Merit Brass A6D400R 600V RK1 Time-delay Fuse 400A

Product Description

The MERIT BRASS A6D400R is a Class RK1 time-delay fuse rated for 600 volts and 400 amps. It provides overcurrent protection with a time-delay characteristic that allows temporary inrush currents, such as those produced by motor starts and transformer energizing, to pass without nuisance tripping. The Class RK1 designation indicates a high degree of current-limiting performance, offering superior protection for downstream equipment compared to standard Class K fuses. Licensed electricians and industrial maintenance technicians install this fuse in motor branch circuits, feeder panels, and control panels where both overcurrent and short-circuit protection are required.

This fuse is suited for commercial and industrial electrical systems operating at up to 600 volts AC. Typical applications include motor control centers, distribution panels, and equipment panels where inrush-tolerant, current-limiting protection is needed. The time-delay feature makes it appropriate for circuits with high starting currents, including HVAC compressor circuits, pump motors, and industrial drive systems. It ships one fuse per pack.

Key Features

• 600-volt AC voltage rating for commercial and industrial service
• 400-amp continuous current rating
• Class RK1 current-limiting design provides enhanced downstream equipment protection
• Time-delay characteristic tolerates motor and transformer inrush without nuisance tripping
• One fuse per pack

Compatibility

Designed as an OEM-style replacement for Class RK1 time-delay fuses used in 600-volt industrial and commercial electrical distribution and motor branch-circuit applications.

Installation Notes

Installation must be performed by a licensed electrician in accordance with the National Electrical Code (NEC). Always de-energize and lock out the circuit before removing or installing a fuse. Verify that the fuse holder or disconnect is rated for Class RK1 fuses at 600 volts and 400 amps before installation. Do not substitute a fuse of a different class or higher ampere rating than specified by the equipment manufacturer.

Technical Specifications

• Voltage Rating: 600 volts
• Ampere Rating: 400 amps
• Fuse Class: RK1
• Type: Time-Delay
• Dimensions (L x W x H): 11.750 inches x 2.620 inches x 2.620 inches
• Weight: 3.570 pounds
• Quantity per Pack: 1
• UPC: 78200199225

Standard Information

• Brand: MERIT BRASS
• Manufacturer Part Number: A6D400R