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Square D QO2401021 Miniature Circuit Breaker
- 40A
- 2 Pole
- Plug-On
Square D
QO2401021
Miniature Circuit Breaker
Brand
Square D
SKU
QO2401021
Quantity
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Square D QO2401021 - 40A 2 Pole Miniature Circuit Breaker
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Description
Engineered for commercial and industrial applications, the Square D QO2401021 delivers reliable 40A thermal-magnetic protection. This two-pole miniature circuit breaker features a Visi-Trip indicator for quick fault identification. It mounts into standard QO load centers, as well as NQ and NQOD panelboards. The integrated 120/208/240VAC shunt trip mechanism allows facility managers to remotely open the circuit for emergency shutdowns or automated control systems.Specifications
| Brand | Square D |
|---|---|
| Part Number | QO2401021 |
| Series | QO |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | Plug-On |
| Voltage | 120/240VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120/240VAC |
| Frame Type | QO |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | QO Load Centers, 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 | Padlock Attachment |
|---|---|
| Accessories | Shunt Trip |
| Standards | CSA C22.2 No. 5, UL 489, HACR, NEMA AB 1 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Common Trip |
Product FAQs
5 answersHow many panel spaces does the QO2401021 require?
This breaker requires three total panel spaces. The 2-pole breaker occupies two spaces, and the factory-installed shunt trip accessory requires one additional space.
What does the 1021 suffix mean on this Square D breaker?
The 1021 suffix indicates that the breaker includes a factory-installed 120/240VAC shunt trip accessory. This allows the breaker to be tripped remotely for emergency shutdowns or automated control.
Which electrical panels are compatible with the QO2401021?
This plug-on breaker is designed for use in Square D QO load centers, as well as NQ and NQOD panelboards. It is not compatible with Homeline or I-Line panels.
How do I wire the shunt trip on the QO2401021?
The shunt trip requires a 120V to 240V AC control voltage. You must land the control circuit wires on the two terminals provided on the shunt trip module to enable remote tripping.
Does this breaker have a visual trip indicator?
Yes, it features the Square D Visi-Trip indicator. When the breaker trips due to an overload, short circuit, or a shunt trip command, a red flag appears in the indicator window for quick identification.
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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