Description

Fuse holders are devices for containing, protecting and mounting fuses. Fuse holders come in two basic types, open or fully enclosed. Open fuse holder types are fuse clips, fuse blocks, socket and plug-on cap varieties. The fully enclosed variety may use a fuse carrier that is inserted into a holder or have other means to fully enclose the fuse.

Sizes and Specifications

Standard fuse sizes range from ¼” diameter, 5/8” length (1AG) to ¼” diameter 1” length (8AG), to 5mm x 20 mm, pico fuses and automotive blade.  "Automobile Glass" fuses use the term "AG" in the fuse size designation. Bakelite fiber, ceramic or other similar material fuses use the term "AB" instead of "AG" in the size designation, but retain the dimensions of the "AG" types. Automotive blade fuse sizes differ from glass tube sizes due to the shape of the fuse.  Important performance specifications to consider when searching for fuse holders include normal operating current, rated operating voltage, and power dissipation capacity.  The maximum power dissipation (self-heating) of the fuse used with the fuse holder. Also called the Rated Power Acceptance. The minimum conducting path or conductor cross-sectional area of the conductor connected to the fuse holder should also be considered.

Mounting

Mounting choices for fuse holders include fuse block, fuse clip, panel mount, PC mount, snap mount, and in-line mount.  Important environmental parameters to consider when specifying fuse holders include operating temperature.

Features

Common features for fuse holders include waterproof, vibration resistant, and blow fuse indicator.

Standards

Approvals and ratings for fuse holders include UL, CSA, BSI, VED, IEC (UMF), SEMKO, and Dentori.

The UL Listing guarantees that a fuse has been manufactured in full compliance with the UL 248-14 standard. UL recognition, c-UL Listing, c-UL Recognition, c-UL-us Listing and c-UL-us Recognition does not imply full compliance with UL-248-14. 

CSA Canadian approval that guarantees the a fuse or fuse holder has been manufactured in full compliance with the CSA C22.2 No. 248.14 or CSA C22.2 No. 39 standard, respectively.

The BSI British approval guarantees that a fuse has been manufactured in full compliance with the appropriate section of IEC 60127 (BS 4265) standard.

The VDE German approval guarantees that a fuse or fuse holder has been manufactured in full compliance with the appropriate section of the IEC 60127 standard.

IEC approval applies to Universal Modular Fuses (UMF) that have been found to be compliant with IEC 60127-4. 

SEMKO Swedish approval guarantees that a fuse or fuse holder has been manufactured in full compliance with the appropriate section of the IEC 60127 standard.

Dentori Japanese approval guarantees that a fuse has been manufactured in full compliance with the Japanese MITI stand.

Links to the above standards are listed below.

IEC 60127-1 - Definitions for miniature fuses and general requirements for miniature fuse-links

IEC 60127-4 - Universal modular fuse-links (UMF)

CSA C22.2 - General requirements - Canadian electrical code, part II

UL 248 - Low voltage fuses

References

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Allen-Bradley/Rockwell | Memory Protection Devices