Materials System Specification
16-SAMSS-518
Low Voltage Panelboards
24 August 2016
Document Responsibility: Electrical Substations Equipment Stds. Committee
Contents
1
Scope .......................................................... 2
2
Conflicts and Deviations .............................. 2
3
References .................................................. 2
4
Definitions .................................................... 3
5
General ........................................................ 4
6
Classified Area Panelboard ......................... 4
7
Service Conditions ....................................... 5
8
Rating .......................................................... 6
9
Enclosures ................................................... 6
10
Conductors .................................................. 7
11
Grounding (Earthing) ................................... 8
12
Switching Devices ....................................... 8
13
Nameplates ................................................. 9
Revision Summary .............................................. 9
Data Schedule 1 ................................................ 10
Previous Issue: 16 June 2013
Next Planned Update: 24 August 2019
Page 1 of 10
Contact: Al-Suwaidan, Hussain Musleh (suwaidhm) on +966-13-8809562
©Saudi Aramco 2016. All rights reserved.
Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
1
16-SAMSS-518
Low Voltage Panelboards
Scope
This specification is based on NEMA PB 1, and UL 67. It defines the mandatory
requirements for low voltage panelboards installed indoors or outdoors. This
specification covers completely enclosed panelboards and also panelboards which are
integrated into switchboards.
Commentary Note:
This specification covers all low voltage panelboards including panelboards for
Uninterruptible Power Supply (UPS) and Direct Current (DC) service.
2
3
Conflicts and Deviations
2.1
If there are any conflicts between this Specification and associated purchasing,
project or engineering documents, this specification shall take precedence.
2.2
Direct all requests to deviate from this Specification in writing to the Company
or Buyer Representative, who shall follow internal company waiver procedure.
2.3
The designation “Commentary” is used to label a sub-paragraph that contains
comments that are explanatory or advisory. These comments are not mandatory,
except to the extent that they explain mandatory requirements contained in this
SAMSS.
References
The following is a summary of all the documents which have been mentioned within
this Specification. The specific part(s) of these documents which are applicable have
been identified throughout this Specification.
3.1
Saudi Aramco References
Saudi Aramco Engineering Standard
SAES-P-100
Basic Power System Design Criteria
Saudi Aramco Materials System Specification
17-SAMSS-516
3.2
Uninterruptible Power Supply System
Industry Codes and Standards
International Electrotechnical Commission
IEC 60529
Degrees of Protection Provided by Enclosures
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
IEC 60947-1
Part 1: General Rules
IEC 60947-2
Part 2: Circuit Breakers
16-SAMSS-518
Low Voltage Panelboards
National Electrical Manufacturers Association
NEMA 250
Enclosures for Electrical Equipment
(1000 Volts Maximum)
NEMA PB 1
Panelboards
Underwriters Laboratories, Inc.
UL 67
4
Panelboards
Definitions
Conductor: All material, devices and parts, which are expected to carry current as part
of their normal function.
Copper Free: 0.4 of 1% maximum copper content.
Explosionproof Panelboard: multiple breakers housed in an explosionproof overall
enclosure designed to control the explosion inside the enclosure.
Flameproof Panelboard: Multiple breakers housed in a non-explosionproof overall
enclosure breakers. Breakers are either in individual explosionproof enclosures or are of
flameproof design.
Low Voltage: Means a voltage level of less than 1000 volts.
Main Circuit: All the conductive parts of an assembly included in a circuit, which is
intended to transmit electrical energy to the connected loads.
Commentary Note:
Note that, “main circuit” includes the panelboard neutral conductor system.
Main Circuit Disconnector: Device to isolate the panelboard from the main incoming
circuit.
Commentary Note:
Frame size and trip rating is selected by the panelboard manufacturer to meet the
requirement in this specification that the disconnector allow the full capacity of the bus to
be utilized.
