The Siemens 3VA9908-0BD13 is a SENTRON universal auxiliary release — a 48 V DC shunt trip accessory designed for the 3VA1 and 3VA20 through 3VA25 molded-case circuit breaker frames. It fits into the breaker's three accessory slots, providing remote tripping capability for emergency-off or interlock circuits.
Rated for 48 V DC with a maximum active power consumption of 20 W, this release is sized for standard 48 V control supplies common in industrial panels. The 4 kV surge voltage resistance and overvoltage category III rating mean it withstands transient overvoltages typical of fixed-installation distribution boards — it won't fail on a switching surge from an upstream contactor or drive. No additional conformal coating or sealed housing is required for typical panel duty. The 28.8 mm depth, 25.7 mm width, and 65.1 mm height define the canister that slides into the breaker's accessory bay. Verify the breaker frame has the three-slot accessory receiver before specifying — this release occupies one slot and does not alter the breaker's external footprint.
Deployment context
Installed inside the 3VA molded-case breaker accessory bay — no DIN-rail space consumed, no additional wiring enclosure needed. The stripped length of 10 mm (0.4 in) on the flying leads matches standard ferrule and terminal-block preparation for control wiring. Typical application: remote shunt trip for an emergency-stop circuit or a safety PLC output driving a contactor to drop the breaker under fault conditions. The 48 V DC coil is held energized in normal operation; removing the control voltage releases the breaker mechanism.