UL 4248-1 PDF

1 Scope

1.1 These fuseholders and devices accommodate fuses to be employed in electrical circuits and are intended to be used in accordance with the Canadian Electrical Code, Part I (CE Code Part I), CSA C22.1, the National Electrical Code, NFPA 70, or the Mexican Electrical Code, NOM-001.

1.2 These requirements cover:

1. a) Fuseholders for fuses intended for use with fuse classes covered in the ANCE NMX-J-009-248; CSA C22.2 No. 248; and UL 248 series of standards, Parts 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15; and

2. b) Fuseholder accessories (such as covers, indicators, adapters, etc.).

1.3 This Standard and its subsequent Parts establish the characteristics, construction, operating conditions, markings, and test conditions for fuseholders.

1.4 The titles of the Clauses in this Part 1 correspond to the similarly titled Clauses in the subsequent Parts.

Summary of Topics

This revision of ANSI/UL 4248-1 dated June 18, 2025 includes the following changes in requirements:

– Addition of “Short-Circuit Current Rating” as an equivalent term; 4.2.3

– Clarification on wire length for temperature test; 11.4.1