1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 508C Power Conversion Equipment STANDARD FOR SAFETYUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MATERIAL NOT AUTHO
2、RIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Power Conversion Equipment, UL 508C Fourth Edition, Dated May 16, 2016 Summary of Topics This new edition was issued to incorporate the following changes: Modication of Short-Circuit Testing Requirem
3、ents Clarication of Control Circuit Transformer Protection Requirements Revision of Ratings for Capacitors in AC Circuits Revision of Marking and Instruction Requirements to Use Appropriate Signal Words Revision of Frequency Requirements for Dielectric Voltage Withstand Testing Revision of Breakdown
4、 of Components Testing in Secondary Circuits Revision of Table 63.1 to Include Marking Requirements in 56.6 and 56.7 Slash and Straight Voltage Ratings for Drives with a 3-Phase Input Revision to the conductor temperature limit during the Temperature Test, Section 40 Revision of 56.7 to align with r
5、equirements in NFPA 70 Revisions to Section 68, Plenum Rated Drives The new and revised requirements are substantially in accordance with Proposal(s) on this subject dated September 9, 2011 and November 1, 2013. All rights reserved. No part of this publication may be reproduced, stored in a retrieva
6、l 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, including but not limited to, the implied warranties of merchanta
7、bility 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, or any other damages arising out of the use of or the inability to use this Standard, even if UL or an authoriz
8、ed 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 form of the claim. Users of the electronic versions of ULs Standards for Safety agree to defend, indemnify, and hold
9、 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 purchaser is storing an electronic Standard on the purchasers computer system. MAY 16, 2016 UL 508C tr1UL COPYRIGHTED MA
10、TERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL MAY 16, 2016 UL 508C tr2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL MAY 16, 2016 1 UL 508C Standard for Power Conversion Equip
11、ment First Edition December, 1993 Second Edition November, 1996 Third Edition May, 2002 Fourth Edition May 16, 2016 This ANSI/UL Standard for Safety consists of the Fourth Edition. The most recent designation of ANSI/UL 508C as an American National Standard (ANSI) occurred on May 16, 2016. ANSI appr
12、oval for a standard does not include the Cover Page, Transmittal Pages and Title Page. 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 (C
13、SDS) 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 20
14、16 UNDERWRITERS LABORATORIES INC. ANSI/UL 508C-2016UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL MAY 16, 2016 POWER CONVERSION EQUIPMENT - UL 508C 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DIS
15、TRIBUTION WITHOUT PERMISSION FROM UL CONTENTS INTRODUCTION 1 Scope .7 2 Glossary .7 3 Units of Measurement 10 4 Components 10 5 Undated References .10 ENCLOSURE CONSTRUCTION 6 Frames and Enclosure .10 6.1 General 10 6.2 Cast metal 11 6.3 Sheet metal 11 6.4 Doors and covers .15 6.5 Polymeric .19 6.6
16、Bonding 20 6.7 Resistance measurement .22 6.8 Openings in enclosure .22 6.9 Accessibility of live parts .22 6.10 Ventilating openings 25 6.11 Forced ventilation 26 6.12 Observation windows .26 6.13 Wire bending space 26 ENVIRONMENTAL RATING RELATED ENCLOSURE CONSTRUCTION 7 General .27 8 Protection A
17、gainst Corrosion 27 ENVIRONMENTAL RATING RELATED ENCLOSURE PERFORMANCE 9 General .28 NON-ENVIRONMENTAL RATING RELATED ENCLOSURE PERFORMANCE 10 General 30 11 Securement of Snap-On Cover Test 30 INSTRUCTIONS AND MARKINGS PERTAINING TO ENCLOSURES 12 Permanence of Marking .30 13 Details .31 DEVICE CONST
18、RUCTION 14 General 31 15 Protection Against Corrosion .31 16 Provisions for Mounting 31 17 Insulating Material 32 MAY 16, 2016 POWER CONVERSION EQUIPMENT - UL 508C 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 18 Means for Switching 34 19
19、 Live Parts 35 20 Drive Protection 35 20.1 General .35 20.2 Control circuit wiring 36 20.3 Control circuit transformer .38 20.4 Control circuit wiring and transformer combination 39 21 Capacitors .40 22 Fuseholders 40 23 Internal Wiring 41 23.1 General .41 23.2 Routing .41 23.3 Flexing 41 23.4 Color
20、 coding .42 23.5 Splices and connections 42 23.6 Splice insulation 43 24 External Interconnections 43 24.1 Open equipment .43 24.2 Enclosed equipment 43 24.3 Interconnecting cords and cables 43 25 Transformers .44 26 Blower Motors 44 27 Supply Connections .45 27.1 General .45 27.2 Permanently connec
21、ted equipment .45 27.3 Tapped holes for conduit 45 27.4 Knockouts .46 27.5 Wiring terminals and leads 46 27.6 Cord-connected equipment 49 28 Cord-Connected Programming and Diagnostic Units .50 29 Risk of Electric Shock .51 30 Risk of Fire 51 31 Lithium Battery Circuits 52 32 Isolated Secondary Circu
22、its 52 32.1 General .52 32.2 Class 2 circuits .55 32.3 Limited voltage/current circuits .55 32.4 Limited voltage circuits 56 32.5 Isolated power supply circuits 56 32.6 Limited energy circuits 57 32.7 Limiting impedance circuits 57 33 Limited Voltage Circuit Overcurrent Protection .59 33.1 General .
