1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 6420 Equipment Used for System Isolation and Rated as a Single UnitUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MA
2、TERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Equipment Used for System Isolation and Rated as a Single Unit, UL 6420 First Edition, Dated October 19, 2012 Summary of Topics This rst edition of the Standard for Equipment Used for
3、 System Isolation and Rated as a Single Unit, UL 6420, has been published and reects the rst time ANSI approval as an American National Standard. The new requirements are substantially in accordance with Proposal(s) on this subject dated August 5, 2011 and February 24, 2012. All rights reserved. No
4、part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form by any means, electronic, mechanical photocopying, recording, or otherwise without prior permission of UL. UL provides this Standard as is without warranty of any kind, either expressed or implied, i
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8、asers computer system. The requirements in this Standard are now in effect, except for those paragraphs, sections, tables, gures, and/or other elements of the Standard having future effective dates as indicated in the note following the affected item. The prior text for requirements that have been r
9、evised and that have a future effective date are located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice. OCTOBER 19, 2012 UL 6420 tr1UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL OCTOBER 19, 2012 UL 6420 tr2 No Te
10、xt on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL OCTOBER 19, 2012 1 UL 6420 Standard for Equipment Used for System Isolation and Rated as a Single Unit First Edition October 19, 2012 This ANSI/UL Standard for Safety consists of
11、 the First Edition. The most recent designation of ANSI/UL 6420 as an American National Standard (ANSI) occurred on October 19, 2012. ANSI approval for a standard does not include the Cover Page, Transmittal Pages, Title Page, or effective date information. Comments or proposals for revisions on any
12、 part of the Standard may be submitted to UL at any time. Proposals should be submitted via a Proposal Request in ULs On-Line Collaborative Standards Development System (CSDS) at http:/. ULs Standards for Safety are copyrighted by UL. Neither a printed nor electronic copy of a Standard should be alt
13、ered in any way. All of ULs Standards and all copyrights, ownerships, and rights regarding those Standards shall remain the sole and exclusive property of UL. COPYRIGHT 2012 UNDERWRITERS LABORATORIES INC. ANSI/UL 6420-2012UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTIO
14、N WITHOUT PERMISSION FROM UL OCTOBER 19, 2012 UL 6420 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CONTENTS 1 Scope and Object .5 1.1 Scope .5 1.2 Object .6 2 Normative References .6 3 Denitions 7 4 Classication of t
15、he System Isolation Equipment 8 4.1 General .8 4.2 According to the system design with single or multiple power isolation points 8 4.3 According to the utilization category/load designation .8 4.4 According to the required safety performance 9 4.5 According to the normal load and overload characteri
16、stics .9 4.6 According to the method chosen to monitor the controlled load side power circuit 9 4.7 According to the conguration limits of the lockout station locations (See Annex A, Figures A.2 and A.3) .9 4.8 According to the available machine control interface functions 10 4.9 According to the re
17、set function following restoration of power to the power circuit line terminals .11 5 Characteristics of the System Isolation Equipment (Including the Characteristics of the Self Contained Components that are Used in the Construction of the System Isolation Equipment) .11 5.1 General 11 5.2 Electrom
18、echanical isolating contactor(s) 16 5.3 Connections to internal control circuits .18 5.4 Load side power circuit monitoring methods 20 5.5 Lockout station 21 5.6 Conguration requirements .22 6 Product Information 24 6.1 Nature of information 24 6.2 Marking 25 6.3 Instructions for installation, opera
19、tion and maintenance 25 7 Normal Service, Mounting and Transport Conditions .26 8 Construction and performance requirements 26 8.1 General 26 8.2 Lockout switch actuator (see 8.1.4 of UL 60947-4-1A) .26 8.3 Performance requirements (see 8.2 of UL 60947-4-1A) 31 8.4 Electromagnetic compatibility (EMC
20、) (see 8.3 of UL 60947-4-1A) 42 9 Tests .46 9.1 Kinds of test 46 9.2 Compliance with constructional requirements .53 9.3 Performance 55 9.4 EMC Tests .73 OCTOBER 19, 2012 UL 6420 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Annex A Inten
21、ded Applications (informative) A1 General .A1 A2 Evaluating the application .A1 A3 Typical functions .A2 A3.2 Typical application congurations A4 A3.3 Typical design features of the system isolation equipment A4 Annex B OCTOBER 19, 2012 UL 6420 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REP
22、RODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 1 Scope and Object 1.1 Scope 1.1.1 General 1.1.1.1 This standard applies to isolating equipment incorporating electromechanical contactors remotely controlled and monitored to provide remote isolation status indication with a dened integrity level
23、. This equipment is intended for use as an additional isolating means on the load side of the required supply-disconnecting device and over current protection. This standard applies to isolating equipment that is to be used in circuits of which the rated voltage does not exceed 1000 Vac or 1500 Vdc.
