The Pocket Interrupter One is a hand held, light weight three channel GPS time synchronized cathodic protection current interrupter. It incorporates a lithium polymer battery and sophisticated power management to provide extremely long times between recharging. It can be charged from a variety of power sources, including 5-volt DC via the micro USB connector, or 6 volts to 24 volts AC or DC via a watertight adapter cable. By itself, the Pi-1 is capable of interrupting two CP current sources of up to 1 amp and 20 volts each. Each interruption channel provides On/Off cycles from 1 second to 30 seconds long and can be set to interrupt independently, and on different cycles if desired. Hours of operation can be specified for interruption in half hour increments. With one or more external high current relays connected, a single Pi-1 can interrupt up to ten high current CP power supplies.