The Siemens SENTRON 3VA9447-0HA20 is a motorized operating mechanism (MO) designed as an accessory for 3VA5 and 3VA6 molded-case circuit breakers in the 400 A and 600 A frame sizes. It accepts a dual-rated control supply of 110-230 V AC (60 Hz) or 110-250 V DC, drawing 250 VA apparent power during operation. The mechanism's make time is 1.7 s typical; break time is 1.3 s typical — figures that matter when sequencing breaker closure in a transfer scheme or coordinating with upstream protective devices.
The 3VA9447-0HA20 measures 138 mm wide by 149 mm deep by 92 mm high. That depth is the key dimension for enclosure selection — it dictates the minimum gland-plate-to-backpanel clearance when the MO is mounted on the breaker face. Terminals accept conductors stripped to 7 mm, consistent with standard ring-tongue or pin-ferrule termination on control wiring.
Environmental range
The 250 V maximum rating applies to the control circuit — verify that the breaker's own voltage rating matches the line side separately.