MegaSurge™ Inrush Current Limiters Ametherm MegaSurge™ Inrush Current Limiters are the economical and space saving solution to limit high inrush current. MegaSurge’s rugged design and high temperature construction allows safe operation at high continuous currents. The Megasure™ Inrush Current Limiters are able to withstand up to 50 amperes of steady state current and 75 to 900 joules of input energy. Applications include plasma cutting tools, motor drives, MRI machines, audio amplifiers, toroidal transformers, and battery chargers.