The Siemens 3VA9988-0AB33 is a SENTRON short-circuit signaling switch — an accessory for 3VA circuit breakers that provides a remote indication when the breaker trips on a short circuit. It fits the 3VA1 160 frame. The switch occupies a single 7 mm slot on the DIN rail, so it adds a signaling point without eating up multiple module positions in the panel.
What the ratings mean for fit
Rated insulation voltage (Ui) is 690 V, and the rated impulse withstand voltage is 4 kV. Overvoltage category III and pollution degree 3 suit fixed-installation environments inside industrial enclosures. The thermal current limit Ith is 0.3 A, which is the continuous carry rating of the contacts. For switching duty, the ratings break down by load type: AC-12 and AC-15 at 12 V or 24 V are 0.3 A; DC-12 at 12 V or 24 V is 0.1 A; DC-13 (solenoid / relay loads) at 12 V or 24 V is 0.07 A. If the load is a DC relay coil, the 0.07 A DC-13 figure is the one that governs the real use — not the higher AC number. The switch provides a changeover contact (HQ type), so it can be wired to signal both the normal and tripped state to a PLC or indicator lamp.
Panel integration
Mounts on the DIN rail alongside the 3VA breaker it signals. Width is 7 mm (one slot), depth 30 mm, height 56 mm. Wire stripping length is 15 mm (0.6 in) for the screw terminals.