1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 977 Fused Power-Circuit DevicesUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER RE
2、PRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Fused Power-Circuit Devices, UL 977 Fifth Edition, Dated April 30, 2012 Summary of Topics: This new edition of ANSI/UL 977 is being issued to include the following topic: Revisions to Add Non-Fusible Tie Switches to App
3、licable Requirements This Standard also includes editorial revisions such as renumbering and pagination. These revisions are considered to be non-substantive and not subject to ULs STP process. The new requirements are substantially in accordance with Proposal(s) on this subject dated October 7, 201
4、1 and December 23, 2011. All rights reserved. No 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 war
5、ranty of any kind, either expressed or implied, including but not limited to, the implied warranties of merchantability or tness for any purpose. In no event will UL be liable for any special, incidental, consequential, indirect or similar damages, including loss of prots, lost savings, loss of data
6、, or any other damages arising out of the use of or the inability to use this Standard, even if UL or an authorized UL representative has been advised of the possibility of such damage. In no event shall ULs liability for any damage ever exceed the price paid for this Standard, regardless of the for
7、m of the claim. Users of the electronic versions of ULs Standards for Safety agree to defend, indemnify, and hold UL harmless from and against any loss, expense, liability, damage, claim, or judgment (including reasonable attorneys fees) resulting from any error or deviation introduced while purchas
8、er is storing an electronic Standard on the purchasers 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.
9、 The prior text for requirements that have been revised and that have a future effective date are located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice. The following table lists the future effective dates with the corresponding reference. APRIL 30, 2012 UL 977 tr1UL COPYR
10、IGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Future Effective Date Reference October 31, 2013 Paragraphs 1.10 and 25.3. APRIL 30, 2012 UL 977 tr2UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FR
11、OM UL April 30, 2012 1 UL 977 Standard for Fused Power-Circuit Devices First Edition June, 1973 Second Edition October, 1976 Third Edition June, 1984 Fourth Edition November, 1994 Fifth Edition April 30, 2012 This ANSI/UL Standard for Safety consists of the Fifth Edition. The most recent designation
12、 of ANSI/UL 977 as an American National Standard (ANSI) occurred on April 30, 2012. ANSI approval for a standard does not include the Cover Page, Transmittal Pages, Title Page, or effective date information. The Department of Defense (DoD) has adopted UL 977 on August 28, 1984. The publication of re
13、vised pages or a new edition of this Standard will not invalidate the DoD adoption. Comments or proposals for revisions on any 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
14、) at http:/. ULs Standards for Safety are copyrighted by UL. Neither a printed nor electronic copy of a Standard should be altered 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
15、UNDERWRITERS LABORATORIES INC. ANSI/UL 977-2012UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL APRIL 30, 2012 FUSED POWER-CIRCUIT DEVICES - UL 977 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTR
16、IBUTION WITHOUT PERMISSION FROM UL CONTENTS INTRODUCTION 1 Scope .5 2 Components 6 3 Units of measurement .7 4 References .7 CONSTRUCTION 5 General 7 6 Enclosure 9 6.1 General .9 6.2 Rainproof enclosures .9 7 Ventilation 11 8 Sheet-Metal Enclosures 12 9 Doors and Covers .12 10 Hinges 14 11 Latches 1
17、4 12 Operating Mechanism .15 12.1 General .15 12.2 Electrical operators .16 13 Ground Fault Protection .17 14 Insulating Material 19 15 Current-Carrying Parts 19 16 Wiring Terminals 20 17 Control Circuit 21 18 Lockout 21 19 Fusing .21 20 Spacings 26 21 Wiring Space .27 22 Disconnecting Means .30 23
18、Provision for Grounding .31 24 Provision for Bonding .31 PERFORMANCE 25 General 32 26 Temperature Test .35 27 Strength of Insulating Base and Support .37 28 Overvoltage Test .38 29 Water Spray Test .38 30 Operation Test .38 31 Endurance Test 41 32 200-Percent Overload .41 33 Dielectric Voltage-Withs
