The Siemens 3VA9137-0HA10 is a SENTRON motorized operating mechanism (MO) — a bolt-on accessory that gives a 3VA5 125 molded-case circuit breaker remote switching capability via a DC control signal. If you are specifying or stocking spares for a 3VA5 125 panel, this is the part that lets you close and open the breaker from a PLC or pushbutton without an operator pulling the handle.
Control voltage range is 24 to 60 V DC, so it works across standard 24 VDC industrial supplies and the higher 48–60 VDC rails common in utility and marine panels. The solenoid draws 250 VA during the make or break stroke — that is the peak inrush, not a hold-in power — so size your control transformer or DC supply for that surge. Mechanically it measures 103 mm deep by 76 mm wide by 70 mm high. The stripped length of 7 mm on the control wiring terminals is a reminder to set your wire stripper to that depth — too short and the conductor won't seat in the cage; too long and you risk exposed copper past the terminal.