Schneider Electric QOB320 Thermal Magnetic Circuit Breaker

Schneider Electric's Square D QOB320 is a three‑pole, bolt‑on miniature circuit breaker designed for reliable overcurrent protection in panels and switchboards. It is a 20 A device suitable for 120/240 VAC service, employing thermal‑magnetic trip protection to handle both overloads and short circuits with common trip across all poles. The unit carries a 10 kA interrupting rating at 120/240 VAC (UL/CSA) and accepts 14–8 AWG copper or aluminum conductors, making it versatile for residential, commercial, or light‑industrial feeders. Its compact bolt‑on footprint enables straightforward replacement in standard enclosures, with a width of about 2.25 in, and it is part of Schneider Electric’s QOB family, delivering UL/CSA‑listed, three‑pole protection for multiwire circuits, including a 48 VDC rating listed on some product listings.