19、tand Test .42 34 Close-Open Test .44 35 Dielectric Voltage-Withstand (Repeated) Test After the Close-Open Test 45 36 Contact Opening Test .45 37 Dielectric Voltage-Withstand (Repeated) Test After the Contact Opening Test 46 38 Short-Circuit Withstand Test .46 APRIL 30, 2012 FUSED POWER-CIRCUIT DEVIC
20、ES - UL 977 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 39 Closing Test .50 40 Low-Level Dielectric Voltage-Withstand Test .51 41 Metallic Coating Thickness Test 51 INSTRUMENTATION AND CALIBRATION OF HIGH-CAPACITY CIRCUITS 42 Galvanomet
21、ers .52 43 Circuit Measurement Verication 53 44 Calibration of Test Circuit 54 44.1 Details 54 44.2 Current .54 44.3 Voltage .56 44.4 Power factor .56 44.5 Recovery voltage .56 MANUFACTURING AND PRODUCTION TEST 45 Operation 58 RATINGS 46 Current 59 47 Voltage 59 48 Withstand 60 49 Control Circuit 60
22、 MARKING 50 Details .60 INSTALLATION TEST PROCEDURES 51 Details .64 APPENDIX A Standards for ComponentsA1 APRIL 30, 2012 FUSED POWER-CIRCUIT DEVICES - UL 977 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL INTRODUCTION 1 Scope 1.1 These req
23、uirements cover fused power-circuit devices to be employed in accordance with the National Electrical Code. 1.2 Fused power-circuit devices, as covered by these requirements, are considered to be either bolted pressure contact switches or high-pressure butt-type contact switches. 1.3 Bolted-pressure
24、 contact switches are devices in which the blade-jaw connections have an additional pressure or clamping action provided at both ends of the switch blades when the blades are in the fully closed position. 1.4 High-pressure butt-type contact switches are devices having butt-type contacts and a spring
25、-charged mechanism. 1.5 These requirements do not apply to low-voltage AC power circuit protectors as covered by the Standard for Low Voltage AC Power Circuit Protectors Used in Enclosures, ANSI/IEEE C37.29, or to low-voltage AC integrally fused power circuit breakers as covered by the Standard for
26、Low-Voltage AC Power Circuit Breakers Used in Enclosures, ANSI/IEEE C37.13. 1.6 Fused power-circuit devices may be manually or electrically operated and may incorporate electrical tripping means. 1.7 An electrically tripped device is one whose closing is performed manually or electrically but contac
27、t opening is performed by a release energized by a separate source of voltage. 1.8 A device with an electrical operator is one whose contact closing and opening is performed by electrical means. 1.9 Fused power-circuit devices have continuous current ratings of more than 600 A and voltage ratings of
28、 600 V or less AC, DC, or both. Devices rated AC are intended for use on circuits having maximum available short-circuit currents of 100,000, 150,000, or 200,000 A (rms symmetrical). Devices rated DC are intended for use on circuits having maximum available short-circuit currents of 20,000, 50,000,
29、100,000, 150,000, or 200,000 A DC. 1.10 Fused power-circuit devices have provisions for mounting (or are intended to be used with upstream) Class L fuses or Class T fuses rated more than 600 A. 1.10 effective October 31, 2013 1.11 These requirements cover complete, enclosed fused power-circuit devic
30、es in which the switch is integral with the enclosure; open-type fused power-circuit devices intended for mounting in other equipment, such as switchboards or in a separately shipped enclosure; and enclosures intended for mounting open-type fused power-circuit devices. APRIL 30, 2012 FUSED POWER-CIR
31、CUIT DEVICES - UL 977 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 1.12 These requirements also cover electrically tripped and/or operated devices that have been investigated to determine their acceptability for ground-fault protection w
32、hen combined with ground-fault sensing and relaying equipment as follows: a) Switches for use with Class I ground-fault sensing and relaying equipment including those devices that are capable of interrupting 12 times their rated current or that have integral means intended to prevent disconnecting a
33、t levels of fault current exceeding the contact interrupting capability of the switch. b) Switches for use with Class II ground-fault sensing and relaying equipment are capable of interrupting at 10 times their rated current and are for use in ground-fault protection systems where means intended to
34、prevent disconnecting levels at fault current exceeding the contact interrupting capabilities of the switch are incorporated within the ground-fault sensing and relaying equipment. 1.13 A product that contains features, characteristics, components, materials, or systems new or different from those c
