1、NEMA Standards PublicationNational Electrical Manufacturers AssociationANSI/NEMA PB 2.1-2013General Instructions for Proper Handling, Installation, Operation, and Maintenance of Deadfront Distribution Switchboards Rated 600 Volts or LessANSI/NEMA PB 2.1-2013 General Instructions for Proper Handling,
2、 Installation, Operation, and Maintenance of Deadfront Distribution Switchboards Rated 600 Volts or Less Published by National Electrical Manufacturers Association 1300 North 17th Street, Suite 900 Rosslyn, Virginia 22209 www.nema.org Approved: September 13, 2013 2014 National Electrical Manufacture
3、rs Association. All rights, including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention for the Protection of Literary and Artistic Works, and the International and Pan American copyright conventions. 2014 National Electrical Manufacturers Asso
4、ciation NOTICE AND DISCLAIMER (ANSI Accredited Standards Committee) The information in this publication was considered technically sound by the consensus of persons engaged in the development and approval of the document at the time it was developed. Consensus does not necessarily mean that there is
5、 unanimous agreement among every person participating in the development of this document. ANSI standards, of which the document contained herein is one, are developed through a voluntary consensus standards development process. This process brings together volunteers and/or seeks out the views of p
6、ersons who have an interest in the topic covered by this publication. As Secretary of the ANSI Accredited Standards Committee, NEMA administers the process in accordance with the procedures of the American National Standards Institute to promote fairness in the development of consensus. As a publish
7、er of this document, NEMA does not write the document and it does not independently test, evaluate or verify the accuracy or completeness of any information or the soundness of any judgments contained in its standards and guideline publications. NEMA disclaims liability for any personal injury, prop
8、erty or other damages of any nature whatsoever, whether special, indirect, consequential or compensatory, directly or indirectly resulting from the publication, use of, application, or reliance on this document. NEMA disclaims and makes no guaranty or warranty, express or implied, as to the accuracy
9、 or completeness of any information published herein, and disclaims and makes no warranty that the information in this document will fulfill any of your particular purposes or needs. NEMA does not undertake to guarantee the performance of any individual manufacturers or sellers products or services
10、by virtue of this standard or guide. In publishing and making this document available, NEMA is not undertaking to render professional or other services for or on behalf of any person or entity. Nor is NEMA undertaking to perform any duty owed by any person or entity to someone else. Anyone using thi
11、s document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances. Information and other standards on the topic covered by this publication may be available from othe
12、r sources, which the user may wish to consult for additional views or information not covered by this publication. NEMA has no power, nor does it undertake to police or enforce compliance with the contents of this document. NEMA does not certify, test or inspect products, designs or installations fo
13、r safety or health purposes. Any certification or other statement of compliance with any health or safetyrelated information in this document shall not be attributable to NEMA and is solely the responsibility of the certifier or maker of the statement. PB 2.1-2013 Page i 2014 National Electrical Man