24、 1.1.1.2 The system isolation equipment is expected to be used both as a means for removal of power for prevention of unexpected start-up of a stopped machine and as an isolator to provide protection from electric shock by ensuring the removal of electrical energy. 1.1.1.3 This equipment is intended
25、 for installation in accordance with the National Electrical Code, NFPA 70 and the Electrical Standard for Industrial Machinery, NFPA 79:2012. Note Reference to System Isolation Equipment is found in Article 430.109(A)(7) of the National Electrical Code NFPA 70; in Clause 5.5.4(3), Devices for Disco
26、nnecting (Isolating) Electrical Equipment, of the Electrical Standard for Industrial Machinery, NFPA 79:2012; and in Clause 5.3.2(d) of the Standard for Safety of Machinery Electrical Equipment of Machines Part 1: General Requirements, IEC 60204-1. 1.1.1.4 The System Isolation Equipment is not inten
27、ded to fulll the function of a motor starter or other motion control device. 1.1.2 System isolation equipment 1.1.2.1 Typical application 1.1.2.1.1 The system isolation equipment is principally intended for industrial machine applications where, isolation of power is so frequently required that the
28、mechanical life of a typical disconnecting means is unacceptably short or where there are multiple entry points on the machine where disconnection is required, or both. Note Multiple entry points are a function of access needs and the layout of the machine. OCTOBER 19, 2012 UL 6420 5UL COPYRIGHTED M
29、ATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 1.2 Object 1.2.1 The object of this standard is to state: a) The characteristics of the system isolation equipment; b) The conditions of operation and behavior for the system isolation equipment, its dielectri
30、c properties, and the degree of protection provided by its enclosure where applicable; c) The information to be marked on or given with the system isolation equipment; d) The normal service, mounting and transport conditions of the system isolation equipment; e) The construction and performance of t
31、he system isolation equipment; f) The tests intended to verify that these conditions have been met, and the methods to be adopted for these tests. 2 Normative References 2.1 The following normative documents contain provisions, which, through reference in this text, constitute provisions of this sta
32、ndard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For und
33、ated references, the latest edition of the normative document referred to applies. UL 60947-1 Standard for Low-Voltage Switchgear and Controlgear Part 1: General Rules UL 60947-4-1A Standard for Low-Voltage Switchgear and Controlgear Part 4-1: Contactors and motor-starters Electromechanical contacto
34、rs and motor-starters NFPA 79:2012 Electrical Standard for Industrial Machinery OCTOBER 19, 2012 UL 6420 6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 3 Denitions 3.1 For the purpose of this standard, the denitions of Clause 2 of the Stan
35、dard for Low-Voltage Switchgear and Controlgear Part 1: General Rules, UL 60947-1, and the denitions of Clause 3 of the Standard for Low-Voltage Switchgear and Controlgear Part 4-1A: Contactors and Motor-Starters Electromechanical Contactors and Motor-Starters, UL 60947-4-1A, together with the follo
36、wing denitions apply. 3.2 CONNECTED EQUIPMENT All circuits that are isolated by the system isolation equipment. 3.3 MIRROR CONTACT Normally closed auxiliary contact, which cannot be in closed position simultaneously with the normally open main contact. Note For more information see the Requirements
37、for Auxiliary Contact Linked with Power Contact (Mirror Contact), in the Standard for Low-voltage switchgear and controlgear Part 4-1: Contactors and motor-starters Electromechanical contactors and motor-starters, IEC 60947-4-1, Annex F. One contactor may have more than one mirror contact. 3.4 MONIT
