Free Shipping Over $99
Square D FA24040AB Molded Case Circuit Breaker
- 40A
- 2 Pole
- I-Line
Square D
FA24040AB
Molded Case Circuit Breaker
Brand
Square D
SKU
FA24040AB
Quantity
Shop with Confidence
Add an extra year of protection in your cart.
Square D FA24040AB - 40A 2 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Square D FA24040AB - 40A 2 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | FA24040AB |
| Series | FA |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480Y/277VAC, 480VAC, 250VDC |
| Phase | 1 |
| AIC Rating | 25kA @ 240VAC, 18kA @ 480Y/277VAC, 18kA @ 480VAC, 10kA @ 250VDC |
| Frame Type | F |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards |
| Wire Gauge | 14-1/0 AWG (Cu/Al) |
| Max Wire | 1/0 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Phase Connection AB |
| Standards | CSA C22.2 No. 5, HACR, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Quantity
Square D FA24040AB - 40A 2 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | FA24040AB-R |
| Series | FA |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480Y/277VAC, 480VAC, 250VDC |
| Phase | 1 |
| AIC Rating | 25kA @ 240VAC, 18kA @ 480Y/277VAC, 18kA @ 480VAC, 10kA @ 250VDC |
| Frame Type | F |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards |
| Wire Gauge | 14-1/0 AWG (Cu/Al) |
| Max Wire | 1/0 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Phase Connection AB |
| Standards | CSA C22.2 No. 5, HACR, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Similar Items
40A 2 Pole Molded Case Circuit Breaker
40A 2 Pole Molded Case Circuit Breaker
40A 2 Pole Molded Case Circuit Breaker
Description
Part of Square D's legacy F-Frame lineup, the FA24040AB is a 2-pole molded case circuit breaker engineered for commercial and industrial applications. It delivers reliable thermal-magnetic protection with long-time and instantaneous (LI) trip functions. This unit installs into Square D I-Line panelboards and switchboards, utilizing a dedicated AB phase connection. Rated for 40A at 480VAC, it provides an 18kAIC interrupting capacity. Note that this model is replaced by the HDA260401.Specifications
| Brand | Square D |
|---|---|
| Part Number | FA24040AB |
| Series | FA |
| Amperage | 40A |
| Poles | 2 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480Y/277VAC, 480VAC, 250VDC |
| Phase | 1 |
| AIC Rating | 25kA @ 240VAC, 18kA @ 480Y/277VAC, 18kA @ 480VAC, 10kA @ 250VDC |
| Frame Type | F |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards |
| Wire Gauge | 14-1/0 AWG (Cu/Al) |
| Max Wire | 1/0 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Fixed Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Phase Connection AB |
| Standards | CSA C22.2 No. 5, HACR, NEMA AB 1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator |
Product FAQs
4 answersWhat does the AB suffix mean in the FA24040AB catalog number?
The AB suffix indicates the phase connection. This 2-pole I-Line circuit breaker is configured to connect specifically to the A and B phases on the panelboard bus.
Is the Square D FA frame still manufactured, or is there a modern replacement?
The FA frame is a legacy series that has been discontinued. For modern upgrades in I-Line panelboards, Square D replaced this series with the PowerPact H-frame circuit breakers.
How does the FA24040AB mount into the panelboard?
It utilizes the Square D I-Line plug-on design. The breaker jaws push directly onto the panelboard bus stack, and the unit is secured to the backpan with a captive mounting screw. This allows for faster installation compared to traditional bolt-on breakers.
Will this legacy F-frame breaker fit in newer I-Line panelboards?
Yes, legacy F-frame I-Line breakers like the FA24040AB share the same bus mounting footprint as modern PowerPact H-frame breakers. They are physically compatible with standard Square D I-Line panelboards and switchboards.
SuperClub
Join free. Get 500 SuperPoints.
Earn points on eligible purchases and redeem them at checkout.
100 SuperPoints = $1 off.
Warranties
Add an extra year of protection
60-Day Warranty
Your purchase includes 60 days of SuperBreakers warranty coverage.
Add a 1-year warranty extension in your cart.
Get a Quote
Don’t see what you’re looking for?
We source obsolete and hard-to-find parts every day.
Shipping
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.
Same Day Shipping
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.
Expedited Shipments
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 5.0 out of 5 based on 70 reviews.
Reviews Summary
Generated by AI from 68 most recent customer reviews
Last updated 8/15/26
Customers say this circuit breaker matches its description, fits perfectly, and works as expected. Many reviews highlight fast shipping and quick delivery times, with several noting orders arrived within days. Users appreciate the product condition, describing refurbished units as appearing new without wear or marks. Common feedback addresses competitive pricing compared to local suppliers and the overall value proposition. Customers report straightforward ordering processes and reliable service, with repeat purchasers noting consistent positive experiences. The breaker installed easily and functioned properly in various applications.
Search
Rating
70 reviews
- CPCasey P.Verified BuyerReviewingSquare D FA34030 - 30A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/14/26Great company
Ordered on a Saturday evening, paid for two day shipping and it arrived on time and in perfect condition. Would 100 percent be using this company going forward, beat out pricing and shipping times for all my local supply houses. Plus the staff were great to deal with.
- AHAnn H.Verified BuyerReviewingSquare D FA36100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/22/26Professional Service
So far, so good! The circuit breaker was installed along with a new compressor for our church AC, and everything is now working well.
The company has been professional, dependable, and reputable throughout the process. I had a question after the installation, and it was answered immediately. I also appreciated that they followed up and asked for feedback to make sure the new part was working properly and that we were satisfied with the service.
It’s refreshing to deal with a company that not only has quality products but also cares about its customers after the job is completed. I would definitely recommend them!
- RErene e.Verified BuyerReviewingSquare D FA34070 - 70A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/14/26breaker
breaker was just as discribed
- BEBallentine E.Verified BuyerReviewingSquare D FA24060AC - 60A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/15/26Great
Accurate and on time.
- EBEdward B.Verified BuyerReviewingSquare D FA32100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/1/26As good as new
The Square D FA32100 circuit breaker (refurbished) was as good as a new breaker, without exception. There was no wear and tear or any marks at all. It was basically new. It is an excellent choice and a great product without having to pay the cost of a new breaker.