1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJUNE 21, 20061SUBJECT 1462OUTLINE OF INVESTIGATIONFORMOBILE HOME PIPE HEATING CABLEIssue Number: 4June 21, 2006Summary of TopicsThis fourth issue of the Subject 1462 Outline of Investigation for
2、MobileHome Pipe Heating Cable includes revisions to the Flexing Test for theheating section of the cable.The UL Foreword is no longer located within the UL Standard. For informationconcerning the use and application of the requirements contained in thisStandard, the current version of the UL Forewor
3、d is located onULStandardsInfoNet at: http:/ 1990, 2006 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJUNE 21, 2006SUBJECT 14622No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION
4、 ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 Scope .4CONSTRUCTION2 Heating Conductors .43 Grounding Component .44 Jacket .55 Nonheating Leads .56 Thermostats 5PERFORMANCE7 Heating Section Tests .58 Complete Cable Tests .69 Permanence of Cord Tag and Marking Tests .7MARKING10 Detai
5、ls 811 Installation Instructions .9JUNE 21, 2006 SUBJECT 1462 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 This outline covers mobile home pipe heating cable intended to reduce the likelihood of water freezingin expo
6、sed pipes of mobile homes in accordance with Article 550 of the National Electrical Code,ANSI/NFPA 70.1.2 Cable units employing different heating conductors, insulation, or other forms of construction may beexamined and tested in accordance with the intent of this outline, and if found to be substan
7、tiallyequivalent, may be covered.CONSTRUCTION2 Heating Conductors2.1 The heating conductors shall be insulated with a suitable insulating compound acceptable for use at75C (167F) or higher in wet locations. The minimum thickness of the insulation shall not be less than1/32 inch (0.8 mm) when not pro
8、vided with a nylon jacket and not less than 1/64 inch (0.4 mm) whenprovided with a 4 mil or thicker nylon jacket.2.2 Heating cables which utilize self-regulating positive temperature coefficient (PTC) materials shall beevaluated in accordance with the requirements for such materials. Reference is ma
9、de to the Appendix tothe Subject 1434 bulletin dated February 9, 1978, or to more current PTC requirements as appropriate.3 Grounding Component3.1 The heating section shall be provided with a grounding component that consists of a metallic sheathor braid. If the heating section consists of more than
10、 one conductor, the grounding component may beincorporated on each conductor or all conductors may be enclosed with a common sheath or braid. If thegrounding component consists of the braid, it shall provide at least 80 percent coverage and shall employmaterial that is corrosion resistant. The groun
11、ding component shall have a current-carrying capacity equalto or greater than that of the unit but not less than that of an 18 AWG (0.82 mm2) copper conductor. Thegrounding braid shall be connected to the grounding lead of the nonheating leads.JUNE 21, 2006SUBJECT 14624UL COPYRIGHTED MATERIAL NOT AU
12、THORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL4 Jacket4.1 An optional insulating jacket may be employed over the grounding component.5 Nonheating Leads5.1 The heating section shall be connected to nonheating leads consisting of Type SJ or heavier flexiblecord acceptable
13、for outdoor use that is at least 2 feet (0.61 m) in length. The flexible cord shall not bemore than 6 feet (1.8 m) in length and shall be terminated by a grounding type attachment plug.6 Thermostats6.1 A thermostat for temperature control may be included in the cable assembly. The thermostat shallco
14、mply with the applicable requirements of the Standard for Temperature-Indicating and -RegulatingEquipment, UL 873.PERFORMANCE7 Heating Section Tests7.1 The heating section of the cable shall be subjected to the tests specified in Table 7.1.Table 7.1Tests for heating section of the cableTest ResultsO
15、vervoltage testa) 135 percent of rated voltage for 2 hours a) There shall be no damage to the insulation on theheating section or surrounding material.b) 200 percent of rated voltage for 2 minutes b) There shall be no damage to the insulation on theheating section or surrounding material.Flexing Tes
