1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL 412 Refrigeration Unit CoolersUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM ULUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REP
2、RODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL UL Standard for Safety for Refrigeration Unit Coolers, UL 412 Fifth Edition, Dated August 22, 2011 Summary of Topics This revision to UL 412 is being issued to remove the reference to the withdrawal date of UL 873 and UL 244A and to address univer
3、sal upkeep of UL Standards for Safety. These revisions are considered to be non-substantive and not subject to ULs STP process. 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 wi
4、th a vertical line in the margin and are followed by an effective date note indicating the date of publication or the date on which the changed requirement becomes effective. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form
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9、hs, 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 effective date are located after the Standard, and are preceded by a SU
10、PERSEDED REQUIREMENTS notice. SEPTEMBER 17, 2013 UL 412 tr1UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL SEPTEMBER 17, 2013 UL 412 tr2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITH
11、OUT PERMISSION FROM UL AUGUST 22, 2011 (Title Page Reprinted: September 17, 2013) 1 UL 412 Standard for Refrigeration Unit Coolers First Edition April, 1979 Second Edition April, 1980 Third Edition September, 1993 Fourth Edition April, 2004 Fifth Edition August 22, 2011 This ANSI/UL Standard for Saf
12、ety consists of the Fifth edition including revisions through September 17, 2013. The most recent designation of ANSI/UL 412 as an American National Standard (ANSI) occurred on August 16, 2012. ANSI approval for a standard does not include the Cover Page, Transmittal Pages, Title Page, or effective
13、date information. The Department of Defense (DoD) has adopted UL 412 on April 9, 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 Standard may be submitted to UL at any time. Proposal
14、s 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 way. All of ULs Standards and all copyrights, ownershi
15、ps, and rights regarding those Standards shall remain the sole and exclusive property of UL. COPYRIGHT 2013 UNDERWRITERS LABORATORIES INC. ANSI/UL 412-2012UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL AUGUST 22, 2011 REFRIGERATION UNIT COO
16、LERS - UL 412 2 No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL CONTENTS INTRODUCTION 1 Scope .6 2 General 6 2.1 Units of measurement .6 2.2 Undated reference 6 3 Glossary .6 4 Installation and Operating Instructions .9 C
17、ONSTRUCTION 5 Components 9 6 General .10 7 Gaskets and Seals .10 8 Nonmetallic Material Classication .10 9 Nonmetallic Material Ignition Source Separation .10 10 Nonmetallic Material Application and Location 12 11 Assembly 13 11.1 Mechanical protection .13 11.2 Protection from live parts 16 11.3 Mou
18、nting of parts 19 12 Accessories 20 13 Cabinets and Enclosures 21 13.1 General .21 13.2 Doors and covers 22 14 Barriers 24 15 Field-Supply Connections 24 15.1 General .24 15.2 Terminals .25 15.3 Leads .26 15.4 Grounding .27 16 Internal Wiring and Wiring Methods .27 17 Separation of Circuits .32 18 B
19、onding for Grounding 33 ELECTRICAL COMPONENTS 19 Capacitors .35 20 Current-Carrying Parts 36 21 Electric Defrost Heaters .36 21.1 Heater elements .36 21.2 Heater temperature limiting control .37 22 Insulating Material 37 23 Motors .38 24 Motor Overload Protection .40 24.1 General .40 24.2 Protection
20、 of single-phase motors 40 24.3 Protection of three-phase motors .42 25 Switches and Controllers 43 26 Transformers .45 AUGUST 22, 2011 REFRIGERATION UNIT COOLERS - UL 412 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 27 Valves and Soleno
21、ids .45 28 Circuit Breakers, Fusing Resistors and Supplementary Protectors 46 29 Connectors, Receptacles and Terminals .46 30 Electrical Cable, Conduit and Tubing 47 31 Electrical Insulation Systems .47 32 Electromagnetic Interference Filters .47 33 Fuses and Fuseholders 47 34 Lighting Systems .48 3
