The LV839337 is a MasterPact MTZ3 cradle — the stationary chassis that receives the drawout breaker mechanism. It is rated for 4000 to 6000 A at 104 °F (40 °C), 4-pole configuration, and carries UL/ANSI listing for North American installations. The drawout mounting mode means the breaker unit slides into this cradle on rails, allowing the breaker to be racked to the disconnected, test, or connected position without unbolting power conductors.
Integration notes for the switchgear lineup
The cradle accepts the MTZ3 drawout breaker and provides the primary disconnect stabs, secondary control wiring contacts, and racking mechanism. The 4-pole configuration supports three-phase-plus-neutral or three-phase-plus-switched-pole applications. Rated operational current of 4000-6000 A at 40 °C sets the continuous current capacity of the cradle assembly — the breaker inserted into it must be rated for the same or lower current to maintain coordination.