The Littelfuse SymCom LSRX is an AC current sensor designed to energize the output contact whenever 4.5 Amps or greater is present. The LSRX is used commonly as an AC current proof relay to indicate if a motor is operating. It can also be used to interlock fans, compressors and motors; to indicate equipment status such as feed rates, tool wear, loss of prime on pumps, mixer viscosity and all types of current sensing conditions or to stage pump motors, chillers, or other machinery. This device combines a current transformer (CT), transducer and high current output relay together to switch alarm circuits, contactors and most resistive or inductive loads. The LSRX can perform the function of an auxiliary contact, yet has the advantages of universal application and isolation.