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BUSSMANN Buss Class R Reducer Fuse: Fits Fuse Class R, For Fuse Clip Size 400 A - Fuse Reducers for Cylindrical Fuses
BUSSMANNFuse Reducers for Cylindrical Fuses

BUSSMANN Buss Class R Reducer Fuse: Fits Fuse Class R, For Fuse Clip Size 400 A

The BUSSMANN Buss Class R Reducer Fuse (MPN NO.642-R) is a fuse reducer for cylindrical fuses, designed for fuse clip size 400 A with a minimum fuse size of 0 A. This Class R reducer enables the use of smaller fuses…

SKU 3G-OTH-25547

Brand
BUSSMANN
Item
Buss Class R Reducer Fuse: Fits Fuse Class R, For Fuse Clip Size 400 A
Category
Fuse Reducers for Cylindrical Fuses
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Technical Specifications

BUSSMANN
Manufacturer Part Number
NO.642-R
Type
For Fuse Clip Size 400 A, Min. Fuse Size 0 A
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BUSSMANN Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The BUSSMANN Buss Class R Reducer Fuse (MPN NO.642-R) is a fuse reducer for cylindrical fuses, designed for fuse clip size 400 A with a minimum fuse size of 0 A. This Class R reducer enables the use of smaller fuses in larger fuse clips, supporting flexible circuit protection configurations across industrial electrical systems.

Frequently Asked Questions

What is a BUSSMANN Class R reducer fuse used for?

A BUSSMANN Class R reducer fuse adapts a larger fuse clip to accept a smaller Class R fuse, ensuring proper fit and electrical protection. It is commonly used in industrial panels and motor control centers where fuse size changes are needed without replacing the entire fuse holder.

What are the specifications of the BUSSMANN NO.642-R fuse reducer?

The BUSSMANN NO.642-R is a Class R fuse reducer designed for fuse clip size 400 A, with a minimum fuse size of 0 A. It is manufactured by BUSSMANN and is used to reduce the clip opening for smaller Class R fuses in industrial electrical systems.

Where to buy BUSSMANN NO.642-R fuse reducers worldwide?

You can source BUSSMANN NO.642-R fuse reducers through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring reliable supply for your maintenance or project needs.

How to install a BUSSMANN Class R fuse reducer?

To install a BUSSMANN Class R fuse reducer, first de-energize the circuit. Slide the reducer into the existing 400 A fuse clip, ensuring it seats firmly. Then insert the smaller Class R fuse into the reducer. Always follow manufacturer guidelines and local electrical codes for safe installation.

Used in

Common applications for BUSSMANN
Industrial motor control centers — BUSSMANN LPT series Class T time-delay fuses for branch circuit protection
Semiconductor protection in variable frequency drives — BUSSMANN FWA series fast-acting bolt-on fuses rated 150 V AC/DC
Automotive auxiliary circuit protection — BUSSMANN CB222 series Type II circuit breakers in 12 V DC systems
Control panel overcurrent protection — BUSSMANN FNA series midget time-delay indicating fuses for instrumentation
Main feeder protection in power distribution — BUSSMANN KLU series Class L time-delay bolt-on fuses up to 650 A
Fuse replacement in existing panels — BUSSMANN S-8301-1-R fuse block accepting 3AG and other glass/ceramic fuses

BUSSMANN Products

3G Electric supplies BUSSMANN fuse reducers for cylindrical fuses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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