Cooper Bussmann LPJ-3SP Class J Time Delay Fuse 3A

Product Description

The COOPER BUSSMANN LPJ-3SP is a Class J time-delay cartridge fuse rated at 3 amps, designed for general-purpose overcurrent protection in commercial and industrial electrical systems. Its dual-element, time-delay construction allows temporary inrush currents to pass without nuisance tripping, while still providing fast response to sustained fault conditions. The fuse body measures 2.25 inches in length and 20.6 mm in diameter, fitting standard Class J fuse holders. With an interrupting rating of 300 kA at AC (RMS) and 100 kA at DC, it handles high-fault-current environments where system integrity is critical. Licensed electricians and industrial maintenance technicians are the primary installers.

This fuse is suited for use in commercial HVAC equipment, motor control panels, power distribution boards, and other systems where Class J fusing is specified. The time-delay characteristic makes it a practical choice for protecting motor loads and transformer primaries that draw elevated inrush current on startup. Its compact cartridge form factor installs into any compatible Class J fuse holder without modification. Non-indicating design means the fuse does not provide a visual blown indicator, so continuity testing is required during troubleshooting to confirm fuse condition.

Key Features

• Class J time-delay, dual-element construction tolerates motor inrush without nuisance tripping
• 300 kA interrupting rating at AC (RMS) and 100 kA at DC for high-fault-current protection
• 3-amp rating for low-current branch circuit and control circuit protection
• Cartridge body: 2.25 inches long, 20.6 mm diameter — fits standard Class J holders
• Non-indicating fuse body; requires continuity test to confirm blown status
• CE Certified, CSA Certified, UL Listed, and RoHS Compliant

Compatibility

Designed for use in Class J fuse holders accepting a cartridge fuse with a 20.6 mm diameter body and 2.25-inch overall length. Verify holder ampere rating and voltage rating before installation.

Installation Notes

Installation must be performed by a qualified electrician in accordance with applicable NEC requirements and local electrical codes. De-energize and lock out the circuit before removing or installing any fuse. Confirm that the replacement fuse amperage, voltage rating, and class match the panel or equipment specifications exactly. Do not substitute a standard fast-acting fuse where a time-delay Class J fuse is specified by the equipment manufacturer.