Motorized stored-energy mechanism for 3VA2 breakers
The Siemens SENTRON 3VA9267-0HC30 is a motorized operating mechanism with a stored energy mechanism (SEO) designed as an accessory for 3VA2 molded case circuit breakers in frame sizes 100 A, 160 A, and 250 A. It provides remote electrical closing and opening of the breaker, with the stored-energy spring ensuring consistent closing speed independent of operator action. Rated control supply voltage covers 110 V to 240 V AC at 60 Hz minimum to maximum, and 110 V to 250 V DC, drawing 300 VA of operating apparent power. Make and break times are both a typical 0.08 s, giving predictable switching performance for coordinated protection schemes. Panel footprint measures 162.8 mm deep by 105 mm wide by 118.7 mm high. The stripped length for connections is 7 mm.
This motor operator mounts directly onto the 3VA2 breaker frame — no additional brackets or adapters needed for the 100 A, 160 A, or 250 A frame sizes. The stored-energy mechanism means the breaker closes at full speed regardless of how slowly the motor charges the spring, which matters for maintaining consistent contact wear and arc-quench timing across repeated operations. Control wiring lands on the integrated terminal block; the 7 mm strip length is the spec for solid or ferruled stranded conductors. The 300 VA inrush at coil pickup should be factored into the control transformer sizing — a 500 VA transformer is common practice for a single operator on a panel with other control loads.