Mars Fuse Cartridge 40A 250V 3" M82040

The Mars M82040 is a 40 amp, 250 volt cartridge fuse in a 3 inch body, supplied for branch circuit and equipment protection in HVAC and general electrical applications.

The 250 volt rating suits single phase 120/240 volt systems and 240 volt three phase distribution, covering the majority of residential and light commercial mechanical equipment. The 3 inch body length is a dimensional specification that must match the fuse holder or disconnect clips; cartridge fuses of the same amperage are produced in several body lengths and diameters, and a mismatch will either not seat or will make poor contact.

At 40 amps this fuse commonly protects residential and light commercial condensing units, heat pump outdoor sections, fan and pump motor circuits, and equipment subfeeds.

Applications include fused disconnect switches at outdoor air conditioning equipment, refrigeration condensing units, motor branch circuits, and general distribution in fused panelboards.

Poor clip contact is a frequent and underdiagnosed cause of repeat fuse failure. Spring clips lose tension over years of thermal cycling, and the resulting high resistance connection generates heat that opens the fuse element prematurely. When replacing a fuse that has failed without an obvious circuit fault, inspect the clips for discoloration, pitting, and spring tension, and check terminal torque.

Confirm the class designation, voltage rating, amperage, body dimensions, and time delay characteristic match the original before installation. De-energize and lock out the circuit and verify absence of voltage with a meter before opening the disconnect.

Brand

Mars

SKU

M82040

Category

Fuses

Weight

0.12 lbs

Dimensions

3.00" x 0.81" x 0.81"

Price

$34.00

Availability

In stock

Rating

0 / 5.0