PEM: Parent Equipment Manufacturer. The manufacturer who designed the
equipment and who confirmed the design performance through certified design/type
tests. This manufacturer (1) has the legal authority to license the assembly of this
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
16-SAMSS-518
Low Voltage Panelboards
equipment to others (2) is responsible for the technical performance of the equipment
and (3) will be able to provide after-sales support and parts for the equipment.
Plastic: General term, which includes all non-metallic material, including fiberglass.
Switching Device: A device designed to make or break current.
5
General
5.1
Terms in bold font are defined within Section 4.
5.2
Panelboards shall fully comply with NEMA PB 1 and UL 67.
Exception to 5.2:
Flameproof panelboards shall comply with the relevant IEC standards.
6
5.3
All requirements of this specification must be implemented using standard
designs which have been approved, have been fully tested, and are fully
supported by the PEM.
5.4
Whenever this specification requires compliance to a third party document
(e.g., ANSI, UL,IEC, etc.), this document shall be the edition which was in
effect on the date of the Quotation Request.
5.5
This specification shall take precedence over any referenced third party
document.
5.6
For panelboards which provide branch circuits operating at phase-to-neutral
voltage levels, a neutral bus shall be provided within the panelboard.
5.7
All temperatures expressed within this specification are in Celsius units.
5.8
(Modification) to NEMA PB 1, Section 2.1 and UL 67, Section 6.2.1:
No equipment other than circuit breakers shall be allowed in panelboards.
Classified Area Panelboard
6.1
If specified in Data Schedule 1 as being installed in an electrically classified
area, panelboards shall comply with the following requirements:
6.1.1
(Addition) to NEMA PB and UL 67: Panelboards shall be of either the
following designs:
a)
Explosionproof panelboard, design with the branch circuit
connections and the breaker in separate compartments is required.
The panel shall be completely filled with breakers.
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
b)
6.1.2
7
16-SAMSS-518
Low Voltage Panelboards
Flameproof panelboard, the internal line, and load connectors to
the breakers shall be factory wired.
(Addition) to NEMA PB 1 and UL 67: The branch circuit connection,
inclusive of spares, shall be terminated on terminal blocks within the
termination compartment. The neutral and ground buses shall be within
this compartment.
Service Conditions
7.1
Panelboards installed indoors shall be suitable for continuous operation under
the following service conditions:
7.1.1
7.1.2
7.2
Ambient air temperature:
a)
A maximum of 40°C
b)
(Modification) to NEMA PB 1, Section 2.6 and UL 67, Section 19.1:
A minimum of 0°C.
c)
Average temperature, measured over a period of 1 month, is a
maximum of 35°C.
Relative humidity (average value).
a)
For a period of 24 hours, does not exceed 95%.
b)
For a period of 1 month, does not exceed 90%.
Panelboards installed outdoors shall be suitable for continuous operation under
the following service conditions:
7.2.1
Ambient air temperature:
a)
(Addition) to NEMA PB 1 and UL 67: A maximum of 50°C.
b)
(Addition) to NEMA PB 1 and UL 67: A minimum of 0°C, unless a
lower temperature is specified within Data Schedule 1.
c)
(Addition) to NEMA PB 1 and UL 67: Average temperature,
measured over a period of 1 month, is a maximum of 45°C.
7.2.2
(Modification) to NEMA PB 1, Section 2.6: (Addition) to UL 67:
Altitude is less than 1000 meters, unless a higher altitude is specified
within Data Schedule 1.
7.2.3
Average value of the relative humidity:
a)
(Addition) to NEMA PB 1 and UL 67: For a period of 24 hours,
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
16-SAMSS-518
Low Voltage Panelboards
does not exceed 95%
b)
7.3
8
(Addition) to NEMA PB 1 and UL 67: For a period of 1 month,
does not exceed 90%.
7.2.4
(Addition) to NEMA PB 1 and UL 67: Relative humidity may be
temporarily 100%.
