Part Identification and Lifecycle
The Siemens SIRIUS 3RT1924-5AH22 is a magnet coil for Size S0 contactors, rated at 48 V AC at both 50 Hz and 60 Hz, with a spring-type terminal for the control circuit. Per the manufacturer's designation, this is a phased-out product; the official successor is the SIRIUS 3RT2 series.
Coil Electrical Characteristics
The coil draws an inrush current of 0.8 to 1.1 A at 50 Hz (the same range applies at 60 Hz). This inrush is the peak current the control transformer or PLC output must deliver to pick the contactor; the holding current is significantly lower. For audit purposes, the control supply must be AC only, as the coil is designed for AC voltage.