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Square D QOB120AS Miniature Circuit Breaker
- 20A
- 1 Pole
- Bolt-On
Square D
QOB120AS
Miniature Circuit Breaker
Brand
Square D
SKU
QOB120AS
Quantity
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Square D QOB120AS - 20A 1 Pole Miniature Circuit Breaker
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Description
Integrating automated control into standard power distribution, this 20-amp single-pole device handles remote switching tasks for commercial facilities. It installs seamlessly into Square D Powerlink, NQ, and NQOD panelboards, serving as a functional substitute for the QOB120ASB. Rated for 10kAIC at 120/240VAC, the unit combines standard thermal-magnetic protection with Switching Duty approval and a Visi-Trip flag.Specifications
| Brand | Square D |
|---|---|
| Part Number | QOB120AS |
| Series | QOB |
| Amperage | 20A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC |
| Frame Type | QOB |
|---|---|
| Terminal Type | Pressure Plate |
| For Use With | NQ Panelboards, NQOD Panelboards, Powerlink Panelboards |
| Wire Gauge | 14-8 AWG (Al/Cu) |
| Max Wire | 8 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Alarm Switch, Handle Padlock Attachment, Shunt Trip |
|---|---|
| Accessories | Auxiliary Switch (Factory Installed), Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, UL 489, NEMA AB 1 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, SWD Rated, Visual Trip Indicator |
| Special Features | Remotely Operated |
Product FAQs
7 answersWhich panelboards accept the QOB120AS circuit breaker?
This bolt-on breaker is designed specifically for Square D NQ, NQOD, and Powerlink panelboards. It cannot be installed in standard QO or Homeline plug-on load centers.
What is the difference between QO and QOB circuit breakers?
QO breakers are plug-on devices designed for residential QO load centers, while QOB breakers like the QOB120AS feature a bolt-on connection for secure installation in commercial NQ and NQOD panelboards.
What does the AS suffix indicate on the QOB120AS?
The AS suffix designates this as a Powerlink AS remotely operated circuit breaker. It is engineered for automated control and remote switching applications in commercial facilities.
Is the QOB120AS a direct replacement for the QOB120ASB?
Yes, the QOB120AS serves as a functional substitute for the QOB120ASB when used in compatible Powerlink, NQ, or NQOD panelboards.
How does the QOB120AS indicate a tripped condition?
It features the Square D Visi-Trip indicator. When the breaker trips due to an overload or short circuit, a highly visible red flag appears in the indicator window for rapid identification in a crowded panel.
Does the QOB120AS feature Qwik-Open technology?
Yes, as a 1-pole 20A breaker in the QO and QOB family, it includes Square D's Qwik-Open mechanism. This feature is designed to trip within 1/60th of a second under severe short-circuit conditions.
How does the thermal-magnetic trip mechanism operate on this breaker?
The fixed thermal-magnetic mechanism uses a long-time function to handle mild, prolonged overloads and an instantaneous function to immediately clear severe short circuits.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 205 reviews.
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 3/11/26
Customers say these electrical breakers arrive exactly as ordered and work perfectly for their intended applications. They consistently praise the competitive pricing, which many report is significantly lower than local suppliers. Fast shipping and prompt delivery are frequently highlighted, with many receiving orders within days or even next-day delivery for urgent needs. The breakers arrive well-packaged and in excellent condition. Many reviews emphasize the company's extensive inventory availability, particularly for hard-to-find breakers. One customer experienced difficulty with order cancellation and was charged a restocking fee, which caused dissatisfaction.
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Rating
205 reviews
- 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.
- RKRyan K.Verified BuyerReviewingSquare D QOB230VH - 30A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/1/26Awesome
Worked great