Eaton / Cutler-Hammer QBHW2050S Miniature Circuit Breaker

The "S" suffix designates that this breaker is equipped with a factory-installed shunt trip. This allows the breaker to be tripped remotely by applying a voltage signal, which is frequently used for emergency shutdown systems or automated control circuits.

This Quicklag bolt-on breaker is designed for installation in Eaton Pow-R-Line panelboards, as well as legacy Westinghouse panelboards that accept BAB or QBHW frame breakers.

Both series share the same physical dimensions and bolt-on mounting style for Pow-R-Line panelboards. The difference lies in their short-circuit interrupting ratings. BAB breakers are rated for 10kAIC, whereas the QBHW series provides a higher interrupting capacity of 22kAIC at 120/240VAC.

It utilizes a bolt-on connection, meaning the breaker is physically bolted directly to the panelboard busbars. This creates a highly secure, vibration-resistant electrical connection that is standard in commercial and industrial distribution panels.

The fixed thermal-magnetic mechanism provides two types of protection. The thermal element responds to sustained overloads by heating up and tripping the breaker after a delay, while the magnetic element provides instantaneous tripping when it detects high-fault short-circuit currents.

Yes, it will physically fit and provide the same 50A overcurrent protection. However, the QBHW2050S includes a shunt trip for remote disconnect applications. If your system does not require remote tripping, the standard QBHW2050 is the direct equivalent without the shunt trip feature.