Eaton / Westinghouse JB3225 Molded Case Circuit Breaker

The JB3225 is designed to mount in legacy Westinghouse panelboards, Eaton Pow-R-Line panelboards, switchboards, and motor control centers. It is a bolt-on, feed-thru breaker that connects directly to the bus structure.

When equipped with standard TA250KB aluminum/copper lugs, the wire connections should be torqued to 275 lb-in. If using T250KB copper-only lugs, torque the connections to 180 lb-in. Always verify the torque specifications printed on the breaker label prior to terminating conductors.

The JB3225 features a fixed thermal element for standard overload protection and an adjustable magnetic element for short-circuit protection. The adjustable magnetic dial allows electricians to fine-tune the instantaneous trip threshold, which helps coordinate with downstream devices and prevents nuisance tripping from high inrush currents during motor startups.

Yes, the JB3225 is an obsolete legacy J-frame breaker originally manufactured by Westinghouse and later by Eaton Cutler-Hammer. It is frequently sourced as a direct replacement to maintain existing infrastructure without the need to retrofit older enclosures.

The JB3225 is a bolt-on breaker that requires direct connection to the panel bus. Ensure the panelboard or switchboard is completely de-energized and follow standard lockout/tagout procedures before attempting installation or maintenance. Verify that the adjustable magnetic trip settings are properly coordinated with the system design to ensure safe fault clearing.