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Square D QO345 Miniature Circuit Breaker
- 45A
- 3 Pole
- Plug-On
Square D
QO345
Miniature Circuit Breaker
Brand
Square D
SKU
QO345
Quantity
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Square D QO345 - 45A 3 Pole Miniature Circuit Breaker
New
Quantity
Quantity
Square D QO345 - 45A 3 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | QO345 |
| Series | QO |
| Amperage | 45A |
| Poles | 3 |
| Mounting Style | Plug-On |
| Voltage | 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QO |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | QO Load Centers, NQ Panelboards, NQOD Panelboards, Speed-D Switchboards |
| 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 | Padlock Attachment |
|---|---|
| Standards | CSA C22.2 No. 5, UL 489, HACR, NEMA AB 1 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Sold out
Quantity
Square D QO345 - 45A 3 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | QO345-R |
| Series | QO |
| Amperage | 45A |
| Poles | 3 |
| Mounting Style | Plug-On |
| Voltage | 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QO |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | QO Load Centers, NQ Panelboards, NQOD Panelboards, Speed-D Switchboards |
| 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 | Padlock Attachment |
|---|---|
| Standards | CSA C22.2 No. 5, UL 489, HACR, NEMA AB 1 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
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Description
Engineered for seamless integration into QO load centers, NQ, and NQOD panelboards, the Square D QO345 provides robust overcurrent protection. This 3-pole, 45A miniature circuit breaker utilizes thermal-magnetic trip technology to safeguard electrical systems across residential, commercial, and industrial applications. Rated at 10 kAIC at 240VAC, it features the signature Visi-Trip visual indicator, allowing users to instantly spot a tripped circuit. HACR rated for HVAC equipment.Specifications
| Brand | Square D |
|---|---|
| Part Number | QO345 |
| Series | QO |
| Amperage | 45A |
| Poles | 3 |
| Mounting Style | Plug-On |
| Voltage | 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QO |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | QO Load Centers, NQ Panelboards, NQOD Panelboards, Speed-D Switchboards |
| 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 | Padlock Attachment |
|---|---|
| Standards | CSA C22.2 No. 5, UL 489, HACR, NEMA AB 1 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Product FAQs
7 answersCan I install the QO345 in a Square D NQ or NQOD panelboard?
Yes, the plug-in QO345 is compatible with NQ and NQOD panelboards, as well as standard QO load centers and Speed-D switchboards. If your specific panel interior requires bolt-on connections, you must use the QOB345 instead.
What is the recommended lug torque for the QO345 circuit breaker?
The box lugs on the QO345 should be torqued to 44.3 lb-in (5 N.m) for both copper and aluminum wiring.
Is there a bolt-on equivalent for the QO345?
Yes, the bolt-on equivalent is the Square D QOB345. It shares the same electrical ratings but features mounting brackets for bolt-on panelboard interiors.
Is the QO345 HACR rated for HVAC applications?
Yes, this breaker is HACR rated, making it suitable for use with heating, air conditioning, and refrigeration equipment that requires this specific rating.
How does the QO345 indicate a tripped condition?
The breaker features the Square D Visi-Trip indicator. When the breaker trips due to an overcurrent or short circuit, the handle moves to a center position and a highly visible red indicator flag appears in the window.
Can the QO345 be used in DC voltage applications?
Yes, in addition to its standard AC ratings, the QO345 is rated for 48VDC applications with a 5kA interrupting capacity.
Does the QO345 require a neutral connection for installation?
No, the QO345 is a standard thermal-magnetic breaker. It does not feature a neutral pigtail or plug-on neutral clip, as it is designed strictly for 3-phase, 3-wire applications.
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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 285 reviews.
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 6/13/26
Customers say these circuit breakers arrive quickly and work as described. Fast shipping and competitive pricing are frequently mentioned, with many noting same-day or next-day delivery. Users appreciate the wide inventory, particularly for hard-to-find older-style models unavailable locally. The products function reliably and arrive in good condition. Most customers report straightforward ordering and positive interactions. However, some experienced delivery delays or received incorrect items requiring reordering. A few noted concerns about condition upon arrival or customer service responsiveness.
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Rating
285 reviews
- GCGerard C.Verified BuyerReviewingSquare D QO130GFI - 30A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/21/26Great !
I could not find the breaker in hardwood stores. Superbreakers took car of it in a week.
- RHRoy H.Verified BuyerReviewingSquare D QO280 - 80A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/17/26Square D QO280 - 80A 2 Pole Miniature Circuit Breaker
Exactly as described
- KWKevin W.Verified BuyerReviewingSquare D QO120 - 20A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/15/26Great Price
Brand spanking new!
- CEchristopher e.Verified BuyerReviewingSquare D QO115PDF - 15A Dual Function Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/11/26My breakers
Had a hard time locating these breakers locally, when I did find 1 they wanted to charge me triple what superbreakers charged. Items delivered exactly when they said they would, were exactly what I ordered. Appreciated the ease of ordering, definitely my go to from this point on
- JCJerry C.Verified BuyerReviewingSquare D QO250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/8/26Great quality
No issues