The Airpax AP series magnetic circuit protectors combine power switching with accurate and reliable circuit protection, incorporating inverse time delays and a trip-free feature. Unlike thermal protectors, the AP maintains a consistent trip current across a wide temperature range. Available in DC, 50/60Hz, or 400Hz versions with various delays, these protectors are designed to meet specific application requirements. The 'trip-free' action ensures the circuit won't remain closed during an overload, even with the handle in the ON position. Waterproof integrity is achieved through an O-ring bushing seal and a silicon rubber gland. The UP series, UL recognized and CSA certified, operates from 50V DC to 240V 50/60Hz. AP-MIL protectors adhere to MIL-PRF-39019 standards and undergo rigorous testing. Typical applications include communication, navigation, aircraft instrumentation, radar, and power supplies.