UL 248-11:2005 pdf download – Low-Voltage Fuses一Part 11: Plug Fuses.
This Parr is intended w be read together with the Standard for Low-Voltage Fuses — Part 1: General Requirements. hereafter referred to as Parr). The numbering of the Clauses in this Part correspond to like numbered Clauses in Parr I. The requirements of Part I apply unleSS modified by this Parr. For Clauses not shown below, refer to the Standard for Low-Voltage Fuses — Part I:
General Requirements. NMX-J-009/248/ll-2000-ANCE• (AN/CSA C22.2 No. 248.1 • UL 248-I.
1.1 Scope
This Part applies to plug fuses rated 30 A or less and 125 V ac (127 V ac for Mexico). DC ratings are optional.
4 Classification
Plug fuses are non-renewable and not current limiting, with an interrupting rating of 10,000 A. Plug fuses
are divided into 3 sub-classifications. Time-delay ratings are optional.
Plug fuses which are interchangeable for all current ratings. No rejection feature is used. See Figure A.
Typc C
Plug fuses which have a non-interchangeable feature for 3 current ranges (0 — 15, 16 — 20, and 21 — 30 A). See Figure A.
Type S
Plug fuses which have a non-interchangeable feature for 3 current ranges (0 — 15, 16 — 20, and 21 — 30 A). See Figure B,
In Canada only, Type C and Type S fuses may be used, and for all ratings 15 — 30 A, these fuses shall have low melting point “P” (“D” for time delay) characteristics.
5.2 Voltage rating
For AC, the rating shall be 125 V ac or, for fuses intended for installation in Me xico, the rating shall be
127 V ac.
The DC voltage rating may be different from the AC rating.
5.3 Current rating
30 A and less.
5.5 Interrupting rating
For AC- 10,000 A
For DC- 10,000 A
6 Marking
6.1 Marking of fuses
c) voltage rating is optiona l;
d) interrupting rating is optional;
e) fuse class ification is optional; and
g) a plug fuse shall not be marked “Current Limiting.”
In addition to the requirements in Part 1: A plug fuse rated 15 A or less shall have a prominent be xagonal feature. Fuses for Canada shall have a low me lting point characteristic and shall be marked with a “P”or with a “D” for time de lay.
7.3 Connections
The design ofa plug fuse shallbe such that there are no exposed contact parts, or other live parts whe n
the fuse is in the fuseholder.
7.3.1 Edison-base and Type C plug fuses
The screwshellofa fuse shall be formed from brass or other suitable copper alloy not less than 0.20 mm (0.008 in) thick. The thickness after forming shallnot be less than 0.165 mm (0.0065 in), measured on the flat surface of the bottom of the shell.
If the fusible element is exterma ly soldered to the scre ws he lI ne ither the fus ible link nor solder shall extend more than 20.6 mm (0.81 in) above the plane of the center contact, and the solder shall not extend farther from the axis of the fuse than the farthest point on the screw she lI.
The fuse shall fit the go gauge as shown in Figure C, and also shall not fit the no go gauge as shown in Figure D.