The Siemens 3VA1112-5EF36-0CH0 is a 3-pole IEC molded-case circuit breaker in the 3VA1 series, frame size 160, with a 125 A thermal-magnetic trip unit (TM240). The overload protection band is adjustable from 88 A to 125 A via the Ir dial, and the instantaneous short-circuit pickup (Ii) is set between 5 and 10 times In, so you can dial it in for motor starts or transformer inrush.
Built-in undervoltage release and auxiliary switching
This breaker ships with an undervoltage release (UVR) rated 120–127 V AC, 50/60 Hz — it drops the trip mechanism if control voltage falls below the dropout threshold, which is standard for emergency-stop chains or mains-monitoring circuits. The clamp-type terminals accept copper or aluminum conductors up to the frame rating.