The ICM517 is UL Rated as a Type 2 single-phase surge protective device with a metal, NEMA 3R Rated enclosure and must be installed before the equipment it is intended to protect. It can be installed at the A/C disconnect or an indoor/outdoor electrical panel. Suitable for use on a circuit capable of delivering not more than 10,000 rms symmetrical amperes, 240V max., when protected by a circuit breaker rated 15A-60A max. and 120V minimum.