23、59 33.2 Primary overcurrent protection .59 33.3 Secondary overcurrent protection 60 34 Separation of Circuits .60 35 Isolation Devices .61 36 Spacings 62 36.1 General .62 36.2 Spacings other than at eld-wiring terminals 65 36.3 Spacings at eld-wiring terminals for pollution degree 2 environments 67
24、36.4 Spacings for drives having general ratings for pollution degree 2 environments 67 36.5 Spacings for drives having limited ratings .68 MAY 16, 2016 POWER CONVERSION EQUIPMENT - UL 508C 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 36.
25、6 Spacings for drives having other ratings 68 36.7 Spacings for products with known and controlled transient voltages 68 36.8 Spacings for drives used in pollution degree 2 environments 69 36.9 Spacings for drives evaluated in accordance with UL 840 .69 36.10 Testing in lieu of spacings 70 36.11 Ins
26、ulating material used as a barrier in lieu of spacings 71 36.12 Clamped insulating joints in lieu of spacings .73 36.13 Spacings between live parts and conduit openings 75 37 Grounding .75 38 Accessories 76 DEVICE PERFORMANCE 39 General 76 40 Temperature Test .78 41 Abnormal Operation Tests .83 41.1
27、 General .83 41.2 Contactor overload .86 41.3 Single phasing .86 41.4 Inoperative blower motor 86 41.5 Clogged lter 86 41.6 Current limiting control .87 42 Full-Load Motor-Running Current Tables 87 43 Solid State Motor Overload Protection Test 88 43.1 General requirements .88 43.2 Test set-up 89 43.
28、3 Thermal memory retention test (shutdown) 89 43.4 Thermal memory retention test (loss of power) .90 43.5 Speed sensitivity test .90 44 Dielectric Voltage-Withstand Test .90 44.1 General .90 44.2 Clamped joints .91 45 Short Circuit Test Standard Fault Currents .91 45.1 General .91 45.2 Test circuit
29、current/voltage .94 45.3 Input/output wiring connection .97 45.4 Ground fuse .98 45.5 Enclosures 98 45.6 Mounting 98 45.7 Openings 99 45.8 Branch circuit short circuit protection 99 46 Group Installation (Optional) 101 46.1 General 101 46.2 Sample selection 102 46.3 Short circuit test group installa
30、tion for standard fault currents .103 46.4 Short circuit test group installation for high fault currents .104 47 Calibration of Short Circuit Test Circuits. .104 47.1 10,000 amperes or less 104 47.2 More than 10,000 amperes .105 48 Short Circuit Test High Fault Currents 108 49 Transient-Voltage-Surg
31、e Suppression Test .111 50 Accelerated Aging Test .112 51 Breakdown of Components Test 113 MAY 16, 2016 POWER CONVERSION EQUIPMENT - UL 508C 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 52 Breakdown of Components Test Group Installation
32、for Standard Fault Currents .114 53 Breakdown of Components Test Group Installation for High Fault Currents .115 54 Printed Wiring Board Abnormal Operation Test 115 55 Secondary Circuits Test 116 55.1 General 116 55.2 Limited voltage/current secondary test .117 55.3 Limited energy secondary test 117
33、 55.4 Isolated power supply capacity test 117 55.5 Limited voltage secondary test .117 55.6 Limiting impedance test 118 56 Strain Relief Test 119 57 Push-Back Relief Test 119 58 Leakage Current Test 120 59 Rating 122 DEVICE MARKING 60 General 123 61 Overload, Over-Current, and Over-Speed Protection
34、.124 62 Branch Circuit Short Circuit Protection .125 63 Branch Circuit Short Circuit Protection for Group Installation 126 64 Control Circuit Protection 127 65 Class 2 Circuit Markings .127 66 Wiring Terminal Markings 128 67 Cautionary Markings .130 68 Instructions and Markings Pertaining to Accesso
35、ries .132 69 Marking Location 132 MANUFACTURING AND PRODUCTION LINE TEST 70 Circuit Functionality Evaluation 136 71 Production-Line Dielectric Voltage-Withstand Test .136 72 Production-Line Grounding-Continuity Test .138 73 Production-Line Polarization-Continuity Test Cord and Plug Connected Equipme
36、nt 138 COOLING SYSTEMS 74 General 138 75 Construction 139 76 Performance 140 76.1 Loss of cooling medium circulation test 140 76.2 Hydrostatic pressure test 141 77 Plenum Rated Drives 141 APPENDIX A Standards for ComponentsA1 MAY 16, 2016 POWER CONVERSION EQUIPMENT - UL 508C 6UL COPYRIGHTED MATERIAL
