1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 873 Temperature-Indicating and -Regulating EquipmentUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MATERIAL NOT AUTH
2、ORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Temperature-Indicating and -Regulating Equipment, UL 873 Twelfth Edition, Dated November 16, 2007 Summary of Topics The revision dated February 6, 2015 is being issued to adopt the following proposa
3、l: 1. Revising the multiple disconnect caution marking text height requirement in 74.2. Text that has been changed in any manner or impacted by ULs electronic publishing system is marked with a vertical line in the margin. Changes in requirements are marked with a vertical line in the margin and are
4、 followed by an effective date note indicating the date of publication or the date on which the changed requirement becomes effective. The new requirements are substantially in accordance with Proposal(s) on this subject dated November 5, 2014. All rights reserved. No part of this publication may be
5、 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, including but not limited to, th
6、e 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, or any other damages arising out of the use of or the inability to use this St
7、andard, 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 form of the claim. Users of the electronic versions of ULs Standards for Safety agr
8、ee 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 purchaser is storing an electronic Standard on the purchasers computer system. The requ
9、irements 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 revised and that have a future e
10、ffective date are located after the Standard, and are preceded by a SUPERSEDED REQUIREMENTS notice. FEBRUARY 6, 2015 UL 873 tr1UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL FEBRUARY 6, 2015 UL 873 tr2 No Text on This PageUL COPYRIGHTED MAT
11、ERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL NOVEMBER 16, 2007 (Title Page Reprinted: February 6, 2015) 1 UL 873 Standard for Temperature-Indicating and -Regulating Equipment First Edition August, 1942 Second Edition March, 1945 Third Edition January, 1947
12、 Fourth Edition June, 1953 Fifth Edition December, 1956 Sixth Edition December, 1958 Seventh Edition May, 1970 Eighth Edition September, 1972 Ninth Edition May, 1979 Tenth Edition September, 1988 Eleventh Edition December, 1994 Twelfth Edition November 16, 2007 This UL Standard for Safety consists o
13、f the Twelfth Edition including revisions through February 6, 2015. The Department of Defense (DoD) has adopted UL 873 on January 17, 1992. The publication of revised pages or a new edition of this Standard will not invalidate the DoD adoption. Comments or proposals for revisions on any part of the
14、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 altered in any w
15、ay. All of ULs Standards and all copyrights, ownerships, and rights regarding those Standards shall remain the sole and exclusive property of UL. COPYRIGHT 2015 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JA
16、NUARY 6, 2012 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CONTENTS INTRODUCTION 1 Scope .9 2 Glossary 11 3 Units of Measurement 12 4 Components 12 5 Referenc
17、es 12 CONSTRUCTION 5A Components .12 5A.1 General .12 5A.2 Attachment plugs, receptacles, connectors, and terminals .12B 5A.3 Batteries .12C 5A.4 Electrical boxes and raceways .12C 5A.5 Capacitors, lters and surge protective devices .12C 5A.6 Thermistors and thermal links 12F 5A.7 Cords and cables .
18、12F 5A.8 Gaskets and seals 12F 5A.9 Ground-fault, arc-fault, and leakage current detectors/interrupters 12G 5A.10 Heaters and heating elements 12G 5A.11 Insulation systems .12G 5A.12 Light sources and associated components 12H 5A.13 Marking and labeling systems .12H 5A.14 Overcurrent protection 12I
19、5A.15 Power supplies .12I 5A.16 Printed wiring boards .12J 5A.17 Power switching semiconductors, optical isolators, and electronic components . . . .12J 5A.18 Supplemental insulation, insulating bushings, and assembly aids 12L 5A.19 Transformers 12L 5A.20 Valves (electrically operated) and solenoids
20、 12M 6 General .12M 7 Frame and Enclosure 13 7.1 General 13 7.2 Accessibility of live parts .13 7.3 Covers .15 7.4 Transformers .16 7.5 Cast metal 16 7.6 Sheet metal 17 7.7 Polymeric .19 7.8 Windows .20 7.9 Room thermostats .20 7.10 Openings 21 7.11 Screens and expanded metal 24 7.12 Wiring openings
