Littelfuse KLSR125 125A Class RK1 Fast-Acting Fuse – Knife-Blade – 600VAC/300VDC

The Littelfuse KLSR125 is a Class RK1 fast-acting current-limiting fuse designed to provide reliable short-circuit protection for industrial and commercial electrical systems. As part of the KLSR series, it features a single-element silver link construction that enables rapid response to overcurrent conditions. This fuse is suitable for applications such as variable speed drives, rectifiers, solenoids, and other surge-sensitive equipment, though it must be properly oversized in inductive load applications to avoid nuisance opening due to inrush currents.

Voltage and Rating

• Current Rating: 125 Amps
• Voltage Rating: 600 Volts AC
• DC Voltage Rating: 300 Volts DC
• Interrupting Rating: 200 kA AIR (up to 20 kA @ 300 VDC)

Key Specifications

• Fuse Type: Fast-Acting (F)
• Fuse Class: Class RK1
• Mounting Type: Knife-Blade
• Series: KLSR
• Family Style: Current Limiting Fuse
• Application: Short-circuit protection for industrial equipment

Technical Specifications

• Opening Characteristic: Fast-Acting
• Current Limiting: Yes
• Interrupt Amperage: 200,000 Amps
• Construction: Single-element silver link design
• Equipment Compatibility: Variable speed drives, rectifiers, surge-sensitive devices
• Safety Rating: High interrupting capacity minimizes need for extensive short-circuit calculations

Product Data

• Manufacturer: Littelfuse
• Model Number: KLSR125
• Series: KLSR RK1 Fast-Acting Fuse

Features

• Extremely current-limiting for fast fault interruption
• Reliable interruption up to 200 kA available fault current
• Protects sensitive electronic and industrial equipment
• Compact knife-blade design for standard fuse holders
• Helps reduce equipment damage from short-circuit energy

Returns are easy

You may return items within 30 days of delivery for a refund.

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