7.2.5
(Addition) to NEMA PB 1 and UL 67: Exposure to the following:
a)
Air-borne dust concentration of 1 mg/m³ with 95% of all particles
less than 20 micrometers in diameter. “Dust” includes compounds
of calcium, sodium, magnesium, silicon, and aluminum.
b)
Pollutants such as H2S - 20 ppm, SO2 - 10 ppm, CO - 75 ppm,
NOX - 5 ppm, hydrocarbons - 100 ppm, NaCl - 300 ppm and
MgCl - 50 ppm.
(Addition) to NEMA PB 1 and UL 67: Panelboards shall be suitable for
installation within the Electrical Area Classification indicated within Data
Schedule 1. Refer to Section 5 for additional design criteria for these
panelboards.
Rating
8.1
Rated Duty: Continuous.
8.2
(Modification) to NEMA PB 1, Section 2.10 and UL 67, Section 10.4:
Rated Current (minimum): 100A
Exception to 8.2:
63 A is the minimum current rating for the flameproof panelboards.
8.3
9
(Modification) to NEMA PB 1, Section 3.5 and UL 67, Section 31.1.1:
Short Circuit interrupting rating (minimum): 10 kA rms
Enclosures
9.1
Enclosures shall bear labels from a third party testing laboratory (i.e., UL, CSA,
BASEEFA, KEMA, etc.) indicating that they are designed, constructed and
tested to the applicable standards referenced within this specification.
9.2
Enclosures of panelboards installed outdoors shall have the following
characteristics:
9.2.1
When “severe corrosive environment” is specified within Data Schedule 1,
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
16-SAMSS-518
Low Voltage Panelboards
the enclosure design shall be either:
a)
Type 4X per NEMA 250.
Exception to 9.2.1:
Galvanized and/or painted or coated carbon steel sheet metal
material shall not be used.
(Modification) to NEMA PB 1, Section 5.8.1 and UL 67 Section
11A.2.4: Type 3 or 4 per NEMA 250 and manufactured of copper
free cast aluminum or plastic.
c)
IP6X per IEC 60529 and manufactured of stainless steel, copper free
cast aluminum or plastic.
If a “severe corrosive environment”, is not specified, it is acceptable that
the panelboard enclosure meet the requirements of either:
9.2.2
9.2.3
9.3
b)
a)
(Modification) to NEMA PB 1, Section 5.8 and UL 67 Section
11A.2.4: Type 4, 4X, 6, 6P, 3/7, 4/7 or 4X/7 per NEMA 250.
b)
(Modification) to NEMA PB 1, Section 5.8.1 and UL 67 Section
11A.2.4: Type 3 per NEMA 250 and manufactured of copper free
cast aluminum, plastic or galvanized carbon sheet metal.
c)
IPYX per IEC 60529. Where ‘Y’ shall be the numeral ‘5’ or ‘6’ and
‘X’ shall be a numeral between ‘4’ and ‘8’ inclusive.
(Addition) to NEMA PB 1 and UL 67: Enclosures rated Type 3, 4 or 4X
per NEMA 250 shall be equipped with Type 300 Series stainless steel
hardware.
(Addition) to NEMA PB 1 and UL 67: Panelboards specified as being installed
outdoors and having and internal volume exceeding 2,000 cm³ shall be provided
with Type 300 Series stainless steel breather and drain fittings.
Exception to 9.3:
Thin wall (sheet metal or plastic) enclosures may be drained by drilling a 5 mm
hole in the bottom of the enclosure.
10
Conductors
10.1
(Modification) to NEMA PB 1, Section 5.3.3.4 and UL 67, Section 10.1.1:
All conductors shall be copper, silver, or alloys of these materials with the
following exceptions:
10.1.1 Parts which are internal to a pre-manufactured device (e.g., internals
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
16-SAMSS-518
Low Voltage Panelboards
circuit breaker).
10.1.2 Connectors supplied as integral parts or components of manufactured
equipment such as molded case circuit breakers provided the connectors
are approved for copper conductors.
10.1.3 Plating of the copper, silver, or copper/silver alloy base conductor
material is acceptable.
10.2
11
The main circuit bus system shall be of rigid material (i.e., cable or flexible
conductors shall not be used).
