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Square D QOB320 Miniature Circuit Breaker
- 20A
- 3 Pole
- Bolt-On
Square D
QOB320
Miniature Circuit Breaker
Brand
Square D
SKU
QOB320
Quantity
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Square D QOB320 - 20A 3 Pole Miniature Circuit Breaker
New
Quantity
Quantity
Square D QOB320 - 20A 3 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOB320 |
| Series | QOB |
| Amperage | 20A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC, 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 120VAC, 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| 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 | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | UL 489, CSA C22.2 No. 5, HACR |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Quantity
Square D QOB320 - 20A 3 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOB320-R |
| Series | QOB |
| Amperage | 20A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC, 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 120VAC, 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| 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 | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | UL 489, CSA C22.2 No. 5, HACR |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
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Description
Built to handle standard commercial loads, this 20-amp, three-pole unit offers reliable thermal-magnetic protection with a 10kA interrupting capacity. The robust construction includes the signature Visi-Trip indicator, allowing maintenance personnel to quickly spot tripped circuits. It fastens securely into Square D NQ and NQOD panelboards via a sturdy bolt-on connection. This HACR-rated component is suitable for heating, air conditioning, and refrigeration equipment circuits.Specifications
| Brand | Square D |
|---|---|
| Part Number | QOB320 |
| Series | QOB |
| Amperage | 20A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC, 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 120VAC, 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| 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 | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | UL 489, CSA C22.2 No. 5, HACR |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Product FAQs
7 answersCan I install the QOB320 in a standard Square D residential load center?
No. The QOB320 is a bolt-on breaker designed exclusively for commercial NQ and NQOD panelboards. Standard residential load centers require plug-on QO series breakers.
Are the QOB320 and QO320 interchangeable?
No. While both are 3-pole, 20-amp breakers with identical thermal-magnetic trip characteristics, the QOB320 mounts via a bolted connection. The QO320 snaps into place and is used in plug-on load centers. You must match the mounting style exactly to your panel's requirements.
How does the QOB320 connect to the panelboard bus?
It uses a captive screw to bolt directly to the panelboard busbar. This permanent connection method ensures a tight, reliable fit that resists loosening in commercial and industrial environments where vibration is common.
Is this circuit breaker HACR rated?
Yes, the QOB320 carries an HACR rating, making it approved for use with heating, air conditioning, and refrigeration equipment that requires group motor protection.
Can I use the QOB320 for switching fluorescent lighting circuits?
No, this 3-pole breaker does not carry a Switching Duty (SWD) rating. SWD ratings are specifically limited to 15-amp and 20-amp single-pole QO and QOB circuit breakers.
Does the QOB320 feature a tripped circuit indicator?
Yes, it includes Square D's Visi-Trip technology. When an overcurrent or short circuit causes the breaker to trip, the handle rests in a center position and a bright red flag appears in the indicator window, allowing electricians to quickly identify the faulted circuit.
Does a fault on one phase trip all three poles?
Yes, the QOB320 utilizes a common trip mechanism. If an overload or short circuit occurs on any single phase, the internal trip bar simultaneously opens all three poles to prevent dangerous single-phasing of three-phase equipment.
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Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.
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All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.
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