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.

Technical Specifications

• Amperage: 225 amps
• Voltage Rating: 600 volts
• Fuse Class: Class J
• Type: Time-Delay
• Dimensions (L x W x H): 7.250 inches x 2.120 inches x 2.120 inches
• Weight: 2.000 pounds
• Quantity per Pack: 1
• UPC: 78200196228

Standard Information

• Brand: MERIT BRASS
• Manufacturer Part Number: AJT225