1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 921 Commercial Dishwashers STANDARD FOR SAFETYUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MATERIAL NOT AUTHORIZED
2、 FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Commercial Dishwashers, UL 921 Seventh Edition, Dated March 23, 2016 Summary of Topics This revision includes: 4.7, Power-supply connections and 4.13, Equipment grounding and bonding Addition And Revision
3、 Of Requirements To Relocate Component Standard References From Appendix A Into The Body Of The Standard As Component Requirements Requirements for the Evaluation of Electronic Circuits in Commercial Dishwashers Text that has been changed in any manner or impacted by ULs electronic publishing system
4、 is marked with a vertical line in the margin. In the revisions dated September 20, 2017 Appendix A have been intentionally deleted from the Standard due to the deletion or relocation of text. The revised requirements are substantially in accordance with Proposal(s) on this subject dated December 16
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9、electronic Standard on the purchasers computer system. SEPTEMBER 20, 2017 UL 921 tr1UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL SEPTEMBER 20, 2017 UL 921 tr2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUC
10、TION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CSA Group CSA C22.2 No. 16816 Second Edition CSA America ANSI Z83.212016 Second Edition Underwriters Laboratories Inc. UL 921 Seventh Edition Commercial Dishwashers March 23, 2016 (Title Page Reprinted: September 20, 2017) ANSI/UL 921-2017 Approved byU
11、L COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL Commitment for Amendments This standard is issued jointly by the the Canadian Standards Association (operating as “CSA Group”), and Underwriters Laboratories Inc. (UL). Comments or proposals for
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21、aspx or call toll-free 1-888-853-3503.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CONTENTS PREFACE 6 1 Scope .8 2 General 8 2.1 Components .8 2.2 Units of measurement 10 2.3 Reference publications .10 2.4 General requirements 13 3 Deniti
22、ons 13 4 Construction Requirements Applicable To All Dishwashers 16 4.1 General 16 4.2 Field-attached accessories .19 4.3 Doors and covers .20 4.4 Accessibility of current-carrying parts 20 4.5 Corrosion protection .22 4.6 Mechanical assembly 22 4.7 Power-supply connections 23 4.8 Current-carrying p
23、arts 26 4.9 Internal wiring .27 4.10 Separation of circuits 28A 4.11 Insulating materials 28B 4.12 Thermal insulation .30 4.13 Equipment grounding .31 4.14 Lampholders 32 4.15 Receptacles 32A 4.16 Capacitors 33 4.17 Overcurrent- or overload-protective devices .34 4.18 Overcurrent and overload protec
24、tion for motors 34 4.19 Overcurrent protection for transformers .35 4.20 Overcurrent protection for conductors .36 4.21 Switches .37 4.22 Controls .37 4.23 Spacings .40B 4.23A Alternative spacings-clearances and creepage distances .40C 4.24 Seals and gaskets 41 4.25 Moisture condensation .41 5 Const
25、ruction Requirements Unique To Gas-Fired Dishwashers 41 5.1 General 41 5.2 Manually-operated gas valves .43 5.3 Automatic valves and safety shutoff valves .44 5.4 Gas pressure regulators 44 5.5 Ignition systems .44 5.6 Pilot-gas lters 46 5.7 Gas supply line .46 5.8 Semi-rigid tubing 47 6 Reduction O
26、f Risk Of Injury To Persons Requirements Applicable To All Dishwashers .47 6.1 Enclosure and guards 47 6.2 Automatic restarting of motor .48 6.3 Parts subject to air or steam pressure .48 6.4 Pressure-relief devices .49 SEPTEMBER 20, 2017 CSA C22.2 NO. 16816 ANSI Z83.212016 UL 921 3UL COPYRIGHTED MA
27、TERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 7 Performance Requirements Applicable To All Dishwashers .49 7.1 General 49 7.2 Electrical input test 50 7.3 Starting current test 50 7.4 Normal temperature test 51 7.5 Temperature measuring equipment and enclo
28、sure setup .52 7.6 Dielectric voltage-withstand test .54 7.7 Flexing test .55 7.8 Insulation resistance following humidity conditioning test .56 7.9 Water exposure tests 56 7.10 Flooding of current-carrying parts test .58 7.11 Hydrostatic pressure test 59 7.12 Reservoir overow test 59 7.13 Liquid co
29、ntainers, seals, and diaphragms tests .60 7.14 Limited short-circuit test (motor protection) 60 7.15 Abnormal operation test .61 7.16 Blocked plunger test 61 7.17 Overvoltage for electrolytic capacitors test 62 7.18 Overload on switches test .62 7.19 Transformer overcurrent protection test .63 7.20
30、Transformer burnout test 63 7.21 Door interlock endurance test 64 7.22 Loading door/drawer moment load test 64 7.23 Strain relief test 64 7.24 Push-back relief test 64 8 Performance Requirements Unique To Electrically-Heated Dishwashers 64 8.1 Automatic temperature control tests .64 9 Performance Re
31、quirements Unique To Gas-Fired Dishwashers 65 9.1 General 65 9.2 Test gases .67 9.3 Test pressures and burner adjustments test 67 9.4 Normal operation combustion test .67 9.5 Undervoltage combustion test .68 9.6 Combustion air failure test 68 9.7 Burner operating characteristics test .69 9.8 Pilot i
