Mersen a50p90-4 Fast-acting Semiconductor Blade Fuse 90A

Product Description

The MERSEN a50p90-4 is a fast-acting semiconductor blade fuse rated at 90 amps and designed for overcurrent protection in power electronics and drive systems. Sized at 3.625 inches overall length with a 1-inch diameter body, it is built to interrupt fault currents quickly, protecting sensitive semiconductor components such as SCRs, diodes, and IGBTs from damage. The fuse is rated for 500 VAC and 450 VDC service with an interrupting capacity of 100 kA at AC and 79 kA at DC. Electricians and drive system technicians install this type of fuse in variable frequency drives, rectifiers, and industrial power conversion equipment where rapid, current-limiting response is required.

The a50p90-4 is suited for commercial and industrial electrical installations where semiconductor protection is critical. Typical applications include VFD panels, power rectifier assemblies, and motor control centers. Its fast-acting design ensures the fuse clears a fault before the fault current reaches a level that would destroy downstream semiconductor devices. This makes it a standard specification item in industrial automation, HVAC drive systems, and process control panels.

Key Features

• Fast-acting current-limiting action protects semiconductor devices during fault conditions
• 90-amp continuous current rating
• Dual voltage rating: 500 VAC and 450 VDC
• High interrupting capacity: 100 kA at AC, 79 kA at DC
• Compact blade-style form factor: 3.625 inches OAL, 1-inch diameter
• Suitable for VFD, rectifier, and power conversion panel applications

Compatibility

Designed as an OEM-style semiconductor blade fuse for use in industrial power electronics panels, variable frequency drives, and rectifier assemblies requiring a 90-amp fast-acting fuse at 500 VAC or 450 VDC ratings.

Installation Notes

Installation should be performed by a licensed electrician in accordance with the NEC and applicable local codes. De-energize and lock out the equipment completely before removing or installing the fuse. Verify that the replacement fuse amperage, voltage rating, and interrupting capacity match the panel schedule and equipment manufacturer requirements before energizing. Do not substitute a standard general-purpose fuse for a semiconductor-rated fuse in drive or rectifier circuits.

Technical Specifications

• Amperage: 90 amps
• Voltage Rating: 500 VAC / 450 VDC
• Interrupting Capacity (AC): 100 kA
• Interrupting Capacity (DC): 79 kA
• Overall Length (OAL): 3.625 inches
• Diameter: 1 inch
• Fuse Type: Fast-Acting Semiconductor Blade

Standard Information

• Brand: MERSEN
• Manufacturer Part Number: a50p90-4