35、overed by the requirements in this standard, and that involves a risk of re, electric shock, or injury to persons shall be evaluated using the appropriate additional component and end-product requirements to determine that the level of safety as originally anticipated by the intent of this standard
36、is maintained. A product whose features, characteristics, components, materials, or systems conict with specic requirements or provisions of this standard shall not be judged to comply with this standard. Where appropriate, revision of requirements shall be proposed and adopted in conformance with t
37、he methods employed for development, revision, and implementation of this standard. 2 Components 2.1 A component of a product covered by this standard shall comply with the requirements for that component. See Appendix A for a list of standards covering components generally used in the products cove
38、red by this standard. 2.2 A component is not required to comply with a specic requirement that: a) Involves a feature or characteristic not required in the application of the component in the product covered by this standard, or b) Is superseded by a requirement in this standard. APRIL 30, 2012 FUSE
39、D POWER-CIRCUIT DEVICES - UL 977 6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 3 Units of measurement 3.1 If a value for measurement is followed by a value in other units, the use or recognition of either value can be expected to provide
40、equivalent results in the application of such requirements. 4 References 4.1 Any undated reference to a code or standard appearing in the requirements of this standard shall be interpreted as referring to the latest edition of that code or standard. CONSTRUCTION 5 General 5.1 A fused power-circuit d
41、evice shall employ materials throughout that are acceptable for the particular application, and shall be made and nished with the degree of uniformity and grade of workmanship practicable in a well-equipped factory. 5.2 The construction of a fused power-circuit device shall be such as to provide amp
42、le strength and rigidity. 5.3 All parts of a fused power-circuit device shall be properly assembled in place when shipped from the factory, except as noted in 5.4, 5.6, 5.7, 5.8, and 5.9. 5.4 If a fused power-circuit device is acceptable for use without a neutral assembly as well as with such assemb
43、ly, the neutral assembly need not be shipped from the factory with the switching unit provided that: a) The neutral assembly is shipped from the factory completely assembled with the necessary barriers and all other accessories that are required for its installation and use; and b) The neutral assem
44、bly and switch are marked in accordance with 50.12. 5.5 With reference to 5.4, hardware for mounting the neutral assembly must be furnished with that assembly but need not be assembled in place. 5.6 External operating handles need not be assembled in place but in place of such assembly, they are to
45、be packaged and shipped with the switching unit. 5.7 When a fused power-circuit device without enclosure is shipped for assembly in a switchboard or similar equipment, the load fuse terminal assembly need not be mounted in place when all the following conditions are met: a) All poles of the load fus
46、e terminal assembly are secured to a common base that can be installed as a single unit by a simple assembly operation; b) Assembly instructions and markings are provided; c) The construction is such that alignment of fuse mounts will be assured; d) Barriers or stops intended to prevent over-sized f
47、using will continue to be effective; and e) The load fuse terminal assembly is packaged and shipped with the switching unit. APRIL 30, 2012 FUSED POWER-CIRCUIT DEVICES - UL 977 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 5.8 If the prop
48、er operation or installation of an open type fused power-circuit device is dependent upon an insulating barrier, liner, shield or similar member being mounted on the device or elsewhere, the insulating barrier shall be provided with the device and a marking as specied in 50.29 shall be provided. 5.9
49、 If a fused power-circuit device is intended for use with or without an accessory assembly, the assembly need not be shipped from the factory with the fused power-circuit device provided that: a) The fused power-circuit device is acceptable for use with or without the accessory. b) Each accessory is acceptable for the intended use. c) Installation instructions for the proper installation operation, and necessary adjustments are provided: 1) With the accessory; 2) With the fused power-circuit device; or 3) The accessory i