32、gnition systems test .70 9.9 Direct ignition systems tests 75 9.10 Flue gas temperature for draft hood appliances test 77 10 Manufacturing And Production Tests Unique To Electrically-Heated Dishwashers .77 10.1 Production line dielectric voltage-withstand test 77 10.2 Production line grounding conti
33、nuity test 79 11 Manufacturing And Production Tests Unique To Gas-Fired Dishwashers 79 12 Rating Requirements Applicable To All Dishwashers 79 13 Marking Requirements Applicable To All Dishwashers .80 14 Marking Requirements Unique To Electrically-Heated Dishwashers .80 15 Marking Requirements Uniqu
34、e To Gas-Fired Dishwashers .83 16 Installation Instructions Applicable to All Dishwashers .84 17 Installation Instruction Requirements Unique to Electrically-Heated Dishwashers .84 18 Installation Instruction Requirements Unique To Gas-Fired Dishwashers 84 SEPTEMBER 20, 2017 CSA C22.2 NO. 16816 ANSI
35、 Z83.212016 UL 921 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL SUPPLEMENT SA - COMMERCIAL DISHWASHERS SELF-CONTAINED CONDENSING SYSTEMS INTRODUCTION SA1 Scope 101 CONSTRUCTION SA2 Condenser Tubing and Fittings 101 SA3 Pressure Relief 10
36、2 SA3.1 General 102 PERFORMANCE SA4 Heat Load Calculation Test (United States Only) .102 SA5 Strength Tests Pressure-Containing Components 104 MARKINGS SA6 General (United States Only) 105 SUPPLEMENT SB - EVALUATION OF ELECTRONIC CIRCUITS(Normative) INTRODUCTION SB1 Scope 107 SB2 General .107 SB3 Gl
37、ossary 107 CONSTRUCTION SB4 Components .109 SB4.1 Capacitors 109 SB4.2 Isolation devices .109 SB4.3 Printed wiring boards .110 SB4.4 Switch Mode Power Supplies .110 SB4.5 Temperature sensing, thermistor devices .110 SB4.6 Transformers 111 SB5 Identication of Safety Critical Circuit Functions 111 SB5
38、.1 General 111 SB5.2 Protective Electronic Circuits (PEC) 111 SB5.3 Operating circuits that mitigate a dangerous malfunction of the appliance 112 SB6 Evaluation of the Different Types of Electronic Circuits .112 SB6.1 All types of circuits .112 SB7 Circuits that provide Safety Critical Functions 112
39、 PERFORMANCE SB8 General Conditions for the Tests .113 SEPTEMBER 20, 2017 CSA C22.2 NO. 16816 ANSI Z83.212016 UL 921 4AUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL SB8.1 Details .113 SB8.2 Intentionally weak parts 113 SB8.3 Test results d
40、etermined by overcurrent protection operation 114 SB9 Determination of Low-Power Circuits .114 SB10 Abnormal Operation and Fault Tests 115 SB10.1 General .115 SB10.2 Determination of fault conditions 116 SB10.3 Low-power circuit re tests 117 SB10.4 Transformer overload test .117 SB10.5 Switch mode p
41、ower supply overload test 118 SB11 Programmable Component Reduced Supply Voltage Test .118 SB12 Electromagnetic Compatibility (EMC) Requirements - Immunity .118 MANUFACTURING AND PRODUCTION LINE TESTING SB13 General 120 APPENDIX A Standards for Components Appendix A deleted APPENDIX B Marking French
42、 Translations SEPTEMBER 20, 2017 CSA C22.2 NO. 16816 ANSI Z83.212016 UL 921 4BUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL SEPTEMBER 20, 2017 CSA C22.2 NO. 16816 ANSI Z83.212016 UL 921 5 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUT
43、HORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL PREFACE This is the common CSA Group, and UL standard for Commercial Dishwashers. It is the Second edition of CSA C22.2 No. 168, the Second edition of ANSI/ CSA Z83.21, and the Seventh edition of UL 921. This edition of CSA
44、C22.2 No. 168, ANSI/ CSA Z83.21, supersedes the previous edition published in 2006. This edition of UL 921 supersedes the previous edition(s) published on January 31, 2006. This harmonized standard was prepared by CSA Group and Underwriters Laboratories Inc. (UL). The efforts and support of the Z83/
45、CSA Joint Technical Subcommittee on Standards for Gas Food Service Equipment, and representatives of the commercial dishwasher industry in Canada and the United Stated for developing this harmonized standard are gratefully acknowledged. Major changes in this edition are the addition of Supplement SA
46、 COMMERCIAL DISHWASHERS SELF-CONTAINED CONDENSING SYSTEMS, updating the reference documents and reformatting to latest editorial guidelines. This standard is considered suitable for use for conformity assessment within the stated scope of the standard. This standard was reviewed by the Z83/CSA Joint
47、 Technical Subcommittee on Standards for Gas Food Service Equipment under the jurisdiction of the Technical Committee on Performance and Installation of Gas Burning Appliances and Related Accessories and the Strategic Steering Committee on Standards for Gas Burning Appliances and Related Accessories
48、, and has been formally approved by the Z21/83 and CSA Technical Committees, American National Standards Institute, and the Interprovincial Gas Advisory Council. This standard was also reviewed by the CSA Subcommittee on Electrical Motor-Operated Cleaning Appliances for Commercial Use, under the jur
49、isdiction of the CSA Technical Committee on Consumer and Commercial Products, the CSA Strategic Steering Committee on requirements for Electrical Safety, and has been formally approved by the CSA Technical Committee. This standard has been approved by the American National Standards Institute (ANSI) as an American National Standard. Application of Standard Where reference is made to a specic number of samples to be tested, the specied number is to be cons
