The high interrupting rating of the Amp-Trap® A4BT current limiting fuses makes it suitable for protecting mains, feeders and general circuits. The 10 sec time delay at 500% of fuse rating is ideal for large motors and other loads with high inrush currents. A4BT fuses can be applied to normal loads up to its full ampere rating to allow 100% rating of equipment, while also providing superior current limiting ability.