Mersen A2K45R 250V Class RK1 Time-delay Fuse 45 Amp

Product Description

The MERSEN A2K45R is a 250-volt, 45-amp Class RK1 time-delay fuse designed for overcurrent protection in industrial and commercial electrical systems. Class RK1 fuses provide a high degree of current limitation, making them a reliable choice for protecting motors, transformers, and other inductive loads from short-circuit and overload conditions. The time-delay characteristic allows the fuse to ride through harmless inrush currents while still responding quickly to damaging fault events. Licensed electricians and maintenance technicians install this fuse in fusible disconnect switches, panelboards, and motor control equipment where RK1-class protection is specified.

This fuse is suited for use in residential, commercial, and light industrial electrical systems operating at 250 volts AC or less. Typical applications include motor branch-circuit protection, feeder protection, and service-entrance equipment where current-limiting, time-delay overcurrent protection is required by code or design specification. When replacing an existing fuse, verify that the replacement matches the original voltage rating, amperage, and fuse class before installation.

Key Features

• 250-volt AC voltage rating suitable for single-phase and three-phase circuits at or below 250 volts
• 45-amp continuous current rating for motor and feeder protection applications
• Class RK1 designation provides high current-limitation performance
• Time-delay design tolerates motor inrush without nuisance opens
• Drop-in replacement form factor for existing Class RK1 fuse holders and disconnect switches

Compatibility

Designed as an OEM-style replacement Class RK1 time-delay fuse for use in standard RK1-rated fuse holders, fusible disconnect switches, and panelboard equipment rated at 250 volts and 45 amps.

Installation Notes

Installation should be performed by a qualified electrician in accordance with the National Electrical Code (NEC) and applicable local codes. De-energize and lock out the circuit before removing or installing any fuse. Verify that the fuse holder is rated for Class RK1 fuses and that the circuit voltage and amperage do not exceed the fuse ratings. Never substitute a fuse of a higher amperage or different class than specified for the circuit.

Technical Specifications

• Voltage Rating: 250 volts
• Amperage Rating: 45 amps
• Fuse Class: RK1
• Fuse Type: Time-Delay
• UPC: 78200191514

Standard Information

• Brand: MERSEN
• Manufacturer Part Number: A2K45R