Schneider Electric Square D QOB320U Circuit Breaker

Schneider Electric Square D QOB320U is a 20-amp, three-pole miniature circuit breaker designed for bolt-on installation in compatible QOB panel interiors, delivering overcurrent protection for 240-volt three-phase circuits. It uses a thermal/magnetic trip mechanism and carries a 10 kA interrupt rating, enabling short-circuit protection for distribution feeders and branch circuits in light commercial and multi-zone installations. The unit includes VisI-Trip indication to show when the breaker has tripped, helping quick status checks during panel maintenance, and its bolt-on design means it mounts directly to the panel without a plug-in connector in panels that support QOB devices. Being part of the Square D QO/QOB family, it shares common trip characteristics and labeling conventions with other QOB breakers. QOB320U is commonly used to protect 3-phase feeders and branch circuits in 240 VAC systems within appropriate panelboards. Like other QOB breakers, the unit is designed to snap into a compatible Square D panelboard and be secured with mounting hardware for a stable installation. Its 20-amp rating suits protection for branch circuits in three-phase systems across light commercial and industrial contexts.