ABB / General Electric THQB2120HID Miniature Circuit Breaker

The HID suffix designates that the breaker is UL listed for High Intensity Discharge lighting. It is engineered to handle the significant current and voltage spikes that occur when gaseous discharge lamps, such as fluorescent and HID lights, are switched on and off, preventing nuisance tripping.

This bolt-on breaker is designed exclusively for commercial and industrial GE A-Series Panelboards and GE AQ Lighting Panels. It will not fit in standard residential Q-Line load centers, which require plug-on THQL or half-inch THQP breakers.

While the standard THQB2120 shares the same physical dimensions, 20A rating, and bolt-on mounting, it lacks the HID rating. If your circuit supplies High Intensity Discharge or fluorescent lighting loads with high inrush currents, you must use the HID-rated version to ensure stable operation and avoid nuisance tripping.

Yes, 15A and 20A HID-rated breakers are SWD (Switching Duty) rated. This means the THQB2120HID is approved to be used as a regular switch for 120V fluorescent lighting loads without degrading the internal breaker mechanism.

No, the THQB2120HID is strictly a thermal-magnetic breaker designed for overcurrent and short-circuit protection. It does not feature Ground Fault Circuit Interrupter (GFCI) or Equipment Protection (GFEP) circuitry.

The bolt-on mounting style secures the breaker directly to the panelboard bus with screws. This creates a rigid, permanent connection that prevents arcing and resists loosening caused by thermal cycling or mechanical vibrations in commercial facilities.