21、 24 7.13 Raintight and rainproof enclosures .26 8 Mounting 26 9 Parts Containing Liquid Metal .27 10 Adjustment Stop 27 11 Operating Mechanism .28 JANUARY 6, 2012 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 2AUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTI
22、ON WITHOUT PERMISSION FROM UL 12 Reset Mechanism Limiting Control 30 13 Means for Calibration .31 14 Protection Against Corrosion .32 15 Insulating Material 34 16 Supply Connections .34A 16.1 General 34A 16.2 Equipment permanently connected electrically 34A 16.3 Cord and plug connected portable equi
23、pment 39 16.4 Stationary equipment .39 17 Current-Carrying Parts .40A 18 Switches .40A 19 Internal Wiring 40B 20 Low-Voltage External Wiring Requirements 42 21 Grounding .43 21.1 General .43 21.2 Grounding means 44 21.3 Equipment permanently connected electrically .45 21.4 Terminals and leads 45 22
24、Bonding of Internal Parts 48 22.1 General .48 22.2 Construction and connection .49 23 Protection of Users and Service Personnel 51 23.1 General .51 23.2 Mechanical servicing 52 23.3 Electrical servicing 53 24 Protection Against Injury to Persons 54 24.1 Scope 54 24.2 Sharp corners and edges .54 24.3
25、 Moving parts .54 24.4 Temperature .55 24.5 Mounting devices 55 24.6 Strength of parts .55 25 Capacitors .56 26 Fuseholders 57 27 Receptacles 57 28 Protection of Control-Circuits .57 28.1 Conductors 57 28.2 Transformers 59 29 Short-Circuit, Ground-Fault, Overload, and Thermal Protection .60 30 Mercu
26、ry-Tube Switches 60A 31 Coil Windings .60A 32 Spacings .60A 32.1 General 60A 32.2 Line-voltage circuits 61 32.3 Magnet coil windings .65 32.4 Low-voltage circuits .65 32.5 Isolated limited secondary circuits 66 33 Alternate Spacings Clearances and Creepage Distances 67 34 Wiring Space .68 35 Separat
27、ion of Circuits .69 35.1 Separation between different internal wiring circuits (factory-installed conductors) 69 35.2 Separation between different eld wiring circuits (eld-installed conductors) .69 35.3 Separation between eld wiring circuits (eld-installed conductors) and internal wiring JANUARY 6,
28、2012 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 2BUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL circuits (factory-installed conductors) 70 35.4 Segregation methods .72 35.5 Separation methods 72 36 Class 2 Power Sources and
29、Circuits 73 36.1 General .73 36.2 Interconnections .73 36.3 Circuits 73 36.4 Transformers 74 36.5 Power limiting components 74 36.6 Overcurrent protection components .75 37 Barriers 75 PERFORMANCE 38 General 76 38.1 Samples 76 38.2 Electric heat thermostat .77 38.3 Controller 77 38.4 Baseboard heate
30、r controls 78 38.5 Relays 78 38.6 Electric range controls 82 38.7 Auxiliary electric range controls 84 38.8 Conditioning at elevated temperature household range control switch body 84 38.9 Temperature-limiting controls for electric ranges .85 38.10 Ice and Snow-Melting Equipment Controls .86 39 Powe
31、r Input 86 40 Temperature Test .86 41 Leakage Current Test .90 42 Leakage Current Following Humidity Conditioning Test 92 43 Operation Test .93 44 Calibration-Verication Test 93 45 Overload Test 95 46 Endurance Test .101 47 Dielectric Voltage-Withstand Test 104 47.1 General 104 47.2 Induced potentia
32、l 105 47.3 Induced potential repeated .106 47A Abnormal Operation Test 106 47A.1 General .106 47A.2 Abnormal Switching Test .106 48 Volt-Ampere Capacity Test 106A 49 Burnout Test .106B 50 Short Circuit Test 107 50.1 Mercury-tube switch .107 50.2 Conductor 108 50.3 Equipment for motor control 109 51
33、Parts Containing Liquid Metal Test .109 52 Two-Step Operation Surface-Unit Controls Test .109 52.1 General 109 52.2 Push- and pull-and-turn controls 110 52.3 Other types of controls .111 53 Strain-Relief Test 111 54 Accelerated Aging Tests on Gaskets, Sealing Compounds, and Adhesives .111 AUGUST 15,
34、 2013 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 2CUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 55 Metallic Coating Thickness Test .113 56 Rain Test .115 57 Time-Calibration Verication Test 118 AUGUST 15, 2013 TEMPERATURE-I
