ABB / General Electric THQL2120GFT GFCI Miniature Circuit Breaker

The THQL2120GFT is the direct, drop-in replacement for the obsolete THQL2120GF. The "T" suffix designates the addition of an automatic self-test feature, which periodically checks the internal ground-fault detection circuitry to ensure ongoing compliance with updated NEC safety standards.

This Q-Line breaker is designed exclusively for use in GE PowerMark Gold and ABB ReliaHome load centers that accept 1-inch plug-in breakers. It is not interchangeable with other panel brands.

It provides Class A ground-fault protection, meaning it is calibrated to trip when it detects a ground-fault current of 5mA. This level of sensitivity is required for personnel protection in wet or damp locations like bathrooms, kitchens, and outdoor receptacles.

This breaker features a standard pigtail neutral. The coiled white pigtail wire must be connected directly to the neutral bus bar in the load center to power the breaker's internal ground-fault circuitry, while the load neutral connects directly to the breaker terminal.

Yes, a 2-pole GFCI breaker like the THQL2120GFT can be used to protect 120/240V multi-wire branch circuits (shared neutral circuits) or dedicated 240V loads, provided the load neutral is properly routed to the breaker.

The LIG designation means the breaker provides Long-Time (thermal overload), Instantaneous (magnetic short-circuit), and Ground-Fault protection. This combination ensures comprehensive defense against overcurrents, short circuits, and ground faults in a single device.