Grounding (Earthing)
A ground bus shall be provided within the panelboard.
12
Switching Devices
12.1
(Addition) to NEMA PB 1 and UL 67: If the breaker size is not specified within
the purchasing documents, breakers shall have a minimum trip rating of 20 A.
12.2
(Addition) to NEMA PB 1 and UL 67: Breakers operating at greater than
240 Volts shall be equipped with padlockable lock-off devices.
12.3
(Addition) to NEMA PB 1 and UL 67: Tandem, twin, or half-size breakers shall
not be used.
12.4
(Addition) to NEMA PB 1 and UL 67: When main circuit disconnectors are
used, they shall be sized to allow the main bus to be operated at its full current
rating.
12.5
(Addition) to NEMA PB 1 and UL 67: Panelboards shall be equipped with a
minimum of 10% spare breakers and a minimum of 10% spare pole spaces.
If not indicated in the engineering documents, the sizes of the spare breakers
shall be representative of the connected breakers within the panelboards.
Exception to 12.5:
The explosionproof panelboards shall be completely filled with breakers.
12.6
(Modification) to NEMA PB 1, Section 2.8.1 and UL 67, Section 13.1:
Ground fault protective functions shall not be installed on any incoming or
outgoing circuits.
Exception:
Branch circuit Ground fault Circuit Interrupters (GFCIs) with nominal 5 mA trip
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
16-SAMSS-518
Low Voltage Panelboards
levels or Equipment Protection Devices (EPDs) with nominal 30 mA trip level or
residual current devices (RCDs) with 5 to 30 ma trip levels are allowed.
13
Nameplates
(Modification) to NEMA PB 1, Section 5.1.1 and UL 67, Section 32: White Nameplates
with black lettering shall be provided to identify the panelboard with the tag number
indicated within Data Schedule 1.
Revision Summary
24 August 2016
Major revision per the management directive to optimize company standards by maximizing
alignment with international standards.
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Document Responsibility: Electrical Substations Equipment Standards Committee
Issue Date: 24 August 2016
Next Planned Update: 24 August 2019
16-SAMSS-518
Low Voltage Panelboards
Data Schedule 1
For 16-SAMSS-518: Low Voltage Panelboards
(Information to be supplied to Supplier)
Line #
1
Buyer’s Quotation Request/ Purchase Order No.
______________________________________________________
2
Buyer’s B.I./J.O. No.________, Line Item No.___________
3
Panelboard Tag No.__________________________
Service information:
20
Indoor: _____, Outdoor _____
22
Electrical Area Classification: Unclassified ____
23
Classified ____: Class ___ Division ___, Group(s) ____ or Class ___ Zone ___, Group(s) ___
30
Severe Corrosive Environment(1): YES ___, NO ___
33
System frequency:
60 Hz _____, 50 Hz _____, DC _____
If AC, Number of Phases/Wires 1/2___, 1/3___, 3/3 ____, 3/4 ___
35
UPS service: YES ___, NO ____
40
Rated Current:
43
Rated Voltage: _______________
50
Minimum ambient air temperature (if lower than 0°C) _______ °C
53
Site altitude (if greater than 1000 meters) _________ meters
70
Neutral bus required:
72
_______ A 41
Short Circuit Interrupting Rating: _________ kA (10 kA minimum)
YES ___, NO ___
If YES, rated current of neutral bus as a % of phase bus: 100% ___, 200% ___
74
Main circuit disconnector required: YES ___, NO ____:
76
Main circuit supply conductor connectors (if applicable): Supplied by Supplier: YES ( ), NO ( )
77
If YES: No./phase and size of main circuit supply conductors:
78
79
_____ /ph., ______ AWG, MCM, mm²
Branch circuit breaker requirements:
Quantity
Poles
Trip Rating
_________________________________
_________________________________
_________________________________
_________________________________
_________________________________
80
81
82
83
84
85
OR
Notes to Buyer:
_____
(1)
refer to the engineering documents
Refer to SAES-P-100 for definition of Severe Corrosive Environment.
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