ABB / General Electric THQB2120AF AFCI Miniature Circuit Breaker
- 20A
- 2 Pole
- Bolt-On
Quantity
ABB / General Electric THQB2120AF - 20A AFCI Miniature Circuit Breaker
New
Quantity
Description
Providing essential branch and feeder arc fault mitigation, the GE THQB2120AF supports both residential and commercial electrical systems. This 20-amp, two-pole unit is engineered to mount into GE AQ lighting panels and A-Series panelboards using a secure bolt-on connection. Note that this specific model has been superseded by the THQB2120AF2 combination AFCI, making it ideal for matching existing legacy installations. It features an internal common trip and a 10kAIC rating.Specifications
| Brand | ABB / General Electric |
|---|---|
| Series | THQB |
| Amperage | 20A |
| Poles | 2 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC |
| Frame Type | THQB |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | GE AQ Lighting Panels, GE A-Series Panelboards |
| Wire Gauge | 14-8 AWG (Cu), 12-8 AWG (Al) |
| Max Wire | 8 AWG |
| Min Wire | 14 AWG (Cu), 12 AWG (Al) |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Special Classification | AFCI |
|---|---|
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Padlock Attachment |
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, UL 489, UL 1699 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Internal Common Trip, Quick-Make/Quick-Break |
Product FAQs
6 answersWhich GE panelboards accept the THQB2120AF breaker?
This breaker is engineered specifically for GE AQ Lighting Panels and GE A-Series Panelboards. It requires a bolt-on chassis and will not fit in standard plug-on residential load centers.
What is the difference between THQB and THQL breakers?
THQB breakers, like the THQB2120AF, feature a bolt-on mounting style designed for commercial panelboards. THQL breakers are plug-on units intended for standard residential load centers. They are not interchangeable.
How do I connect the neutral on the THQB2120AF?
This breaker is equipped with a pigtail neutral wire. You must route and terminate this pigtail directly to the neutral bus bar in your panelboard to ensure the arc fault detection circuitry functions correctly.
What wire gauges are approved for the THQB2120AF lugs?
The terminal box lugs accommodate 14 to 8 AWG for copper conductors and 12 to 8 AWG for aluminum conductors. Ensure proper torque specifications are followed during installation.
Why use an AFCI breaker like the THQB2120AF instead of a standard breaker?
While standard breakers only trip during overloads or short circuits, an Arc Fault Circuit Interrupter (AFCI) actively monitors the circuit for dangerous unintended arcing. This provides an essential layer of fire prevention for branch and feeder circuits.
Has the THQB2120AF been replaced by a newer model?
Yes, the THQB2120AF is a legacy branch and feeder AFCI. In many modern applications, it has been superseded by combination AFCI models like the THQB2120AF2, which provide both parallel and series arc detection. However, the THQB2120AF remains suitable for matching existing legacy installations.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 110 reviews.
- SPSarah P.Verified BuyerReviewingABB / General Electric THQB1120 - 20A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/15/26Exactly as Described
These are so hard to find at a good price. Will be ordering again.
- SBSeth B.Verified BuyerReviewingABB / General Electric THQB1120 - 20A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/8/26Hard to find older style breakers
I am pleased to have access to these breakers. We have a number of them at our church. Local suppliers said that they had never seen this kind of breaker. They fit our panel perfectly.
- TZThomas Z.Verified BuyerReviewingABB / General Electric THQB32040 - 40A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/30/26Great company
This company is awesome. Every time I call them and I need help with something. They’re right there to help me. They’re also very knowledgeable. They go out of their way to get you the product that you need right away and not a great price.
- TDTerry D.Verified BuyerReviewingABB / General Electric THQB2130GFT - 30A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/24/2630 AMP GFCI @ POLE
Breakers were new in box as advertised. Good turn around on orders Reasonable pricing much less than abb dealer
- LMLeslie M.Verified BuyerReviewingABB / General Electric THQB21100 - 100A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/16/26Perfect fit.
Always timely with delivery and a perfect.fit.