When interrupting an arc fault within its current-limiting range, Ferraz Shawmut's Amp-Trap® current-limiting fuses dramatically limit the total energy delivered to the fault.

Reducing the electrical energy delivered to the arc flash event will reduce the amount of heat generated. This decrease in incident heat energy usually reduces the category of personal protective equipment (PPE) required, enabling personnel to work more easily and efficiently.

This calculator can be used to determine incident heat energy at a particular distance and the category of PPE required. Simply enter the bolted fault current, choose a current-limiting fuse from the drop-down menu, and select "calculate." See cautionary notes prior to use.

Calculations are based on three-phase tests at 600V using a 20" x 20" x 20" box, as described in IEEE 1584, Guide for Performing Arc Flash Calculations. They determine the PPE required to protect against the effects of radiated heat, and do not take into account the effects of pressure, molten metal droplets, toxic smoke or plasma jets. Actual arc flash results could be different from the results given here.