22、5 Optical Isolators and Semiconductor Devices 49 36 Outlet Boxes .49 37 Power Supplies .49 38 Terminal Blocks 50 SPACINGS 39 High-Voltage Circuits 50 40 Extra-Low Voltage Circuits .52 REFRIGERATION SYSTEM 41 Refrigerant .53 42 Refrigerant Tubing and Fittings .53 43 Refrigerant-Containing Parts .54 4
23、4 Required Discharge Capacity 56 45 Relief Valves .56 46 Fusible Plugs or Rupture Members .56 PERFORMANCE 47 General 56 47.1 Test voltage .56 47.2 Temperature measurements .57 48 Tests on Nonmetallic Materials .58 49 Input Test 59 50 Temperature Test Cooling Mode 59 51 Electrical Defrost Test .61 52
24、 Dielectric Voltage Withstand Test .62 53 Evaporator Fan Motor Failure Test 63 54 Overow Test 63 55 Static Loading Test .64 56 Defrost Heater Control Tests .64 56.1 Endurance test .64 56.2 Calibration test .64 57 Burnout Test .65 57.1 Burnout defrost heater 65 57.2 Other components 66 58 Burnout Tes
25、t Impedance Protected Motors .66 58.1 Nonmetallic materials evaluation .66 59 Overvoltage and Undervoltage Tests 67 60 Current Overload Test Bonding Conductors and Connections 67 61 Limited Short-Circuit Test 68 61.1 General .68 61.2 Motor overload protective devices 69 AUGUST 17, 2012 REFRIGERATION
26、 UNIT COOLERS - UL 412 4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 61.3 Bonding conductors and connections .70 61.4 Motor circuit conductors and connections .70 62 Accelerated Aging Test Electric Heaters .70 63 Reliability Test Heater T
27、erminations .71 64 Insulation Resistance Test .71 64.1 Electric heaters 71 64.2 Thermal and/or acoustical insulating material 71 65 Strength Tests Pressure Containing Components .72 66 Rupture Member Test .72 67 Fusible Plug Test .73 68 Marking Label Adhesion Tests .73 69 Fastener Strength Test 73 7
28、0 Strain Relief Test .74 MANUFACTURING AND PRODUCTION TESTS 71 Pressure Test 74 72 Production Line Dielectric Voltage Withstand Tests 74B MARKING 73 General 77 74 Refrigerant Markings .80A 75 Electrical Markings 80B 76 Cautionary Markings 84 77 Accessory Markings .85 Appendix A Informational A1 Scop
29、e .A1 AUGUST 17, 2012 REFRIGERATION UNIT COOLERS - UL 412 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL INTRODUCTION 1 Scope 1.1 These requirements cover unit coolers intended for use in refrigerators, freezers, refrigerated warehouses, w
30、alk-in coolers, and the like. They are designed for connection to alternating current (ac) circuits rated not more than 600 volts. 1.2 These requirements do not apply to fan-coil units intended for comfort cooling, heating, or both, or to other air-conditioning equipment or components covered by ind
31、ividual requirements. 1.3 Requirements for installation of unit coolers are included in the National Electrical Code, NFPA 70, and the Safety Standard for Refrigeration Systems, ASHRAE Standard 15. 2 General 2.1 Units of measurement 2.1.1 If a value for measurement is followed by a value in other un
32、its in parentheses, the second value may be only approximate. The rst stated value is the requirement. 2.2 Undated reference 2.2.1 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 standa
33、rd. 3 Glossary 3.1 For the purpose of this Standard, the following denitions apply. 3.2 ACCESSORY An optional electrical device or other component intended for installation in or connection to a unit cooler for the purpose of modifying or supplementing the functions of the unit cooler. It may be fac
34、tory installed or intended for installation by service personnel. 3.3 BARRIER A partition for isolating high-voltage electrical components, separating ignition sources from ammable materials, isolating moving parts and protection of wiring. 3.4 CABINET The part of the equipment that provides physica
35、l protection to insulated wiring, enclosures, moving parts, motors, enclosed electrical parts, refrigeration tubing or other parts that may cause injury to persons. 3.5 CAPILLARY TUBE Device made of tubing with an outer diameter of less than 3/16 in. (4.7 mm) and used to reduce the pressure of the r
36、efrigerant between the condenser and evaporator. It also regulates the refrigerant ow. 3.6 CASCADE SYSTEM A refrigeration system that incorporates two or more independent vapor- compressor refrigeration cycles in series. This is done to acquire low temperatures that may not be readily achieved with
