Undervoltage release for 3VA breakers
The Siemens 3VA9908-0BB13 is an undervoltage release accessory for the SENTRON 3VA1 and 3VA20 through 3VA25 molded-case circuit breaker families. Rated control supply voltage is 60 V DC, with a maximum power consumption of 2.5 W. The release occupies one of the three accessory slots in the breaker, so it does not consume additional DIN-rail space.
This means the release is designed for fixed-installation distribution panels where transient overvoltages and moderate conductive pollution are expected — typical of industrial control cabinets. The 60 V DC coil voltage is specific: verify your control supply matches. A 24 V DC panel supply will not drive this release. The 2.5 W load is small enough that a standard 60 V DC power supply can drive it without derating. Dimensions are 25.7 mm wide, 65.1 mm high, and 28.8 mm deep. The release mounts entirely inside the breaker accessory pocket — no added panel depth beyond the breaker itself.