The Siemens 3VA1112-5MH36-0BH0 is a 3-pole IEC molded-case circuit breaker from the 3VA1 frame 160 series, rated 125 A continuous current.
The breaker is configured for starter protection with a TM120M thermal-magnetic trip unit set at 125 A. The 'without overload protection' note means the thermal element is bypassed — this unit provides only short-circuit protection, with adjustable instantaneous pickup (Ii) from 5 to 15 times In. That makes it a fit for motor branch circuits where overload protection is handled separately by an overload relay or soft starter. The undervoltage release (UVR) is 24 V DC.
Deployment context
The clamp connection terminals accept copper or aluminum conductors up to the rated cross-section for the 125 A frame. In a motor control center, it typically sits in the feeder section ahead of the contactor and overload relay, providing the short-circuit protection that the overload relay alone cannot handle.