The AT/ATR-MS series ac current transducer combines a current-sensing element and signal conditioner into a single package. The large split-core design allows for installation over existing conductors without the need to disconnect the load, even in applications with multiple conductors per phase. A 4- to 20-mA signal is proportional to the ac current and is compatible with most automation systems. The transducer is loop-powered, meaning it uses the “live zero” output to verify proper connections when the sensor output is 4 mA with no current through the sensing ring. It is UL- and CUL-listed and CE-marked.