UL 248-14-2020 pdf free download

UL 248-14-2020 pdf free download.Low-Voltage Fuses – Part 14 Supplemental Fuses.
4 Classification
Supplemental fuses are constructed so they cannot be installed in fuseholders intended for fuses covered in the other Parts 2, 3,4.6,7,8,9, 10, 11, 12, 13 and 15 of the Low-Voltage Fuse Standard series. Time- delay ratings are optional.
Some supplemental fuses may physically fit into Part 5 — Class G fuseholders. However, supplemental fuses are intended to protect equipment only and are not permitted to be used instead of Class G fuses in branch circuits.
5 Characteristics
5.2 Voltage rating
The DC voltage rating may be different from the AC rating.
5.3 Current rating
60 A or less
5.5 Interrupting rating
For AC — 10,000 A unless otherwise specified below.
The DC interrupting rating may be different from the AC rating.
Microfuse: 50 A minimum interrupting rating
A fuse rated 250 Vac may have a dual interrupting rating. This rating shall be 10,000 A at 125 Vac and a lower interrupting rating at 250 Vac as specified in Table A.
Fuses rated less than 125 Vac may have an interrupting rating less than 10000 A.
Fuses with interrupting ratings greater than 10,000 A shall be rated 50,000 A or 100,000 A, AC.
5.6 Peak let-through current and clearing 12t characteristics
Not specified.
6 Marking
6.1 Marking of fuses
All required markings shall appear on the smallest package.
The term Supplemental Fuse” is the appropriate fuse classification, but it does not have to be marked.
Neither a fuse nor its package shall bear a marking which states or implies that the fuse is current-limiting.
Except for microfuses, the minimum marking on the fuse shall be:
a) the manufacturers name, trademark, or both;
b) current rating including the corresponding unit of measurement: and
c) voltage rating.
For microfuses, the smallest package shall be marked with the required information. Fuses rated above 125 V shall be marked to indicate their current rating. Fuses rated 125 V or less may be marked at the option of the manufacturer. Except for current rating of fuses above 125 V. color coding of microfuses is an acceptable type of marking. When used, the applicable color code scheme shall be marked on the smallest package.
The designation D may be used as a substitute for “Time Delay” (for qualifying fuses only).
7 Construction
7.1 Fuse dimensions
The dimensions of a supplemental fuse are not specified, except envelope dimensions are given for the microfuse in Part 1, Clause 2.2,7.2.UL 248-14-2020 pdf free download.