The Schneider Electric LV833791 is an MX opening voltage release with diagnostics and communication, part of the MasterPact range for MTZ1 drawout circuit breakers. It's a control component that trips the breaker on command or on loss of supply voltage — the signalling function covers electrical push-button activated Ready to close, open, coil powered, and error states. Rated for a 12 V DC supply with a holding power consumption of 4.5 W, it responds within 60 ms on opening for MasterPact MTZ1. The tripping voltage threshold spans 0.7 to 1.1 Un on opening, so it releases reliably even if the control voltage sags.
The 12 V DC supply is the critical fit parameter — this is a low-voltage control coil, not a 24 V or 48 V unit common in many panels. If your MTZ1 drawout breaker uses a 12 V DC control scheme, this matches. Drawout mounting means this voltage release installs into the breaker's removable cradle, not a fixed panel location. The 60 ms maximum response time on opening is fast enough for most protection schemes — it clears a fault or initiates a controlled shutdown within one power cycle at 50 Hz.