Square D QOU220 Miniature Circuit Breaker

The QOU220 is a unit-mount circuit breaker that can be surface-mounted, flush-mounted, or installed on a standard 35mm DIN rail. Note that mounting feet and DIN rail adapters are typically sold separately.

No. The QOU220 is a unit-mount breaker designed for OEM panels, control panels, and enclosures using cable-in and cable-out connections. Standard QO load centers require plug-on QO breakers, while NQ panelboards use QOB bolt-on breakers.

The QO220 is a plug-on breaker designed exclusively for standard Square D QO load centers. In contrast, the QOU220 is a unit-mount breaker with box lugs on both the line and load sides, intended for independent mounting rather than clipping onto a load center bus bar.

Yes. Because this standard thermal-magnetic QOU breaker does not have designated line and load markings, it can be safely reverse-fed or back-fed in dual power supply applications.

Yes, this breaker is HACR rated, making it suitable for heating, air conditioning, and refrigeration equipment that requires group motor protection.

Yes, 15A and 20A QOU circuit breakers are SWD rated, meaning they are UL Listed for regularly switching 120VAC fluorescent lighting loads.

No. Shunt trips and auxiliary switches for standard QOU circuit breakers must be factory-installed. You need to order a specific catalog number with the appropriate accessory suffix (such as 1021 for a 120V shunt trip), as these internal accessories cannot be added in the field.

Yes, the QOU220 includes Square D's Visi-Trip indicator. When the breaker trips due to an overcurrent or short circuit, a highly visible red indicator appears, allowing for quick identification of the faulted circuit in a busy control panel.