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Free Shipping Over $99
Free Shipping Over $99
Free Shipping Over $99
Square D QOB150 Miniature Circuit Breaker
- 50A
- 1 Pole
- Bolt-On
Square D
QOB150
Miniature Circuit Breaker
Brand
Square D
SKU
QOB150
Quantity
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Square D QOB150 - 50A 1 Pole Miniature Circuit Breaker
New
Quantity
Quantity
Square D QOB150 - 50A 1 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOB150 |
| Series | QOB |
| Amperage | 50A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC, 48VDC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOB |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 8 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 | CSA C22.2 No. 5, UL 489, HACR |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Quantity
Square D QOB150 - 50A 1 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOB150-R |
| Series | QOB |
| Amperage | 50A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC, 48VDC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOB |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 8 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 | CSA C22.2 No. 5, UL 489, HACR |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
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Description
Providing robust electrical safety, the Square D QOB150 is a 50A, 1-pole miniature circuit breaker. It is engineered for heavy-duty commercial and industrial applications requiring consistent thermal-magnetic protection. This unit is specifically manufactured to mount into Square D NQ and NQOD panelboards. Its bolt-on terminal design ensures a permanent, high-integrity connection that prevents arcing and withstands mechanical stress. With a 10 kAIC capacity, it is HACR rated for HVAC loads.Specifications
| Brand | Square D |
|---|---|
| Part Number | QOB150 |
| Series | QOB |
| Amperage | 50A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120/240VAC, 48VDC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOB |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 8 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 | CSA C22.2 No. 5, UL 489, HACR |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Product FAQs
5 answersWhich panelboards are compatible with the QOB150 circuit breaker?
The QOB150 is a bolt-on breaker designed specifically for Square D NQ and NQOD panelboards. It cannot be installed in standard QO load centers, which require plug-on breakers.
What is the plug-on equivalent for the QOB150?
If you are installing a 50A, 1-pole breaker in a standard Square D QO load center rather than a bolt-on panelboard, the correct plug-on equivalent is catalog number QO150.
What wire sizes does the QOB150 accept, and what is the recommended torque?
The box lugs on this breaker accept 8 AWG to 2 AWG aluminum or copper wire. The recommended tightening torque for the terminals is 44.3 lb-in.
Can the QOB150 be used in DC power systems?
Yes, in addition to its standard AC ratings, this breaker is rated for DC applications up to 48VDC with an interrupting capacity of 5kAIC.
Does the QOB150 feature a Visi-Trip indicator?
Yes, this breaker includes the Square D Visi-Trip indicator. It displays a highly visible red flag when the breaker has tripped, allowing for rapid identification of a faulted circuit within the panelboard.
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Free Shipping Policy
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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We strive to ship out your items the same day the order is placed. In rare circumstances SuperBreakers may reserve up to 5 business days to consolidate orders for complete shipment.
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Orders being shipped via Next Day Air, 2 Day Shipping or 3 Day Shipping must be received by 3 PM EST to guarantee same-day shipments. Expedited orders only ship on normal business days. Shipments will NOT be sent out on Saturdays and Sundays.
International Shipping
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