1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULMAY 4, 20181UL 248-17Outline of Investigation for Low-Voltage Fuses - Part 17: Class CF FusesIssue Number: 3May 4, 2018Summary of TopicsThis third issue of the Outline of Investigation for Low-Vo
2、ltage Fuses -Part 17: Class CF Fuses, Subject 248-17, covers Class CF fuses rated400A or less and 600V. Revisions include expansion of the fuse ratingsfrom 110A to 400A.ULs Outlines of Investigation are copyrighted by UL LLC. Neither a printed norelectronic copy of an Outline of Investigation should
3、 be altered in any way. All ofULs Outlines of Investigation and all copyrights, ownerships, and rights regardingthose Outlines of Investigation shall remain the sole and exclusive property of ULLLC.COPYRIGHT 2018 UL LLCUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WI
4、THOUT PERMISSION FROM ULMAY 4, 2018UL 248-172No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTS1 General 41.1 Scope .44 Classification .45 Characteristics 45.2 Voltage rating 45.3 Current rating 45.5 Interrupting rati
5、ng .45.6 Peak let-through current and clearing I2t characteristics .57 Construction 67.1 Dimensions 68 Tests 98.2 Verification of temperature rise and current-carrying capacity 98.3 Verification of overload operation .98.4 Verification of operation at rated voltage .98.5 Verification of peak let-thr
6、ough current and clearing I2t characteristics .10MAY 4, 2018 UL 248-17 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL1 GeneralNote: This Outline of Investigation is intended to be read together with the Standard for Low-Voltage Fuses Part 1
7、: GeneralRequirements, UL 248-1, hereafter referred to as Part 1. The numbering of the Clauses in this Outline of Investigation correspondsto like numbered Clauses in UL 248-1. The requirements of UL 248-1 apply unless modified by this Outline of Investigation. ForClauses not shown below, refer to t
8、he Standard for Standard for Low-Voltage Fuses Part 1: General Requirements, UL 248-1.1.1 ScopeThis Part applies to Class CF fuses rated 400 A or less and 600 V ac. DC ratings are optional.4 ClassificationClass CF fuses are non-renewable, current-limiting, and size-rejecting with an interrupting rat
9、ing up to300,000 A. Class CF fuses are divided into five body sizes with the maximum current rating In for eachsize specified in this Part.Time-delay ratings are optional.5 Characteristics5.2 Voltage ratingFor AC, the rating shall be 600 V ac.The DC voltage rating may be different from the AC rating
10、.5.3 Current ratingRefer to Figures A and B for range of current ratings in each body size.5.5 Interrupting ratingFor AC - 200,000 A or 300,000 A at the manufacturers option.For DC, the preferred ratings are 10,000, 20,000, 50,000, 100,000, 150,000, or 200,000 A.MAY 4, 2018UL 248-174UL COPYRIGHTED M
11、ATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL5.6 Peak let-through current and clearing I2t characteristicsMaximum values of peak let-through current and clearing I2t are given in Table A (see 8.5.3).Peak let-through currents shall not exceed the levels def
12、ined by the appropriate Let Through Functionspecified in Table A, as verified through measurement of peak let-through currents at 50, 100, 200 and,if applicable, 300kA.Clearing I2t values recorded shall not exceed the limits specified in Table A as verified throughmeasurement of clearing I2t values
13、at 50, 100, 200 and, if applicable, 300kA.Table AMaximum peak let-through current and clearing I2t for CF fusesCurrentrating In,ABetween thresholdand 50 kAAt 100 kA At 200 kA At 300 kAPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeaklet-throughc
14、urrent, AI2t,ampere-squaredsecondsPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeakLet-ThroughFunction1 1,000 8003 1,500 1,2006 2,300 2,00010 3,300 3,00015 4,000 4,00020 5,000 5,00025 6,000 5,50030 6,000 7,000 7,500 7,000 12,000 7,000 18,500 8,400 Y =1E-07x2+0.015x +500035 7,500 12,00040 8,000
15、17,00045 8,500 18,00050 9,000 22,00060 8,000 30,000 10,000 30,000 16,000 30,000 24,367 36,000 Y =1E-07x2+0.02x +6666.770 11,500 50,00080 12,500 60,00090 13,500 75,000100 12,000 60,000 14,000 80,000 20,000 80,000 28,367 96,000 Y =1E-07x2+0.02x +10667110 14,500 100,000125 15,500 150,000150 17,000 175,
16、000175 18,500 225,000200 20,000 300,000225 19,000 250,000 22,500 350,000 33,000 350,000 46,600 420,000250 24,000 450,000300 26,000 600,000MAY 4, 2018 UL 248-17 5Table A Continued on Next PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTabl
17、e A ContinuedCurrentrating In,ABetween thresholdand 50 kAAt 100 kA At 200 kA At 300 kAPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeaklet-throughcurrent, AI2t,ampere-squaredsecondsPeakLet-Throug
