Zinsco QCAL-20 U Molded Case Circuit Breaker

The Zinsco QCAL-20 U is a 20 Amp, 2-pole molded‑case circuit breaker designed for use in Zinsco / GTE Sylvania load centers. It operates on 240V systems and uses a thermal‑magnetic trip to protect circuits from overloads and short circuits. This plug‑in (snap‑in) breaker belongs to the QC/QCAL series and is rated for about 10 kAIC at 240V, providing overcurrent and short‑circuit protection for 2‑pole circuits. Common applications include residential and light commercial 240V branch circuits such as small air conditioners, pumps, water heaters, and dedicated appliance loads requiring 20A protection; it is intended for legacy Zinsco panels and is typically used for maintenance or replacement of existing systems. The QCAL‑20 U is obsolete/discontinued, available in surplus or aftermarket channels. Common replacements include Connecticut Electric UBIZ220 2‑Pole 20A, Siemens Q220 2‑Pole 20A, and Square D HOM220 / QO220 2‑Pole 20A circuit breakers.