Class-L fuses are primarily designed for protection of high capacity systems (mains and large feeders) from short circuit and overload conditions and interrupt a current supply of up to 300kA. Raptor Supplies offers a wide range of these fuses from brands like Bussmann and Ferraz Shawmut featuring O-ring seals for providing maximum pressure during current limiting mechanism . Bussmann Class L fuses feature a high-grade silica sand filler for accelerating the fuse response to current surges by producing an arc-quenching effect for increased mechanical strength. These current-limiting fuses produce a time-delay of 4 seconds (minimum) at 500 per cent rated current for close sizing; thus preventing the contacts to open until the temporary current inrush passes. The 600 VAC fuses are not interchangeable with other UL Class fuses and feature bolt-on mounting facility for ensuring proper seating to maintain the contact within the circuit. Ferraz Shawmut Class L Fuses protect feeder circuits and circuit breakers at a continuous current rating ranging from 200 to 6000A. These UL-listed and CSA-certified slow blow fuses, when correctly coordinated, provide a superior level of protection to downstream circuit components preventing nuisance blowout.