37、 NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL INTRODUCTION 1 Scope 1.1 These requirements cover open or enclosed equipment that supplies power to control a motor or motors operating at a frequency or voltage different than that of the input supply. These require
38、ments also cover power-supply modules, input/output modules, Silicon Controlled Rectier (SCR) or Transistor output modules, dynamic braking units, and input/output accessory kits for use with power conversion equipment. 1.2 This equipment is for use in ordinary locations in accordance with Articles
39、430 and 440 of the National Electrical Code, NFPA 70. 1.3 These requirements cover devices rated 1500 volts or less. 1.4 Equipment intended for use in hazardous locations as dened by the National Electrical Code, NFPA 70, shall be evaluated to the Standard for Explosion-Proof and Dust-Ignition-Proof
40、 Electrical Equipment for Use in Hazardous (Classied) Locations, UL 1203. 2 Glossary 2.1 For the purpose of this standard, the following denitions apply. 2.2 AMBIENT TEMPERATURE The temperature of the room or chamber in which the equipment under test is located. 2.3 CONTROL CIRCUIT A circuit that ca
41、rries the electric signals directing the performance of a controller, and does not carry the main power circuit (see IEEE Standards Dictionary of Electrical and Electronic Terms). A control circuit is mostly limited to 15 amperes. 2.4 DRIVE SERIES A number of drives produced as a related group, usin
42、g similar design throughout the group. Examples of grouping include but are not limited to specic ratings, application or function. 2.5 ENCLOSURE, ENCLOSED DEVICE Industrial control equipment provided with a suitably rated enclosure. (See the Standard for Enclosures for Electrical Equipment, UL 50 f
43、or details.) 2.6 ENCLOSURE, OPEN DEVICE Industrial control equipment with an incomplete or partial enclosure. 2.7 GROUP INSTALLATION A motor branch circuit for two or more motors, or one or more motors with other loads and protected by a circuit breaker or a single set of fuses. 2.8 INSULATED LIVE P
44、ART An electrically live part that is provided with complete protection against electric shock and does not rely upon other parts for insulation. 2.9 POLLUTION DEGREE1N opollution or only dry, nonconductive pollution occurs. The pollution has no inuence. Pollution degree 1 is obtainable by the encap
45、sulation or hermetic sealing of the product. Typical constructions that meet this requirement are: a) The use of conformal coating on printed wiring board foil traces that complies with the requirements for Conformal Coatings in the Standard for Polymeric Materials Use in Electrical Equipment Evalua
46、tions, UL 746C; b) The use of any potting material or encapsulation, such as epoxy; MAY 16, 2016 POWER CONVERSION EQUIPMENT - UL 508C 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL c) The use of silicone rubber at a thickness of at least 1
47、/32 inch (0.79 mm); d) The use of a case or enclosure that is hermetically sealed against the entrance of an external atmosphere by means of fusion such as from soldering, brazing, welding, or the fusion of glass to metal. 2.10 POLLUTION DEGREE 2 Normally, only nonconductive pollution occurs; howeve
48、r, temporary conductivity is expected. Pollution degree 2 is obtainable by reducing possibilities of conductive pollution and reducing possibilities of condensation or high humidity at the creepage distances. a) Typical constructions that reduce the possibility of conductive pollution are: 1) The us
49、e of an un-ventilated enclosure; 2) The use of a ltered ventilated enclosure when the ventilation is fan forced that is, ventilation is accomplished by one or more blowers within the enclosure that provide a positive intake and exhaust; or 3) The use of an un-ltered ventilated enclosure when the ventilation is not fan forced. b) Typical constructions that reduce the effects of condensation or high humidity are: 1) The use of a ventilated enclosure; 2) The continuo
