Zinsco RC38-1520 15/20A Tandem Miniature Circuit Breaker

This plug-on breaker is designed specifically for legacy Zinsco, GTE Sylvania, and Challenger load centers that use the Zinsco bus bar design. It is not interchangeable with standard one-inch breakers from other brands.

Connecticut Electric manufactures a direct replacement for this model under the catalog number UBIZ1520. The UBIZ1520 is UL listed for use in original Zinsco load centers and serves as a modern substitute.

This twin breaker houses two independent thermal-magnetic trip mechanisms (one 15 Amp and one 20 Amp) within a standard single-pole footprint. This allows you to add an additional circuit to a fully populated panel without requiring a subpanel.

No. The RC38-1520 is a tandem breaker that mounts to a single bus bar stab, providing two independent 120V circuits on the same phase. It cannot supply 240V power and should not be used for multi-wire branch circuits sharing a neutral.

The box lugs accept 14 AWG to 10 AWG copper or aluminum wire. When wiring this tandem unit, ensure you use appropriately sized conductors for each independent circuit, typically 14 AWG for the 15 Amp side and 12 AWG for the 20 Amp side.

Zinsco bus bars are highly susceptible to corrosion and arcing damage. Before installing the RC38-1520, thoroughly inspect the panel bus stabs for pitting, burn marks, or degradation. If the bus bar is damaged, the entire panel may require replacement to ensure safety.