Eaton / Westinghouse LA3350PR Molded Case Circuit Breaker

The LA3350PR is a unit-mount, bolt-on breaker designed for legacy Westinghouse panelboards and switchboards. It is specifically used in systems requiring high interrupting capacity L-frame breakers.

The PR suffix designates this as a Tri-Pac current-limiting circuit breaker. It utilizes integrally fused protection to safely interrupt extremely high fault currents, achieving a 200kAIC rating at up to 600VAC.

The breaker provides a fixed thermal element for standard long-time overload protection. The magnetic instantaneous trip is adjustable, allowing panel builders to fine-tune the short-circuit response to coordinate with downstream devices and prevent nuisance tripping.

Yes, the factory lugs support dual-wire terminations. You can land two 1 AWG to 250 kcmil conductors per phase, or a single 1 AWG to 600 kcmil conductor per phase, using either copper or aluminum wire.

Yes, the LA3350PR shares the standard Westinghouse L-frame footprint but includes built-in current limiters. It serves as a direct bolt-on replacement for standard LA3350 breakers when upgrading a system to handle higher fault currents.

The integral fuses in the Tri-Pac design clear severe short circuits faster than standard mechanical contacts. This drastically reduces the peak let-through current and thermal energy, preventing catastrophic damage to downstream components during a major fault.