UL 248-10:2011 free download

UL 248-10:2011 free download Low-Voltage Fuses – Part 1 0: Class L Fuses
1 General
NOTE –
This Part is intended to be read together with the Standard for Low-Voltage Fuses – Part 1 : General Requirements,hereafter referred to as Part 1 . The numbering of the clauses in this Part corresponds to like numbered Clauses in Part 1 . The requirements of Part 1 apply unless modified by this Part. For Clauses not shown below, refer to the Standard for Low-Voltage Fuses – Part 1 : General Requirements, NMX-J-009/248/1 -ANCE ♦ CSA C22.2 No. 248.1 -1 1 ♦ UL 248-1 .
1.1 Scope
This Part applies to Class L fuses rated 1 00 – 6000 A and 600 V ac. DC ratings are optional.
4 Classification
Class L fuses are non-renewable, current-limiting bolt-in type with an interrupting rating of 200,000 A, or at the manufacturer’s option 300,000 A . Class L fuses are divided into nine body sizes with the maximum current rating I n for each size specified in this part. Time-delay ratings are optional.
5 Characteristics
5.2 Voltage rating
For AC, the rating shall be 600 V ac.
The DC voltage rating may be different from the AC rating.
5.3 Current rating
Refer to Figure A for the range of current ratings in each body size.
5.5 Interrupting rating
For AC, 200,000 A or 300,000 A at the manufacturer’s option (300,000 A not applicable in Mexico).
For DC, the preferred ratings are 20,000, 50,000, 1 00,000, 1 50,000, 200,000, or 300,000 A.
5.6 Peak let-through current and clearing I 2 t characteristics Maximum values of peak let-through current and clearing I 2 t are given in Table A (see 8.5.3). Peak let-through currents shall not exceed the levels defined by the appropriate Let Through Function specified in Table A, as verified through measurement of peak let-through currents at 50, 1 00, 200, and, if applicable, 300 kA. Clearing I 2 t values recorded shall not exceed the limits specified in Table A as verified through measurement of clearing I 2 t values at 50, 1 00, 200, and, if applicable, 300 kA.
6 Marking
6.1 Class L fuses may be marked ″Time Delay.″
7 Construction
7.1 Dimensions
Fuse dimensions are shown in Figures A and B.
7.2 Current-carrying parts
7.2.1 The terminals of Class L fuses shall be electroplated with nickel, silver, or tin, or treated by other means to provide equivalent protection.