37、a single refrigeration cycle. 3.7 CIRCUITS, ELECTRICAL a) Extra-Low-Voltage A circuit that has an AC potential of not more than 42.4 V peak (30 V rms), and power of 100 VA or less; or a 30 V dc circuit: AUGUST 22, 2011 REFRIGERATION UNIT COOLERS - UL 412 6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR F
38、URTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 1) Supplied by a primary battery, 2) Supplied by a Class 2 transformer, or 3) Supplied by a combination of a transformer and xed impedance that, as a unit, complies with all the performance requirements for a Class 2 transformer. A circu
39、it that is derived from a circuit that exceeds 30 V by connecting resistance or impedance, or both, in series with the supply circuit to limit the voltage and current, is not an extra-low- voltage circuit. b) High-Voltage A circuit involving a potential of not more than 600 volts and having circuit
40、characteristics in excess of those of an extra-low-voltage circuit. 3.8 COMPONENT A device or fabricated part of the unit cooler covered by the scope of a safety standard dedicated to that purpose. When incorporated in a unit cooler, equipment otherwise typically eld installed (e.g. luminaire) is co
41、nsidered to be a component. Unless otherwise specied, materials that compose a device or fabricated part, such as aluminum or copper, are not considered components. Generally, components are incomplete in construction features or restricted in performance capabilities. Such components are intended f
42、or use only under specic, limited conditions, such as certain temperatures not exceeding specied limits. 3.9 CONTROL, DEFROST CYCLE A control that is intended to regulate a normal defrost cycle. 3.10 CONTROL, OPERATING A device or assembly of devices, the operation of which starts or regulates the e
43、nd product during normal operation. For example, a thermostat, the failure of which a thermal cutout/limiter or another layer of protection would mitigate the risk of electric shock, re, or injury to persons, is considered an operating control. Operating controls are also referred to as “regulating
44、controls”. 3.11 CONTROL, PROTECTIVE A device or assembly of devices, the operation of which is intended to reduce the risk of electric shock, re or injury to persons during normal and reasonably anticipated abnormal operation of the appliance. For example, a thermal cutout/limiter, or any other cont
45、rol/circuit relied upon for normal and abnormal conditions, is considered a protective control. Protective controls are also referred to as “limiting controls” or “safety controls” and are investigated under normal and single-fault conditions. 3.12 CONTROL, TEMPERATURE-LIMITING A control which serve
46、s to prevent excessive temperature and is not intended to function during normal defrost cycle. 3.13 DESIGN PRESSURE The maximum acceptable working pressure for which a unit cooler is designed. 3.14 ENCLOSURE The part of the equipment that does one or more of the following: a) Isolates ignition sour
47、ces, b) Renders inaccessible all or any part(s) of the equipment that may otherwise present a risk of electric shock, c) Retards propagation of ame initiated by electrical disturbances occurring within. AUGUST 22, 2011 REFRIGERATION UNIT COOLERS - UL 412 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR F
48、URTHER REPRODUCTION OR DISTRIBUTION WITHOUT PERMISSION FROM UL 3.15 FUNCTIONAL PART A part other than an enclosure or cabinet used to maintain the intended relative physical position of xed or moving parts, or maintain the integrity of the structure. 3.16 IGNITION SOURCE Any high-voltage electrical
49、component not located within an enclosure. 3.17 NONFUNCTIONAL PART A part of the equipment that does not perform a specic function. 3.18 NONFUNCTIONAL PART, SMALL A nonfunctional part having an area of less than 1 ft 2 (0.093 m 2 ) located so it cannot propagate ame from one area to another, and does not connect a possible source of ignition to the other ignitable parts. 3.19 PRESSURE REGULATING RELIEF VALVE Similar to a pressure relief valve except specic
