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Square D QOU240 Miniature Circuit Breaker
- 40A
- 2 Pole
- Unit Mount
Square D
QOU240
Miniature Circuit Breaker
Brand
Square D
SKU
QOU240
Quantity
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Square D QOU240 - 40A 2 Pole Miniature Circuit Breaker
New
Quantity
Quantity
Square D QOU240 - 40A 2 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOU240 |
| Series | QOU |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | Unit Mount |
| Voltage | 120/240VAC, 48VDC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOU |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | DIN Rail Systems, OEM Panels, Enclosures, Control Panels |
| Wire Gauge | 14-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Mounting Feet, Padlock Attachment |
|---|---|
| Accessories | Line and Load Lugs Included |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, HACR, IEC, RoHS, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Common Trip |
Sold out
Quantity
Square D QOU240 - 40A 2 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | QOU240-R |
| Series | QOU |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | Unit Mount |
| Voltage | 120/240VAC, 48VDC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOU |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | DIN Rail Systems, OEM Panels, Enclosures, Control Panels |
| Wire Gauge | 14-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Mounting Feet, Padlock Attachment |
|---|---|
| Accessories | Line and Load Lugs Included |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, HACR, IEC, RoHS, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Common Trip |
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Description
Built for versatile applications, this 40A, two-pole miniature circuit breaker delivers reliable thermal-magnetic protection. It is HACR rated for HVAC equipment. The unit-mount design allows for seamless installation into OEM panels, enclosures, and DIN rail systems. Reversible box lugs accept 14-2 AWG wiring. With a 10kAIC rating at 120/240VAC, it safely interrupts faults. The Visi-Trip window shows a red indicator when tripped, helping users quickly restore power.Specifications
| Brand | Square D |
|---|---|
| Part Number | QOU240 |
| Series | QOU |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | Unit Mount |
| Voltage | 120/240VAC, 48VDC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOU |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | DIN Rail Systems, OEM Panels, Enclosures, Control Panels |
| Wire Gauge | 14-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Mounting Feet, Padlock Attachment |
|---|---|
| Accessories | Line and Load Lugs Included |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, HACR, IEC, RoHS, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Common Trip |
Product FAQs
5 answersCan I install the QOU240 in a standard Square D QO load center?
No. While it is part of the QO family, this is a unit-mount circuit breaker built for OEM panels, DIN rails, and standalone enclosures. Standard QO load centers require plug-on style breakers.
How do you mount this miniature circuit breaker?
It can be surface or flush mounted directly to a backpan using its built-in mounting feet, or it can be snapped onto a standard 35mm DIN rail using compatible DIN rail adapter clips.
What is the required tightening torque for the terminals?
The manufacturer specifies a tightening torque of 45 lb-in (5.08 N.m) for both the line and load side box lugs when using 14-2 AWG aluminum or copper wire.
Is the QOU240 approved for use with HVAC equipment?
Yes, it is HACR rated, meaning it is specifically approved for the demands of heating, air conditioning, and refrigeration equipment. It also carries a Switching Duty (SWD) rating.
Does this breaker provide a visual tripped indication?
Yes, it features the Square D Visi-Trip indicator. A bright red flag appears in the breaker window when it trips, allowing personnel to rapidly identify the faulted circuit.
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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 5.0 out of 5 based on 106 reviews.
Reviews Summary
Generated by AI from 99 most recent customer reviews
Last updated 5/14/26
Customers say these circuit breakers function properly and arrive quickly. Many reviews highlight fast shipping, competitive pricing, and reliable product condition upon arrival. Users appreciate the wide selection, including hard-to-find models, and note the breakers work as expected for various applications. Common feedback addresses quick order processing and easy website navigation. Most customers report satisfaction with value and delivery speed, with many indicating they will purchase again.
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Rating
106 reviews
- HLHOMETIGO L.Verified BuyerReviewingSquare D QOU260 - 60A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/7/26Good thing
i recommend this for you
- RGRobert G.Verified BuyerReviewingSquare D QOU340 - 40A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/3/26Circuit breakers
I appreciate the fact that you had these in stock. my Square D distributor does not seem to stock these anymore and it takes a couple weeks to get. your pricing is inline with theirs.
- THTiffany H.Verified BuyerReviewingSquare D QOU115 - 15A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/28/26Will use Super Breakers again
Arrived in a timely manner. Exactly what we needed for a job.
- CSCary S.Verified BuyerReviewingSquare D QOU250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/12/26Just what I ordered
Just what I needed for dock pedestal
- MHMark H.Verified BuyerReviewingSquare D QOU250VH - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/11/26Square D QOU250VH - 50A 2 Pole Miniature Circuit Breaker
Was just what I expected!