The LV839256 is an XF closing voltage release for MasterPact MTZ drawout circuit breakers. It operates the closing mechanism when the control circuit is energized, with a threshold tripping voltage of 0.85 to 1.1 Un. Holding power draws 4.5 VA / 4.5 W once the coil is sealed. This is a drawout-mounted accessory — it plugs into the breaker cradle, not hard-wired into the panel.
Response time varies by breaker frame: 55 ms ±10% for MasterPact MTZ1, 70 ms ±10% for MTZ2, and 80 ms ±10% for MTZ3. That spread matters for coordination studies — if you are sequencing multiple breakers, the MTZ3's longer close time may shift your intentional delay window. The drawout mounting means the coil stays with the cradle, not the moving breaker; swap a breaker without disturbing the control wiring.