Square D by Schneider Electric QOB290 Circuit Breaker

The Square D by Schneider Electric QOB290 is a bolt-on, 2-pole circuit breaker rated for 90 amps on 120/240 VAC service, designed to protect heavy-duty branch circuits in Square D QO/QOB panelboards. It carries a 10 kA interrupt rating, enabling it to interrupt fault currents up to 10,000 amperes under typical conditions when installed in compatible gear. As a bolt-on QOB device, it mounts in panelboards that employ bolt-on breakers rather than plug-in types, with the two-pole construction disconnecting both hot legs of a 120/240 VAC circuit. Part of the QO/QOB family, the QOB290 supports standard 120/240 VAC operation and is specified for use in panels that accept 90 A bolt-on breakers, making it a common choice for higher-amperage circuits within appropriate Square D installations. With a 120/240 VAC, 2-pole arrangement, it disconnects both hot legs simultaneously, a hallmark of its use in split-phase residential or light commercial panels.