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Square D QOB345 Miniature Circuit Breaker
- 45A
- 3 Pole
- Bolt-On
Square D
QOB345
Miniature Circuit Breaker
Brand
Square D
SKU
QOB345
Quantity
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Square D QOB345 - 45A 3 Pole Miniature Circuit Breaker
New
Quantity
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Square D QOB345 - 45A 3 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOB345 |
| Series | QOB |
| Amperage | 45A |
| 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 | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Cu/Al) |
| 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 | HACR, UL 489, CSA C22.2 No. 5 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
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Square D QOB345 - 45A 3 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOB345-R |
| Series | QOB |
| Amperage | 45A |
| 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 | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Cu/Al) |
| 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 | HACR, UL 489, CSA C22.2 No. 5 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
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Description
Built for commercial systems, the QOB345 delivers 45 amps of thermal-magnetic protection. This three-pole breaker ensures consistent performance across 240V applications. Installation is straightforward with a secure bolt-on mounting style. It integrates seamlessly into Square D NQ and NQOD panelboards, accommodating 8-2 AWG wiring. A standout feature is the signature Visi-Trip indicator, providing immediate visual confirmation of a tripped circuit. It carries a standard 10kAIC rating.Specifications
| Brand | Square D |
|---|---|
| Part Number | QOB345 |
| Series | QOB |
| Amperage | 45A |
| 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 | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Cu/Al) |
| 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 | HACR, UL 489, CSA C22.2 No. 5 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Product FAQs
7 answersWhat panelboards are compatible with the Square D QOB345?
The QOB345 features a bolt-on mounting mechanism designed specifically for Square D NQ panelboards and legacy NQOD panelboards. It will not fit in standard QO load centers.
Can I install the QOB345 in a residential QO load center?
No. The QOB345 is a commercial bolt-on breaker. For a standard Square D QO load center, you must use the plug-on equivalent, catalog number QO345.
Does the QOB345 carry a DC voltage rating?
Yes, this breaker is rated for use on DC systems up to 48VDC, where it provides an interrupting rating of 5kAIC. This makes it suitable for specific battery or control panel applications.
How many panel spaces does this three-pole breaker occupy?
The QOB345 requires three standard 0.75-inch pole spaces in an NQ or NQOD panelboard, taking up a total width of 2.25 inches.
Are the lugs on the QOB345 rated for aluminum wire?
Yes, the factory-installed box lugs are dual-rated for both copper and aluminum (Cu/Al) conductors ranging from 8 AWG up to 2 AWG.
How does the QOB345 indicate a tripped condition?
This breaker includes Square D Visi-Trip technology. When a fault causes the breaker to trip, the handle moves to a center position and a bright red indicator appears in the window on the faceplate to help quickly locate the tripped circuit.
Is the QOB345 suitable for HVAC equipment?
Yes, the QOB345 is HACR rated, meaning it is certified for use with heating, air conditioning, and refrigeration equipment requiring a 45-amp, three-pole protective device.
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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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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 211 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
211 reviews
- MLMike L.Verified BuyerReviewingSquare D QOB250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/9/26breaker orders
Breaker worked out great
Can not be happier with the quick shipping
- RCRichard C.Verified BuyerReviewingSquare D QOB380 - 80A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/7/26Great price quick turn around
Thank you for getting me the breaker in a timely fashion
- DSDarren S.Verified BuyerReviewingSquare D QOB250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/5/26Airport taxi lighting
After contactor replacement we discovered bad breakers and were able to get replacements from Super Breakers in 2 days. THANK YOU SUPER BREAKERS..
- MRMiguel R.Verified BuyerReviewingSquare D QOB220GFI - 20A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/1/26Excellent
Excellent product and service
- MRMiguel R.Verified BuyerReviewingSquare D QOB230GFI - 30A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/1/26Excellent
Excellent product and service