16、tThe heating cable shall comply with the Flexing of ShieldedCable Test of the Reference Standard for Electrical Wires,Cables, and Flexible Cords, UL 1581.Conductors shall not open in fewer than 15, 000 cycles.Impact TestWith flat plate, 5 pounds 1-1/4 inch diameter cylindricalweightShall withstand 1
17、5 foot-pounds.Abrasion TestaConducted only when insulating jacket is employed overgrounding component. Samples abraded by No. 1/2 emerycloth mounted on a curved plate, 3-1/2 inch radius, withsample supporting a 3/4 pound weight.Shall withstand 4000 cycles.Ground Component AmpacityThe ground componen
18、t is to be caused to carry a currentof:a) 135 percent of the branch circuit overloadprotection for 1 hour, andb) 200 percent of the branch circuit overloadprotection for 2 minutes.There shall be no damage to the insulation on the heatingsection.Cold BendJUNE 21, 2006 SUBJECT 1462 5Table 7.1 Continue
19、d on Next PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTable 7.1 ContinuedTest ResultsThe heating section is to be cooled to minus 35C (minus31F) for 1 hour and then wrapped around a metal mandrel3/8 inch (9.5 mm) in diameter.The insula
20、tion shall not crack.Flame TestThe heating section is to be subjected to the flame test inaccordance with the Standard for Thermoplastic-InsulatedWires and Cables, UL 83.The insulation shall not flame more than 1 minute after thefinal application of the test flame nor shall flame beconveyed during,
21、between, or after any application of thetest flame.aMay be omitted for units having outer braid or metallic sheath.8 Complete Cable Tests8.1 The complete cable shall be subjected to the tests specified in Table 8.1. Tests on PVC pipe areconsidered representative of metal pipe as well.Table 8.1Tests
22、for the complete cableTest ResultsInput The input shall be within 5 percent of the rated inputvalue of the unit when in the normal operating airtemperature.Temperature Under normal operation no material shall be exposed to atemperature over its rating. References to be made to theStandard for Electr
23、ic Heating Appliances, UL 499.Dielectric Voltage WithstandTwice rated voltage plus 1000 volts. There shall be no indication of dielectric breakdown.Abnormal Operationa ) Units installed on pipe with no spacing between adjacentturns and covered with:1) Thermal insulation, and2) Loosely wadded tissue
24、paper.a) There shall be no fire or other conditions that mayinvolve a risk of electric shock or injury to persons.b) Installed on pipe with heating section crossing itself andcovered with thermal insulation.b) There shall be no fire or other conditions that mayinvolve a risk of electric shock or inj
25、ury to persons.c) One-half of the heating section is to be installed on a pipein accordance with the manufacturers instructions and theremaining section of the heating unit allowed to fall atrandom in a steel pail and covered with tissue paper.c) There shall be no fire or other conditions that mayin
26、volve a risk of electric shock or injury to persons.JUNE 21, 2006SUBJECT 14626UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL9 Permanence of Cord Tag and Marking Tests9.1 To determine compliance with 10.2, representative samples are to be sub
27、jected to the conditioningdescribed in Table 9.1 and then are to be tested in accordance with 9.2 9.5. Upon completion of thetesting, each cord tag sample shall comply with the following requirements.a) The tag shall not tear more than 1/16 inch (1.6 mm) at any point;b) The tag shall not separate fr
28、om the power-supply cord;c) The tag shall not slip or move along the length of the power-supply cord more than 1/2 inch(12.7 mm);d) The tag shall not permanently shrink, deform, crack, or result in any other condition thatwould render the markings or illustrations on the tag illegible; ande) Overlam
29、ination on the tag shall remain in place and not be torn or otherwise damaged, andthe printing shall remain legible.9.2 In determining compliance with 9.1(d), manipulation is permissible, such as straightening of the tagby hand.9.3 For each type of conditioning specified in Table 9.1, three samples
30、of the tag applied to thepower-supply cord in the intended manner are to be used. If tags are applied by an adhesive, tests areto be conducted no sooner than 24 hours after application of the tag.Table 9.1Exposure conditionsExposure conditions Time of evaluationAt least 72 hours in a standard atmosp
