The Siemens 3VA9257-0GX10 is a SENTRON auxiliary switch module with a rotary operator mechanism, designed as an accessory for 3VA1 molded-case circuit breakers in the 100 A, 160 A, and 250 A frame sizes. It provides two auxiliary contacts that lead to the ON position, giving the panel builder a dry-contact status signal that tracks the breaker's closed state — useful for PLC inputs, status lamps, or upstream interlocks. Rated for a thermal current (Ith) of 5 A, the contacts are sized for signal-level switching, not motor loads. The AC-12 rating (5 A at 12 V through 240 V) covers resistive loads like indicator lamps and relay coils; the AC-15 rating (2 A) handles electromagnetic loads typical of contactor coils and solenoid valves. For DC circuits, the DC-13 rating (0.2 A at 12 V through 250 V) governs inductive DC loads — a figure that often surprises buyers expecting the AC number to carry over. The module snaps onto the breaker's accessory slot — no wiring to the main power path, just the control circuit. Overvoltage category III and a surge voltage resistance of 4 kV mean it's rated for fixed-installation panels with transient exposure, not just clean control-room environments.
Dimensions are 45 mm deep, 62.3 mm wide, and 37.35 mm tall — the module protrudes from the breaker face, so panel depth and door clearance need to account for the rotary operator handle throw.