verifying site ground
DeltaV controllers
Table C-10: DeltaV controllers
DeltaV controllers
Page __ of __
Complete this worksheet page for each controller
Enclosure location:
Controller
name:
Value/Comment
Complete
Are the network components used and the network installation as per design?
Yes / No / N.A.
By: ______________
Are all added cables certified for the application (for example CAT5 and fiber optic), properly terminated, labeled and color-coded?
Yes / No / N.A.
Are network cables routed and installed according to
the guidelines in the document Site Preparation and Design for DeltaV Digital Automation Systems?
Yes / No / N.A.
Assembly:
• Back planes plugged in tightly
• All power supplies controllers, I/O modules screwed
in securely (Do not over torque)
• Input power wiring termination tight and labeled
• Network cables locked in place
• Environmental conditions within specifications
System power supply LEDs normal
(Power-ON, Error-OFF)
Active controller's LEDs normal
(Power - ON, Error - OFF if downloaded / Flash if un-configured, Active - ON, Standby - OFF, CN1 - Flash if communicating on the primary control network, CN2 - Flash
if communicating on the secondary control network)
Standby controller's LEDs normal
(Power - ON, Error - OFF if downloaded / Flash if un-configured, Active - OFF, Standby - ON, CN1 - Flash if communicating on the primary control network, CN2 - Flash
if communicating on the secondary control network)
Controller accessible through standard diagnostics
(accessible, primary & secondary communication without increasing errors)
All I/O cards accessible through standard diagnostics
(accessible, no mismatches, no missing cards)
Date: __________
By: ______________
Date: __________
By: ______________
Date: __________
71
Checklists for verifying site ground
Table C-10: DeltaV controllers (continued)
DeltaV controllers
Page __ of __
Complete this worksheet page for each controller
Enclosure location:
Comments:
72
Controller
name:
Value/Comment
Complete
Checklists for verifying site ground
List of equipment used
Table C-11: List of equipment used
List of equipment used
Manufacturer
Type:
Page __ of __
Serial number:
Re-calibration
date:
Used in section
Comments:
73
Checklists for verifying site ground
74
References
Appendix D
References
General reference
Joffe, Elya B. and Lock, Kai-Sang, Grounds for Grounding: A Circuit-to-System Handbook, IEEE
Wiley & Sons, 2010.
Ott, Henry, Electromagnetic Compatibility Engineering, Wiley & Sons, 2009.
Vijayaraghavan, G., Brown, Mark, and Barnes, Malcolm, Practical Grounding, Bounding,
Shielding and Surge Protection, Elsevier, 2004.
Power transmission reference
Electrical Transmission and Distribution Reference Book, Westinghouse, 1950.
Reference books for personnel and property safety
Soares Book on Grounding and Bonding, 10th Edition, International Association of Electrical
Inspectors, 2008.
National Electric Code (NEC) 2011 Handbook, NFPA 70, 2011.
BS 7671:2008 Requirements for Electrical Installations 17th Edition, IET Wiring Regulations,
2008.
Cook, Paul, Commentary on IET Wiring Regulations 17th Edition BS 7671:2008 Requirements
for Electrical Installations, Institute of Engineering and Technology, 2008.
American standards
ANSI/ISA-RP12.06.01-2003, Recommended Practice for Wiring Methods for Hazardous
(Classified) Locations Instrumentation Part 1: Intrinsic Safety.
ANSI/ISA-TR12.06.01-1999, Electrical Equipment in a Class 1, Division 2/Zone 2 Hazardous
Location .
ANSI/ISA-84.01-2004, Application of Safety Instrumented Systems for the Process
Industries.
ANSI-J-STD-607-A-2002, Commercial Building Grounding (Earthing) and Bonding
Requirements for Telecommunications.
ATIS-0600333.2007, Grounding and Bonding of Telecommunications Equipment.
NFPA 780, Standard for the Installation of Lightning Protection Systems.
IEEE standards
IEEE Standard 1100-2005, Recommended Practice for Power and Grounding Electronic
Equipment (Emerald book).
75
References
IEEE Standard 142-2007, Recommended Practices for Grounding of Industrial and
Commercial Power Systems (Green book).
IEEE Standard 493-2007, Recommended Practice for the Design of Reliable Industrial and
Commercial Power Systems (Gold book).
IEEE Standard 1159-1995(R2001), Recommended Practice for Monitoring Electric Power
Quality.
IEEE Standard 519-1992, Recommended Practice and Requirements for Harmonic Control
in Electrical Power Systems.
IEEE Standard 1050 2004, Guide for Instrumentation and Control Equipment Grounding in
Generating Stations.
IEEE Standard 81-1983, Guide for Measuring Earth Resistivity, Ground Impedance, and
Earth Surface Potentials of a Ground System.
IEEE Standard 45-2002, Recommended Practice for Electrical Installation on Shipboard.
IEEE 518-1982(1), Guide for the Installation of Electrical Equipment to Minimize Noise
Inputs to Controllers from External Sources, (not currently supported by IEEE).
US Military Handbook
MIL-HDBK-419A, Grounding, Bonding, and Shielding for Electronic Equipments and
Facilities (Vol. 1 Basic Theory; Vol. 2 Applications), 1987.
European international standards
IEC 60204-1,Ed. 5.1 2009, Safety of Machinery -Electrical equipment of Machines - Part 1:
General Requirements
IEC 60364-4-44, Ed. 2.0 2007, Low-voltage Electrical Installations; Part 4-44: Protection for
safety - Protection against voltage disturbances and electromagnetic disturbances.
IEC 61140, Ed. 3.1 2009, Protection Against Electric Shock - Common Aspects for
Installation and Equipment.
IEC 61326-1 2005, Electrical Equipment For Measurement, Control and Laboratory Use EMC Requirements.
IEC 61511-1 Ed. 1.0 2003, Functional safety - Safety instrumented systems for the process
industry sector - Part 1: Framework, definitions, system, hardware and software
requirements.
EN 61000-3-11 Ed. 1.0, Electromagnetic compatibility (EMC) - Part 3-11: Limits - Limitation
of voltage changes, voltage fluctuations and flicker in public low-voltage supply systems Equipment with rated current ≤ 75 A and subject to conditional connection.
EN 61000-3-12 Ed. 1.0, Electromagnetic compatibility (EMC) - Part 3-12: Limits - Limits for
harmonic currents produced by equipment connected to public low-voltage systems with
input current > 16 A and ≤ 75 A per phase.
76
References
Lightning references
NFPA 780, Standard for the Installation of Lightning Protection Systems, 2011.
NUREG/CR-6866 ORNL/TM-2001/140, Technical Basis for Regulatory Guidance on
Lightning Protection in Nuclear Power Plants, 2011.
Lightning Protection for Engineers, National Lightning Safety Institute, 2009.
77
References
78