14、ufacturers Association TABLE OF CONTENTS Page Foreword iv Section 1 GENERAL 1 1.1 Scope . 1 1.2 References 1 1.3 General 1 1.3.1 Successful Operation 2 1.3.2 Qualified Personnel . 2 1.3.3 Definition of Qualified Personnel . 2 Section 2 HANDLING 3 2.1 Manufacturers Handling Instructions 3 2.2 Care to
15、 Avoid Damage 3 2.3 Upright Position . 3 2.4 Equipment Capacity . 3 2.5 Concealed Damage . 3 2.6 Storage Prior to Installation . 3 2.7 Shipping Skid . 3 2.8 Rod or Pipe Rollers 3 2.9 Forklift Truck 3 2.10 Overhead Hoisting . 4 2.10.1 Rigid Spreaders or Spanner Bars . 4 2.10.2 Rigging Lengths. 4 2.10
16、.3 Angle Between Lifting Cables and Vertical 4 2.10.4 Slings With Safety Hooks or Shackles 4 2.10.5 Removal of Switchboard Top Covers 4 Section 3 STORAGE . 7 3.1 Clean, Dry Space Having Uniform Temperature . 7 3.2 Protection from Weather and Dirt 7 3.3 Outdoor Switchboards are Not Weather Resistant
17、Until Installed . 7 3.4 Un-Energized Outdoor Switchboard Should Be Kept Dry Internally 7 Section 4 INSTALLATION OF SWITCHBOARD OR ENCLOSURE 8 4.1 Manufacturers Installation Instructions . 8 4.2 Location . 8 4.2.1 Clearance from Walls 8 4.2.2 Working Clearances 8 4.3 Channel Sills 8 4.4 Conduit and O
18、ther Raceways 8 4.5 Leveling and Securing . 8 4.6 Splice Bus 8 4.7 Grounding and Bonding . 9 4.7.1 Grounded Systems 9 4.7.2 Ungrounded SystemsService Equipment or Separately Derived System Main. 9 4.7.3 Grounded or Ungrounded Systems . 9 4.8 Unused Openings 10 4.9 Damp Indoor Locations 10 4.10 Unusu
19、al Service Conditions . 10 Section 5 INSTALLATION OF CONDUIT AND CONDUCTORS . 11 5.1 Prevent Moisture or Water from Entering 11 5.2 Temperature Ratings . 11 5.3 Compression (Crimp) Terminals . 11 5.4 Stripping Insulation from Conductors 11 5.5 Proper Wiring Methods 11 PB 2.1-2013 Page ii 2014 Nation
20、al Electrical Manufacturers Association 5.6 Conductor Location in Switchboard . 11 5.7 Conductors 1/0 AWG in Size and Larger 11 5.8 Incoming and Outgoing Control Connections 12 5.9 Prevent Conductor Insulation from Cracking or Splitting . 12 5.10 National Electrical Code, Section 725.54 12 Section 6
21、 INSTALLATION OF SWITCHBOARD INTERIOR 13 6.1 Instructions if Switchboard Interior Was Not Factory-Mounted . 13 6.2 Unpacking 13 6.3 Inspection 13 6.4 Storage 13 6.5 Cleaning . 13 6.6 Manufacturers Instructions 13 6.7 Interior Installation . 13 Section 7 STEPS TO BE TAKEN BEFORE ENERGIZING 14 7.1 Acc
22、essible Electrical Connections . 14 7.2 Blocks or Other Temporary Holding Means 14 7.3 Integrity of All Bus Mounting Means 14 7.4 Enclosure . 14 7.5 Operating Mechanisms 14 7.6 Electrical Insulation Resistance Test . 14 7.7 Electrical Relays, Meters, and Instrumentation . 14 7.8 Electrically Operate
23、d Switches, Circuit Breakers, and Other Mechanisms . 14 7.9 Ground Fault Protection System 15 7.10 Adjustable Time Current Trip Device Settings . 15 7.11 Field Wiring 15 7.12 Grounding Connections . 15 7.13 Foreign Material . 15 7.14 Covers and Doors 15 Section 8 ENERGIZING EQUIPMENT 16 8.1 Qualifie
24、d Personnel Present 16 8.2 No Load on Switchboard . 16 8.3 Energized in Sequence 16 8.4 After All Main, Feeder, and Branch Circuit Devices Have Been Closed 16 Section 9 MAINTENANCE 17 9.1 Maintenance Program for Switchboards . 17 9.2 Field Test . 17 9.3 Switchboard Inspection Once Each Year 17 9.4 A
25、ccumulation of Dust and Dirt . 17 9.4.1 All Visible Electrical Joints and Terminals . 17 9.4.2 All Conductors and Connections . 17 9.4.3 Fuse Clip Contact Pressure and Contact Means 18 9.4.4 All Conditions Which Caused Overheating . 18 9.5 Proper Ampere, Voltage, and Interrupting Ratings 18 9.5.1 Al
