1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULUNDERWRITERS LABORATORIES INC. CERTIFICATION REQUIREMENT DECISIONThis Certification Requirement Decision is prepared and published by Underwriters Laboratories Inc.(UL). It is normative for the a
2、pplicable UL Product Certification Program(s); however, it is currently notpart of the UL Standard(s) referenced below.Product Category (CCN): XCFR2Standard Number: UL 1059Standard Title: Standard for Terminal BlocksEdition Date: December 27, 2001Edition Number: 4Section / Paragraph Reference: Secti
3、ons 50 and 51 (Performance)Subject: Protective Conductor Terminal Blocks (PCTB) Rated for Use WithAluminum ConductorsDECISION:PART V - PROTECTIVE CONDUCTOR TERMINAL BLOCKS (PCTB)PERFORMANCE50 Short Time Current Sequence (Commercial and Industrial Applications)50.1 General50.1.1 A protective conducto
4、r terminal block (PCTB) or pole of a PCTB intended for use in commercialand industrial applications, as specified in items B and C of Table 8.1, shall be subjected to the testsdescribed in 50.2 - 50.4.50.1.2 The tests are to be conducted on a protective conductor terminal block installed on its supp
5、ortaccording to the manufacturers instructions. The tests are to be repeated for each alternate supportconstruction, support material, or both.50.1.3 A copper conductor of the largest size for which the terminal block is rated, not less than 2 feet(0.609 m) long, is to be installed. A terminal block
6、 rated for use with copper shall be tested with a copperconductor, a terminal block rated for use with aluminum shall be tested with an aluminum conductor, anda terminal block rated for use with both copper and aluminum conductors shall be tested with copper. Theconductor connection and the connecti
7、on to the support are to be made using the torque specified in 10.5.50.2 Voltage drop test50.2.1 The voltage drop is to be measured on each terminal block as shown in Figure 50.1, with a d-ccurrent of 0.1 times the maximum rated current of the terminal block passing through the measurementpoints.a)
8、The voltage drop shall not exceed 3.2 mV, when measured across the clamping units; andb) The voltage drop shall not exceed 6.4 mV, when measured from the clamping units to thesupport.This is generated text for figtxt.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITH
9、OUT PERMISSION FROM UL50.3 Current test50.3.1 Following the measurement of voltage drop, three separate applications of the test currentspecified in Table 50.1 are to be applied, one after another, through the current paths 1-1 and 2-2, asappropriate, as shown in Figure 50.2. The test current is to
10、be applied for 1 second during eachapplication with an interval of 6 minutes or less between applications of the current. There shall be nodamage to the terminal block or its support.Table 50.1Short-time test currentsCopper cConductor size, AWG/kcmil (mm2) Test current, amperesCopper Aluminum14 AWG
11、(2.1) 252 17012 (3.3) 396 27010 (5.3) 636 4308 (8.4) 1008 6806 (13.3) 1596 8804 (21.2) 2544 14003 (26.7) 3204 17702 (33.6) 4032 22301 (42.4) 5088 28001/0 (53.5) 6420 29002/0 (67.4) 8088 36003/0 (85.0) 10,200 4600Figure 50.1Voltage drop measurement pointsSTANDARD NUMBER: UL 1059 -2-UL COPYRIGHTED MAT
12、ERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTable 50.1 ContinuedCopper cConductor size, AWG/kcmil (mm2) Test current, amperesCopper Aluminum4/0 (107) 12,840 5800250 kcmil (127) 15,240 6900300 (152) 18,240 8200350 (177) 21,240 9600400 (203) 24,360 11000500 (
13、253) 30,360 13700600 (304) 36,480 16500700 (355) 42,600 19250750 (380) 45,600 20600800 (405) 48,600 2200900 (456) 54,720 247001000 (507) 60,840 27500This is generated text for figtxt.50.4 Voltage drop test repeated50.4.1 Following the test described in 50.3.1 and after cooling to room temperature an
14、d without anychange to the arrangement, the voltage drop test described in 50.2.1 is to be repeated.a) The voltage drop shall not exceed 3.2 mV, when measured across the clamping units;Figure 50.2Current path for short time current testSTANDARD NUMBER: UL 1059 -3-UL COPYRIGHTED MATERIAL NOT AUTHORIZ
15、ED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULb) The voltage drop shall not exceed 6.4 mV, when measured from the clamping units to thesupport; andc) The voltage drop shall not exceed 150 percent of the voltage drop measured in 50.2.1 (a)and (b).51 Short Time Current Sequence