31、here.aFollowing the exposure period, under the exposureconditions.At least 24 hours in a standard atmosphereafollowed byimmersion in demineralized water for 48 hours at 23C(73F).Wile still wet after removal from the water.bAt least 24 hours in a standard atmosphereafollowed by 10days in a circulatin
32、g-air oven at the test temperaturecorresponding to the rated surface temperature (60C).After cooling in a standard atmosphere.aAt least 24 hours in a standard atmosphereafollowed by 7hours in a cold box at the lowest temperature (minus 35C)intended for use.Immediately upon removal from the cold box,
33、 avoidingwarming as much as possible.At least 24 hours in a standard atmosphereafollowed byexposure to ultraviolet light and water for 720 hours.Following the exposure period.baStandard atmosphere, 23 2C (73.4 3.6F) and a relative humidity of 50 5 percent.bLabels as attached to porous surfaces are t
34、o be dried at 40C (104F).9.4 Each sample is to consist of a length of power supply cord to which the tag has been applied. Thepower supply cord, with the attachment plug pointing up, is to be held tautly in a vertical plane. A force of5 pounds (22.2 N) is to be applied for 1 minute to the upper most
35、 corner of the tag farthest from the powersupply cord, within 1/4 inch (6.4 mm) of the vertical edge of the tag. The force is to be applied verticallydownward in a direction parallel to the major axis of the cord.JUNE 21, 2006 SUBJECT 1462 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUC
36、TION ORDISTRIBUTION WITHOUT PERMISSION FROM UL9.5 To determine compliance with 9.1(e), each sample is to be scraped ten times across printed areasand edges, with a force of approximately 2 pounds (8.9 N), using the edge of a 5/64 inch (2.0 mm) thicksteel blade held at a right angle to the test surfa
37、ce.MARKING10 Details10.1 Each complete unit shall be provided with a cord tag located not more than 3 inches (76.2 mm) fromthe attachment plug of the flexible cord. The cord tag shall be legibly and permanently marked with themarkings and the illustrations shown in Figure 10.1. For other than the wo
38、rd WARNING, equivalentmarkings and illustrations may be used.Exception No. 1: A cable construction that self-regulates the maximum temperature on the surface of thecable to a temperature of 90C (194F) or less when subjected to the temperature and abnormal operationtests need not be marked concerning
39、 adjacent, twisted, or crossed-over turns.Exception No. 2: A cable construction that is not affected by twisting, such as a round construction, neednot have the reference to twisting in the marking.This is generated text for figtxt.10.2 The cord tag shall be permanently attached to the flexible cord
40、 and shall be made of substantialmaterial (cardboard, cloth, plastic, or the equivalent) to provide mechanical strength and to prevent easyremoval. The cord tag shall comply with the requirements in 9.1.Figure 10.1Cord tag for mobile home pipe heating cableJUNE 21, 2006SUBJECT 14628UL COPYRIGHTED MA
41、TERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL10.3 The markings and illustrations shall be:a) Paint-stenciled, die-stamped, molded, or indelibly stamped,b) In the form of a pressure-sensitive label, orc) In a form that has been determined to be equivalent.10
42、.4 A pressure-sensitive label shall comply with the applicable requirements for labels for outdoor usein the Standard for Marking and Labeling Systems, UL 969. Rated surface temperatures are consideredto be 60C (140F) for high temperature and minus 35C (minus 31F) for low temperature.10.5 The word W
43、ARNING on the cord tag shall be in letters not less than 3/32 inch (2.4 mm) high. Theremaining statements shall be in letters not less than 1/16 inch (1.6 mm) high.10.6 All statements and illustrations shall be printed or illustrated so as to contrast with the background.11 Installation Instructions
44、11.1 Installation instructions shall be provided with each complete unit and shall include a statement thatan extension cord shall not be employed to reach the receptacle.JUNE 21, 2006 SUBJECT 1462 9UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULJUNE 21, 2006SUBJECT 146210No Text on This Page