26、l Mechanisms Are Free and in Proper Working Order . 18 9.6 Operation of All Mechanical Components . 18 9.6.1 Full On and Off Positions 18 9.6.2 Integrity of Electrical and Mechanical Interlocks . 18 9.6.3 Missing or Broken Parts 18 9.6.4 Manufacturers Instructions . 18 9.6.5 Readily Accessible Coppe
27、r Electrical Contacts, Blades, and Jaws 19 9.7 Deteriorated Insulating Material and Assemblies 19 9.8 Moisture or Signs of Previous Wetness. 19 9.8.1 Conduits Which Have Dripped Condensate 19 PB 2.1-2013 Page iii 2014 National Electrical Manufacturers Association 9.8.2 Cracks or Openings. 19 9.8.3 I
28、nsulating Material Which is Damp 19 9.8.4 Moisture Damaged Component Device 19 9.9 Water Damage 19 9.10 Severe Electrical Short Circuit . 19 9.11 Ground Fault Protection System 20 9.12 Insulation Resistance . 20 Section 10 PERMISSIBLE LOADING OF SWITCHBOARDS 21 10.1 Switchboards Without Main Overcur
29、rent Protective Devices 21 10.2 Switchboards With a Single Main Overcurrent Protective Device . 21 10.3 Switchboards With a Multiple Main Overcurrent Protective Device . 21 10.4 Feeder and Branch Circuit Overcurrent Protective Devices in Switchboards . 21 10.5 Harmonics in the Electrical System . 21
30、 Figures 2-1 LIFTING WITH EYE BOLTS . 5 2-2 LIFTING WITH INTEGRAL LIFT ANGLE 5 2-3 LIFTING WITH SLING RIGGING 6 PB 2.1-2013 Page iv 2014 National Electrical Manufacturers Association Foreword This publication is a guide of practical information containing instructions for the proper handling, instal
31、lation, operation, and maintenance of deadfront distribution switchboards rated 600 Volts or less. These instructions do not purport to cover all details or variations in equipment, nor to provide for every possible contingency regarding handling, installation, operation, or maintenance. It is recom
32、mended that work described in this set of instructions be performed only by qualified personnel familiar with the construction and operation of switchboards and that such work be performed only after reading this complete set of instructions. For specific information not covered by these instruction
33、s, you are urged to contact the manufacturer of the switchboard directly. PB 2.1-2013 revises and supersedes PB 2.1-2007. In the preparation of this standards publication input of users and other interested parties has been sought and evaluated. Inquiries, comments, and proposed or recommended revis
34、ions should be submitted to the concerned NEMA product section by contacting the following: Senior Technical Director, Operations National Electrical Manufacturers Association 1300 North 17th Street, Suite 900 Rosslyn, Virginia, 22209 This standards publication was developed by the Panelboard and Di
35、stribution Board Section. Section approval of the standard does not necessarily imply that all section members voted for its approval or participated in its development. At the time it was approved, the Panelboard and Distribution Board Section was composed of the following members: Eaton Corporatio
36、n.Pittsburgh, PA GE Industrial SolutionsPlainville, CT Hubbell, Inc.Bridgeport, CT Milbank Manufacturing CompanyKansas City, MO Penn Panel U S ES L I N G S W I T HS A F E T Y H O O K SO R S H A C K LE SD O N T P A S SR O P E S O R C A B LE ST H R O U G H LI F TH O L E S ; U S ES LI N G S W I T HS A
37、F E T Y H O O K SO R S H A C K L E SS P A N N E R B A R( C H A N N E L)B L O C K SS H I P P I N G S K I DS W I T C H B O A R DS W I T C H B O A R DS W I T C H B O A R DT H E H E I G H T O F T H EL I F T P O I N T A B OV ET H E L IF T A N G L ES H OU L D B E A T L E A S T1 / 2 O F “ A “ ( T H ED IS T
38、 A N C E B E T W E E NL I F T H O L E S ) . T H ISA S S U R E S A M A X I -M U M A N G L E OF4 5 A S S H O W NoT H E H E IG H T O F T H E L I F T P O IN TA B O V E T H E S P R E A D E R S H O U L DB E A T L E A S T 1 /2 O F “ A “( T H E D IS T A N C E B E T W E E N E Y E -B O L T S ) . T H IS A S S