38、ORED CIRCUITS Control circuits that are designed so that their function(s) are checked for failure continuously or at suitable intervals by the control system. 3.5 REDUNDANTLY MONITORED Control circuits that are monitored through the use of multiple path systems. 3.6 STOP CATEGORY1Acontrolled stop w
39、ith power to the machine actuators available to achieve the stop then remove power when the stop is achieved. (Electrical Standard for Industrial Machinery, NFPA 79:2012, Clause 9.2.2, Stop functions.) 3.7 SUPPLY DISCONNECT Disconnecting means to remove incoming power supplied to a machine. 3.8 SYST
40、EM ISOLATION EQUIPMENT Equipment packaged to provide the disconnection/isolation function separate from the supply disconnect and capable of operation from multiple remote locations by means of lockout switches. Each lockout switch is capable of being padlocked in the OFF (open) position. Visual ind
41、ication is provided to the operator at the respective lockout station that is in the OFF (open) position when the power bus is isolated. OCTOBER 19, 2012 UL 6420 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 4 Classication of the System I
42、solation Equipment 4.1 General 4.1.1 This clause lists the characteristics of system isolation equipment. Information about these listed characteristics may be given by the manufacturer but may not necessarily have to be veried by testing, unless such requirements are indicated here or elsewhere in
43、this document. 4.2 According to the system design with single or multiple power isolation points 4.2.1 A single power isolation is accomplished by isolating the power to multiple motors. 4.2.2 A multiple power isolation is accomplished by isolating the power to individual motors, groups of motors or
44、 other loads. 4.3 According to the utilization category/load designation 4.3.1 Although the system isolation equipment is not intended to be used as a motor starter or any other form of motor control, the power components and power circuits shall be appropriate for on-load switching of motors or oth
45、er inductive loads of the connected equipment. The system isolation equipments rating and load designation shall be in accordance with the Standard for Low-Voltage Switchgear and Controlgear Part 4-1A: Contactors and Motor-Starters Electromechanical Contactors and Motor-Starters, UL 60947-4-1A, Tabl
46、e 5.4DV.1. The utilization category/load designation shall be based on the construction and performance requirements found in Clause 8 and testing requirements in Clause 9. 4.3.2 Clause 5.4 of the Standard for Low-Voltage Switchgear and Controlgear Part 4-1A: Contactors and Motor-Starters Electromec
47、hanical Contactors and Motor-Starters, UL 60947-4-1A, applies with the following additions: a) AC23A: Switching of alternating current motor loads or other highly inductive loads (A = frequent use) b) DC23A: Switching of highly inductive direct current loads (e.g. series motors) (A = frequent use) 4
48、.3.3 Only references to contactors in the Standard for Low-Voltage Switchgear and Controlgear Part 4-1A: Contactors and Motor-Starters Electromechanical Contactors and Motor-Starters, UL 60947-4-1A, apply to power control components of system isolation equipment. OCTOBER 19, 2012 UL 6420 8UL COPYRIG
49、HTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 4.4 According to the required safety performance 4.4.1 The system isolation equipment shall be designed to meet the requirements of Clause 5.1.2.4. 4.5 According to the normal load and overload characteristics 4.5.1 Although the system isolation equipment is not intended to be used as a motor starter or any other form of motor control, the power circuit components and po