35、NDICATING AND -REGULATING EQUIPMENT - UL 873 2DUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL AUGUST 15, 2013 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 3 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER
36、 REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 57.1 General 118 57.2 Bimetal-heater design 118 57.3 Initial time-calibration-verication Test I 118 57.4 Initial time-calibration-verication Test II 119 57.5 Endurance .119 57.6 Time-verication and dielectric voltage-withstand tests after endu
37、rance 119 57.7 Other designs 120 58 Snap-On Covers Test 120 59 Bonding Conductor Tests .121 59.1 Overcurrent 121 59.2 Resistance .121 60 Permanence of Marking Test 122 60.1 General 122 60.2 Oven-aging .122 60.3 Immersion 123 60.4 Standard-atmosphere 123 60.5 Unusual condition exposure 123 60.6 Humid
38、ity .123 61 Strength of Adjustment Stop Test 123 62 Polymeric Materials Tests 125 62.1 General 125 62.2 Conduit connections .125 62.3 Knockouts 127 63 Class 2 Power Sources and Circuit Tests .127 63.1 General 127 63.2 Ambient air temperature .132 63.3 Open-circuit secondary voltage .133 63.4 Maximum
39、 current of inherently limited power source .135 63.5 Maximum current of not inherently limited power source .142 63.6 Maximum power of not inherently limited power source 142 63.7 Calibration of overcurrent-protective devices 142 63.8 Rated secondary output 143 63.9 Rated output heating 143 63.10 D
40、ielectric voltage withstand 143 63.11 Component breakdown .144 63.12 Overload heating .144 63.13 Repeat dielectric voltage withstand .146 63.14 Overload of overcurrent- or overtemperature-protective devices 146 63.15 Endurance of automatic-reset overtemperature-protective devices .146 64 Isolated-Li
41、mited Secondary and Non-Class 2 Circuits Tests .147 MANUFACTURING AND PRODUCTION TESTS 65 Details .147 65.1 General 147 65.2 Marked-off position 148 66 Grounding Continuity .148 RATING 67 General 148 68 Class 2 Power Sources and Circuits .150 AUGUST 15, 2013 TEMPERATURE-INDICATING AND -REGULATING EQ
42、UIPMENT - UL 873 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL MARKING 69 General 150 70 Wiring 153 71 Calibration Setting .154 72 Elevated Air Temperature .155 73 Location 156 74 Cautionary Markings .156 75 Class 2 Power Sources and Circ
43、uits .157 76 Instructions .158 SPECIAL-PURPOSE DEVICES 77 Scope 158 78 Fan/Heat Sequencers 158 78.1 Scope .158 78.2 General 159 78.3 Performance 160 78.4 Mechanical and production tests 162 78.5 Rating .162 78.6 Marking 162 79 Fluorescent-Lamp-Ballast Protectors .163 JANUARY 6, 2012 TEMPERATURE-INDI
44、CATING AND -REGULATING EQUIPMENT - UL 873 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JANUARY 6, 2012 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 6 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REP
45、RODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 79.1 Scope .163 79.2 General 163 79.3 Construction 163 79.4 Performance 163 79.5 Manufacturing and production tests .165 79.6 Marking 165 80 Control-Circuit Temperature-Limiting Devices for Temperature Protection of Enclosures of Motors and Genera
46、tors for Use in Hazardous Location .165 80.1 Scope .165 80.2 General 166 80.3 Construction 166 80.4 Performance 166 80.5 Manufacturing and production tests .167 80.6 Rating .167 80.7 Marking 168 81 Single-Operation Devices .168 81.1 Scope .168 81.2 General 168 81.3 Operation mechanism .168 81.4 Cons
47、truction 169 81.5 Performance 169 81.6 Manufacturers inspection and test program 170 81.7 Ratings 171 81.8 Marking 171 82 Thermal Protective Devices for Lighting Fixtures 171 82.1 Scope .171 82.2 Enclosures .171 82.3 Accessibility 172 82.4 Open hole 173 82.5 Insulating materials 173 82.6 Wiring conn
48、ections 173 82.7 Mounting hardware 174 82.8 Spacings .174 82.9 Performance 174 82.10 Manufacturing and production-line tests .183 82.11 Ratings .184 82.12 Markings 184 83 Controllers for Solar-Energy Systems 184 83.1 Scope .184 83.2 Supply connections 185 83.3 Marking 185 83.4 Instructions .186 84 T
49、emperature-Regulating Thermostats for Household Drip-Type Coffee Makers 186 84.1 Scope .186 84.2 Glossary .186 84.3 Construction 187 84.4 Performance 187 84.5 Ratings 188 84.6 Markings .188 NOVEMBER 16, 2007 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL JANUARY 6, 2012 TEMPERATURE-INDICATING AND -REGULATING EQUIPMENT - UL 873 8UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR
