The LV847439 is an XF closing voltage release — the solenoid that closes the MasterPact MTZ1 drawout breaker when 12 VDC is applied to the coil. It's a standard-control accessory, not the undervoltage or shunt-trip variant, so it only fires on a deliberate close command, not on voltage recovery. The coil holds at 4.5 W and closes within 65 ms on an MTZ1 frame. The operating threshold is 0.85 to 1.1 times the rated Un (12 VDC), meaning the breaker will close reliably as long as the control supply stays above about 10.2 V and below 13.2 V.
Sourcing Reality — Obsolete, but Findable
Schneider lists the LV847439 as obsolete. No direct successor order code is published in the available records, so there's no drop-in factory replacement to cross-reference.