ABB / General Electric THHQB1115GFT GFCI Miniature Circuit Breaker

This bolt-on breaker is designed specifically for installation in GE A-Series and ReliaGear RQ panelboards. It will not fit in standard residential plug-on load centers.

Yes, it serves as a direct drop-in replacement for the discontinued THHQB1115GF model. The added T in the catalog number indicates an integrated self-test feature, which meets updated NEC requirements for GFCI devices.

The difference lies in the short-circuit interrupting rating. The standard THQB1115GFT is rated for 10kAIC, while the THHQB1115GFT provides a higher interrupting capacity of 22kAIC. Both share the same physical dimensions and bolt-on mounting configuration.

It provides Class A ground fault protection, designed to trip when current leakage to ground reaches 5mA. This protects personnel from electrical shock in wet or damp locations.

The breaker is equipped with a factory-installed pigtail neutral wire. This pigtail must be routed and terminated directly to the neutral bus bar in the panelboard to power the internal ground fault circuitry.

No. Class A GFCI breakers require a dedicated neutral for the protected circuit. If the neutral is shared with another circuit, the breaker will detect an imbalance and trip immediately.

The built-in self-test mechanism automatically performs periodic internal diagnostics to verify that the ground fault detection circuitry is working properly. This ensures continuous personnel protection in compliance with UL standards.