Merit Brass AJT225 Class J Time-delay Fuse 225A 600V

Product Description

The MERIT BRASS AJT225 is a Class J time-delay fuse rated for 225 amps at 600 volts, designed for use in commercial and industrial electrical distribution systems. Class J fuses provide current-limiting protection, interrupting fault currents rapidly to protect downstream equipment from damage. The time-delay characteristic allows the fuse to tolerate brief motor-starting inrush currents without nuisance opening, while still responding decisively to sustained overloads and short-circuit events. Licensed electricians install this fuse in fusible disconnect switches and panelboards where Class J form factor and current-limiting performance are specified.

This fuse is suited for branch-circuit and feeder protection in commercial buildings, light industrial facilities, and mechanical equipment rooms. Common applications include motor branch circuits, HVAC equipment disconnects, and service entrance protection where a 225-amp Class J fuse is required by design or code. The compact Class J form factor prevents substitution of lower-rated fuse classes, a key safety feature in properly coordinated systems.

Key Features

• 225-amp continuous current rating at 600 volts AC
• Class J current-limiting design for fast fault interruption
• Time-delay action tolerates motor-start inrush without nuisance opening
• Class J form factor prevents cross-class substitution
• Packaged individually — 1 fuse per pack

Compatibility

Designed as an OEM-style replacement Class J fuse for use in any fusible disconnect switch or panelboard that accepts a standard 225-amp Class J fuse holder.

Installation Notes

Installation must be performed by a licensed electrician in accordance with the National Electrical Code (NEC). De-energize and lock out the circuit at the upstream disconnect or breaker before removing or installing this fuse. Verify that the fuse holder and disconnect are rated for Class J fuses at 600 volts and 225 amps or higher before installation. Do not install a fuse into an energized fuseholder.

WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.