MCCB for line protection with high interrupting capacity
The Siemens SENTRON 3VA1112-5EF32-0CH0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries 125 A continuously up to 50 °C, then derates to 114 A at 70 °C — the full thermal curve is on the nameplate so you can size for the actual cabinet ambient, not just the theoretical maximum. The interrupting ratings are the headline figure here: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 500 V and 690 V. That 187 kA at 240 V means it can safely clear a fault at the service entrance where available fault current is highest — typical for large industrial switchboards or transformer secondaries. The 70 mm depth and 76.2 mm width fit standard SENTRON panel cutouts, so a swap-in replacement for an existing 3VA frame won't require re-drilling the mounting plate.
Built-in undervoltage release and auxiliary switching
This MCCB ships with an undervoltage release (UVR) fitted as the auxiliary release, so it will trip automatically if the control voltage drops below the dropout threshold — common in safety circuits where a loss of control power must open the main breaker. The auxiliary switch block provides 2 auxiliary switches plus 1 trip alarm switch HQ, giving three separate signal paths for status feedback to a PLC or indication lamp. A trip indicator is present on the front face, so a walk-by inspection shows whether the breaker tripped on fault versus being manually opened. The rated insulation voltage is 800 V, which covers 690 V systems with margin. No ground-fault monitoring or communication function is built in — this is a straight line-protection breaker with mechanical auxiliaries, not a smart metering device.