What this part is and what it fits
The Siemens SENTRON 3VA9157-0HA10 is a motorized operating mechanism (MO) — a remote-switching accessory designed specifically for the 3VA1 160 frame molded case circuit breaker. It lets you open or close the breaker from a PLC, pushbutton station, or automation controller without a technician pulling the handle. Control voltage range is 24 to 60 VDC, covering standard 24 VDC control loops and higher-voltage truck/bus battery systems. The mechanism draws 250 VA apparent power during the make/break stroke, so size the control transformer or DC supply for that inrush — it's not a continuous load. Make and break times are both 0.8 s typical, which is a deliberate slow-speed stroke to reduce mechanical stress on the breaker mechanism and avoid nuisance tripping from shock. That 0.8 s is fine for load shedding, emergency stop, or remote disconnect sequences; it is not a fast-transfer switch.
Physical fit and panel integration
Depth 103 mm, width 76 mm, height 70 mm. The 76 mm width matches the standard 4-module-wide (4 MW) DIN-rail footprint of the 3VA1 160 breaker itself, so the operator mounts directly on the breaker front without stealing adjacent space. Verify the enclosure depth clears 103 mm plus wiring bend radius behind the operator. Ambient range -40 °C to 80 °C covers cold storage, unheated electrical rooms, and high-temp machine cabinets. The 7 mm stripped length on the control wiring is standard for spring-cage or screw terminals on the operator.