39、U R E S A M A X I -M U M A N G L E O F 4 5 A S S H O W NoLI F T H O LEE Y E B O L T SL I F T A N G L ES P R E A D E RL I F T P O I N TL I F T P O I N TF ig u re 1 L i f t i n g w i t h E y e B o lt sF i g u r e 2 L i f t i n g w i t h I n t e g ra l L i f t A n g l eF i g u r e 3 L if t in g w i t h
40、 S l i n g Ri g g i n gFigure 2-1 LIFTING WITH EYE BOLTS Figure 2-2 LIFTING WITH INTEGRAL LIFT ANGLE PB 2.1-2013 Page 6 2014 National Electrical Manufacturers Association M A X45oM A X45oM A X45oAAA1/ 2 AO R MO R ED O N T P A S SR O P E S O R C A B L E ST H R O U G H L I F TH O LE S ; U S ES L I N G
41、 S W I T HS A F E T Y H O O K SO R S H A C K LE SD O N T P A S SR O P E S O R C A B LE ST H R O U G H LI F TH O L E S ; U S ES LI N G S W I T HS A F E T Y H O O K SO R S H A C K L E SS P A N N E R B A R( C H A N N E L)B L O C K SS H I P P I N G S K I DS W I T C H B O A R DS W I T C H B O A R DS W I
42、T C H B O A R DT H E H E I G H T O F T H EL I F T P O I N T A B OV ET H E L IF T A N G L ES H OU L D B E A T L E A S T1 / 2 O F “ A “ ( T H ED IS T A N C E B E T W E E NL I F T H O L E S ) . T H ISA S S U R E S A M A X I -M U M A N G L E OF4 5 A S S H O W NoT H E H E IG H T O F T H E L I F T P O IN
43、TA B O V E T H E S P R E A D E R S H O U L DB E A T L E A S T 1 /2 O F “ A “( T H E D IS T A N C E B E T W E E N E Y E -B O L T S ) . T H IS A S S U R E S A M A X I -M U M A N G L E O F 4 5 A S S H O W NoLI F T H O LEE Y E B O L T SL I F T A N G L ES P R E A D E RL I F T P O I N TL I F T P O I N TF
44、ig u re 1 L i f t i n g w i t h E y e B o lt sF i g u r e 2 L i f t i n g w i t h I n t e g ra l L i f t A n g l eF i g u r e 3 L if t in g w i t h S l i n g Ri g g i n gFigure 2-3 LIFTING WITH SLING RIGGING PB 2.1-2013 Page 7 2014 National Electrical Manufacturers Association Section 3 STORAGE 3.1
45、CLEAN, DRY SPACE HAVING UNIFORM TEMPERATURE A switchboard that is not installed and energized immediately should be stored in a clean, dry space having a uniform temperature to prevent condensation. Preferably, it should be stored in a heated building having adequate air circulation and protected fr
46、om dirt, fumes, water, and physical damage. 3.2 PROTECTION FROM WEATHER AND DIRT It is recommended that switchboards should not be stored outdoors. However, if it must be stored outdoors, cover it securely to provide protection from weather and dirt. Temporary electrical heating should be installed
47、to prevent condensation; approximately 250 watts per section is adequate for the average switchboard size and environment. All loose packing or flammable materials inside the switchboard should be removed before energizing space heaters. 3.3 OUTDOOR SWITCHBOARDS ARE NOT WEATHER RESISTANT UNTIL INSTA
48、LLED Outdoor switchboards are not weather resistant until completely and properly installed and should be treated exactly the same as indoor switchboards until after they are installed. 3.4 UN-ENERGIZED OUTDOOR SWITCHBOARD SHOULD BE KEPT DRY INTERNALLY An un-energized outdoor switchboard should be k
49、ept dry internally by installing temporary heating (see 3.2) or by energizing any self-contained space heaters. PB 2.1-2013 Page 8 2014 National Electrical Manufacturers Association Section 4 INSTALLATION OF SWITCHBOARD OR ENCLOSURE 4.1 MANUFACTURERS INSTALLATION INSTRUCTIONS Install the switchboard in a neat and workmanlike manner following the manufacturers installation instructions, if available. 4.2 LOCATION Locate the switchboard in the area indicated on the building plans. The switchboard enclosure should be suitable for the environment or protected