18、hFunction350 29,000 800,000400 25,000 1,000,000 30,000 1,100,000 45,000 1,100,000 66,367 1,320,000 Y =3E-07x2+0.05x +216677 Construction7.1 DimensionsFuse dimensions 1-100A are shown in Figure A. Fuse dimensions 110-400A are shown in Figure B.This is generated text for figtxt.MAY 4, 2018UL 248-176UL
19、 COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULFigure ADimensions of Class 1-100A CF fuses in inchesFuse AmpacityDIM (in) Tolerance 1A15A 17.5A20A25A30A 35A40A 45A50A 60A 70A 80A90A 100AA 0.01 1.750 1.750 1.750 2.000 2.000 2.000 2.882 2.882 2.8
20、82B 0.01 1.000 1.000 1.000 1.125 1.125 1.125 1.260 1.260 1.260C 0.01 0.750 0.750 0.750 1.000 1.000 1.000 1.000 1.000 1.000D 0.01 0.667 0.667 0.667 0.667 0.667 0.667 0.649 0.649 0.649E 0.01 0.040 0.040 0.040 0.040 0.040 0.040 0.063 0.063 0.063F 0.01 0.160 0.160 0.160 0.160 0.160 0.160 0.220 0.220 0.2
21、20G 0.01 0.080 0.080 0.080 0.090 0.090 0.090 0.090 0.090 0.090H 0.01 0.200 0.200 0.200 0.290 0.290 0.290 0.290 0.290 0.290I 0.01 0.580 0.580 0.580 0.790 0.790 0.790 0.790 0.790 0.790J 0.01 0.298 0.298 0.298 0.305 0.305 0.305 0.302 0.302 0.302K 0.01 0.458 0.458 0.458 0.465 0.465 0.465 0.533 0.533 0.5
22、33L 0.01 0.580 0.580 0.580 0.580 0.580 0.580 0.790 0.790 0.790M1 0.01 0.115 0.156 0.156 0.179 0.219 0.219 0.245 0.285 0.285M2 0.01 0.115 0.115 0.156 0.179 0.179 0.219 0.245 0.245 0.285N1 0.01 0.115 0.115 0.156 0.179 0.179 0.219 0.245 0.245 0.285N2 0.01 0.115 0.156 0.156 0.179 0.219 0.219 0.245 0.285
23、 0.285P 0.01 0.156 0.156 0.156 0.156 0.156 0.156 0.173 0.173 0.173MAY 4, 2018 UL 248-17 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULFigure BDimensions of Class CF 110-400A fuses in inchesFuse AmpacityDIM (in) Tolerance 110A 125A 150A 175A
24、 225A 250A 300A 350A 400AA MAX 2.950 2.950 2.950 3.500 3.500 3.500B MAX 2.390 2.390 2.390 2.642 2.642 2.642C1 MAX 1.360 1.360 1.360 1.710 1.710 1.710C2 0.01 1.237 1.237 1.237 1.604 1.604 1.604D 0.01 1.496 1.496 1.496 1.496 1.496 1.496E 0.01 0.157 0.157 0.157 0.157 0.157 0.157F 0.01 0.318 0.318 0.318
25、 0.318 0.318 0.318G 0.01 0.177 0.177 0.177 0.343 0.343 0.343H 0.01 0.236 0.236 0.236 0.236 0.236 0.236J 0.01 0.098 0.098 0.098 0.098 0.098 0.098K 0.01 1.043 1.043 1.043 1.425 1.425 1.425L 0.01 0.791 0.791 0.791 1.007 1.007 1.007M1 0.01 0.256 0.315 0.315 0.364 0.423 0.423M2 0.01 0.256 0.256 0.315 0.3
26、64 0.364 0.423N1 0.01 0.256 0.256 0.315 0.364 0.364 0.423N2 0.01 0.256 0.315 0.315 0.364 0.423 0.423P 0.01 0.157 0.157 0.157 0.157 0.157 0.157Q1 0.01 0.394 0.394 0.394 0.394 0.394 0.394Q2 0.01 0.173 0.173 0.173 0.173 0.173 0.173R 0.01 0.055 0.055 0.055 0.055 0.055 0.055S 1 50.0 50.0 50.0 50.0 50.0 5
27、0.0MAY 4, 2018UL 248-178UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL8 Tests8.2 Verification of temperature rise and current-carrying capacity1.0 In Temperature rise1.1 In Current carrying capacity, Inf8.2.3.1 Fuses rated 400A or lessIn add
28、ition to the requirements of Part 1. At the conclusion of the temperature rise test, the test currentshall be increased without interruption to 1.1 Infor a period of not less than 15 min for fuses rated1-225A and not less than 30 min for fuses rated 226 - 400 A. Temperature is not to be monitored du
29、ring thistime.8.2.4 Acceptability of test resultsThe maximum temperature rise shall not exceed the following:Contacts 100 A: 55C; 100 A: 75C.8.3 Verification of overload operationPart 1, Table 4Test 1 1.35 InTest 3 2.0 InTest 5 5.0 Infor time-delay fuses only8.4 Verification of operation at rated vo
30、ltageFor AC Part 1, Table 5Test 1 200 kA or 300kA at manufacturers optionTest 2 Maximum energyTest 3 Threshold ratio. The maximum threshold ratio shall be 30.Test 4a 100 kATest 4b 50 kATest 5b 2.0 InPeak let-through current and clearing I2t recorded during tests 1, 4a and 4b.For DC (optional) Part 1
31、, Table 6Test 1 Interrupting ratingMAY 4, 2018 UL 248-17 9UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTest 2 Maximum energyTest 5a 9.0 Infor time-delay fuses onlyTest 5c 2.0 In8.5 Verification of peak let-through current and clearing I2t c
32、haracteristics8.5.3 Acceptability of test resultsIn addition to the requirements in Part 1: Peak let-through currents shall not exceed the levels defined bythe appropriate Let Through Function specified in Table A, as verified through measurement of peaklet-through currents at 50, 100, 200 and, if applicable, 300kA. Clearing I2t values recorded shall notexceed the limits specified in Table A as verified through measurement of clearing I2t values at 50, 100,200 and, if applicable, 300kA.MAY 4, 2018UL 248-1710
