Bussmann FNM-20 Fusetron Dual-Element Time-Delay Midget Fuse

Bussmann FNM-20 Fusetron Dual-Element Time-Delay Midget Fuse, 20A 250V

The Bussmann FNM-20 is a Fusetron dual-element time-delay midget fuse rated 20-Amp at 250-Volt AC, designed for non-rejection style fuse holders and fuse blocks. Identified in the manufacturer catalog as a Miniature Fusetron, the FNM-20 pairs a fast-acting short-circuit element with a thermal time-delay element so it can ride through momentary inrush current and temporary overloads without opening unnecessarily. This dual-element construction makes the FNM-20 a practical replacement fuse for control circuits, small motor loads, and other applications where a standard fast-blow fuse would nuisance-trip. The FNM-20 is commonly specified as a replacement for OEM equipment originally supplied with Fusetron-branded fuses of the same amperage and voltage rating.

Key Features

• Amperage Rating: 20-Amp rating sized for control circuits, small motor branch circuits, and other moderate current loads.
• Voltage Rating: 250-Volt AC rating suitable for standard low-voltage power distribution circuits.
• Dual-Element Construction: Combines a spring-loaded short-circuit element with a thermal time-delay element to absorb temporary overloads and inrush current.
• Time-Delay Operation: Fusetron time-delay design reduces nuisance opening on circuits with motor starting current or transformer inrush.
• Midget Fuse Body: Compact Miniature Fusetron-class body style sized to fit midget fuse blocks and holders.
• Non-Rejection Style: Ferrule configuration designed to fit standard non-rejection fuse clips, holders, and blocks.
• Fusetron Series: Part of the Bussmann Fusetron line of dual-element, time-delay fuses.
• Reliable Overcurrent Protection: Time-delay dual-element design helps protect wiring and equipment while avoiding unnecessary fuse replacement from temporary current spikes.

Technical Specifications

• Refer to manufacturer documentation for complete technical specifications.

Typical Applications

• Motor Circuit and Motor Starter Protection
• Control Circuit and Transformer Protection
• HVAC and Refrigeration Equipment Circuits
• General Purpose Branch Circuit Protection
• Lighting Circuit Protection
• Replacement Fuse for Fuse Blocks and Panels

Why Bussmann?

Bussmann is a well-established name in circuit protection, and the Fusetron FNM-20 reflects that focus with a dual-element, time-delay design built to balance dependable overcurrent protection against nuisance opening. Selecting the correct Fusetron midget fuse for non-rejection holders helps maintain proper protection on 250-Volt AC circuits rated for 20-Amp loads, supporting safe, code-compliant operation of the equipment it protects. For facilities and panels that already use Fusetron midget fuses, the FNM-20 offers a like-for-like replacement that keeps overcurrent protection consistent across the electrical system.