16、(Service Applications)51.1 General51.1.1 A protective conductor terminal block intended for use in service applications, see item A of Table8.1, shall carry the current specified in Table 50.1 for the time specified in Table 51.1 without damage tothe terminal block or its support. At the conclusion
17、of the test, continuity shall exist when tested asdescribed in 51.3.1 and 51.3.2.Table 51.1Short-time current test durationConductor size AWG/kcmil (mm2) Time, seconds14 (2.1) 412 (3.3) 410 (5.3) 48 (8.4) 46 (13.3) 64 (21.2) 63 (26.7) 62 (33.6) 61 (42.4) 61/0 and larger (53.5) 951.2 Current test51.2
18、.1 A copper conductor of the maximum intended size, not less than 2 feet (0.609 m) long, shall beinstalled. A terminal block rated for use with copper shall be tested with a copper conductor, a terminalblock rated for use with aluminum shall be tested with an aluminum conductor, and a terminal block
19、 ratedfor use with both copper and aluminum conductors shall be tested with copper. A terminal connector shallbe tightened using the torque specified in 10.5. The test current shall pass through the mounting supportand the conductor.51.3 Continuity test51.3.1 After the current test described in 51.2
20、.1, continuity shall exist on the test sample assembly whenmeasured between a point on the mounting support 1/4 inch (6.4 mm) from the connection and a similarpoint on the wire.51.3.2 An indicating device such as an ohmmeter, battery-and-buzzer combination, or similar device shallbe used to determin
21、e if continuity exists.STANDARD NUMBER: UL 1059 -4-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULRATIONALE FOR DECISION:Protective Conductor Terminal Blocks may be used in applications involving both copper and aluminumconductors; however th
22、e Standard for Terminal Blocks, UL 1059, only addresses testing with copperconductors. Values in UL 1059 for copper are based on the IEC Standard for Protective ConductorTerminal Blocks for Copper Conductors, IEC 60947-7-2. These values, which are based on a short-timewithstand current of 120 A/mm2o
23、f the conductors cross-section, are similar to values in the UL Standardfor Grounding and Bonding Equipment, UL 467. The test currents in UL 467 are derived from the followingformula (test values rounded):Where:Tm= 1083C for melting point for copper and 657C for melting point for aluminum and 1510Cf
24、or melting point for steelTa= 40C = ambient temperatureI = short time current (amperes) in kAA = conductor cross section in mm2t = time (s)Ko= reciprocal of thermal coefficient of resistivity at 0C = 234 for copper and 228 for aluminumand 605 for steel = material constant = 19.8 for copper and 45.1
25、for aluminum and 77.5 for steelThe requirements specify that testing is to be conducted with the largest size conductor, and indicates thattesting with copper represents aluminum (for those terminal blocks rated for use with both copper andaluminum), as the test currents for copper are higher than f
26、or aluminum of the same size.The IEC Series of Terminal Block Standards do not address evaluation with aluminum conductors;therefore, this Certification Requirement Decision defers to the test currents in UL 467.Copyright 2015 Underwriters Laboratories Inc.UL, in performing its functions in accordan
27、ce with its objectives, does not guarantee or warrant thecorrectness of Certification Requirement Decisions it may issue or that they will be recognized or adoptedby anyone. Certification Requirement Decisions are the opinion of Underwriters Laboratories Inc. inpractically applying the requirements
28、of the standard. They do not represent formal interpretations of thestandard under American National Standards Institute (ANSI) processes. UL shall not be responsible toanyone for the use of or reliance upon Certification Requirement Decisions by anyone. UL shall not incurany obligation or liability
29、 for damages, including consequential damages, arising out of or in connectionwith the use or reliance upon Certification Requirement Decisions. The electronic version of theCertification Requirement Decision is the current version and previously printed copies may be outdated.STANDARD NUMBER: UL 1059 -5-UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULThis document is published as a service to ULs certification customersSTANDARD NUMBER: UL 1059 -6-
