Square D QOB120DF Dual Function Miniature Circuit Breaker
- 20A
- 1 Pole
- Bolt-On
Quantity
Square D QOB120DF - 20A Dual Function Miniature Circuit Breaker
New
Quantity
Description
Built to handle demanding electrical loads, the Square D QOB120DF provides 20 amps of dual function protection. It combines combination arc-fault (CAFCI) and Class A 6mA ground-fault (GFCI) defense into a single device, ideal for residential, commercial, and industrial spaces. This bolt-on breaker mounts into Square D NQ and NQOD panelboards. It features a pigtail neutral connection and pressure plate terminals. Rated 10kAIC at 120VAC, it includes the signature Visi-Trip visual indicator.Specifications
| Brand | Square D |
|---|---|
| Series | QOB |
| Amperage | 20A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120VAC |
| Frame Type | QOB |
|---|---|
| Terminal Type | Pressure Plate |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 14-8 AWG (Al/Cu) |
| Max Wire | 8 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LIG |
| Trip Function | Long-Time, Instantaneous, Ground Fault |
| Trip Adjustability | Fixed |
| Special Classification | Dual Function (AFCI/GFCI) |
|---|---|
| Available Options | Padlock Attachment, Handle Lock |
| Accessories | Pigtail Neutral |
| Standards | UL 489, UL 1699, UL 943, CSA C22.2 No. 5, HACR |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator |
Product FAQs
8 answersCan I install the QOB120DF in a standard QO load center?
No. The QOB120DF is a bolt-on circuit breaker designed specifically for NQ and NQOD panelboards. For a standard residential QO load center, you must use the plug-on equivalent, catalog number QO120DF.
What does Dual Function mean on this Square D breaker?
A dual function circuit breaker combines Combination Arc Fault Circuit Interrupter (CAFCI) and Class A Ground Fault Circuit Interrupter (GFCI) protection into a single device, mitigating both fire and shock hazards.
What is the GFCI trip threshold for the QOB120DF?
This breaker provides Class A ground fault protection, which is designed to trip when it detects a ground fault current of 4 to 6 milliamps to protect personnel from electrical shock.
How is the neutral connected on the QOB120DF?
This breaker features a pigtail neutral connection. The coiled white wire must be routed and secured directly to the panelboard neutral bar for the AFCI and GFCI functions to operate correctly.
Does this breaker require a Plug-on Neutral (PON) panelboard?
No. Because the QOB120DF utilizes a pigtail neutral wire, it is fully compatible with standard, non-PON NQ and NQOD panelboards.
Can I use the QOB120DF on a shared neutral (multi-wire branch circuit)?
No. Single-pole dual function breakers monitor the current balance between the hot and neutral conductors. Sharing a neutral across multiple circuits will cause a current imbalance and result in immediate tripping.
What is the difference between the QOB120DF and the QOB120CAFI?
The QOB120CAFI only provides Combination Arc Fault (CAFCI) protection. The QOB120DF is a Dual Function breaker that provides both CAFCI and Class A GFCI protection in the same unit.
Is there a higher interrupting rating version of this 20A dual function breaker?
Yes. If your panel requires a 22kAIC rating instead of the standard 10kAIC provided by the QOB120DF, you will need to source the QOB120VHDF.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 206 reviews.
- KHKristopher H.Verified BuyerReviewingSquare D QOB120GFI - 20A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/28/26Great Price!
Great price. Fast delivery. My local electric distributor wanted double for the same breaker, so it was a no brainer to order this one. Ordered another one since with the same great service.
- BLBOOSTIX L.Verified BuyerReviewingSquare D QOB220 - 20A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/17/26QOB220
That's nice breakers!
- PHPaul H.Verified BuyerReviewingSquare D QOB330 - 30A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/5/26Quick shipping and delivery
Shipped and delivered on time for installation at one of our projects. Thank you!
- RMRick M.Verified BuyerReviewingSquare D QOB220 - 20A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/3/26Project Mgr
Just what I needed.
- DHDoug H.Verified BuyerReviewingSquare D QOB220 - 20A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/3/26Square D QOB breakers
As always, our order arrived timely, and accurate. You can’t beat their prices that’s why we have used this company for years.