Surge-Trap® Surge Protective Device is a no-fuse surge suppressor. The Surge-Trap is a UL 1449 Third Edition compliant modular style surge protective device that is DIN-rail mountable featuring a fail-safe self-protected design, visual indicator and a small foot print. A remote indicator option provides status to critical control circuit. The Surge-Trap provides advanced overvoltage protection utilizing Mersen's patented TPMOV® technology without additional protection devices. 277/480 Volts 3P Wye system type without N-G mode .