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Square D EJB14040 Miniature Circuit Breaker
- 40A
- 1 Pole
- Bolt-On
Square D
EJB14040
Miniature Circuit Breaker
Brand
Square D
SKU
EJB14040
Quantity
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Square D EJB14040 - 40A 1 Pole Miniature Circuit Breaker
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Description
Providing robust overcurrent protection, the Square D EJB14040 is a 1-pole, 40A miniature circuit breaker from the E-Frame family. It features reliable thermal-magnetic trip technology and a Visi-Trip indicator. This unit bolts into Square D NF panelboards. It features standard aluminum lugs that accept 14-2/0 AWG copper or 12-2/0 AWG aluminum wiring. With a maximum voltage of 277VAC, it delivers a 100kAIC interrupting rating at 120V and 65kAIC at 277V. It is HACR and HID rated.Specifications
| Brand | Square D |
|---|---|
| Part Number | EJB14040 |
| Series | EJB |
| Amperage | 40A |
| Poles | 1 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC, 240VAC, 277VAC |
| Phase | 1 |
| AIC Rating | 100kA @ 120VAC, 65kA @ 240VAC, 65kA @ 277VAC |
| Frame Type | EJB |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D NF Panelboards |
| Wire Gauge | 14-2/0 AWG (Cu), 12-2/0 AWG (Al) |
| Max Wire | 2/0 AWG |
| Min Wire | 14 AWG (Cu) / 12 AWG (Al) |
| 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 | Aluminum Lugs Included |
| Standards | CSA C22.2 No. 5, NEMA AB 1, NFPA 70, UL 489 |
| Approval | CSA, cULus, HACR, HID, NOM, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, HID Rated, Visual Trip Indicator |
Product FAQs
10 answersWhat panelboards are compatible with the EJB14040 circuit breaker?
The EJB14040 is designed exclusively for use in Square D NF series panelboards. It features a bolt-on connection that mounts directly to the NF panel bus.
Can the EJB14040 replace an EDB14040 or EGB14040 breaker?
Yes. The EJB14040 shares the same physical E-frame footprint as the EDB14040 and EGB14040, but it offers a higher interrupting rating of 65kA at 277VAC. It can be used as a direct upgrade in NF panelboards where higher fault current protection is required.
Is the EJB14040 suitable for switching fluorescent lighting loads?
Yes, this breaker is UL Listed as SWD (Switching Duty), meaning it is approved for switching 120V or 277V fluorescent lighting loads on a regular basis.
Can this breaker be used with High Intensity Discharge (HID) lighting?
Yes, the EJB14040 is UL Listed as HID rated, making it suitable for switching High Intensity Discharge lighting circuits, which typically have high inrush currents.
Is the EJB14040 HACR rated for HVAC equipment?
Yes, all Square D EDB, EGB, and EJB circuit breakers are UL Listed as HACR type, meaning they are approved for use with heating, air conditioning, and refrigeration equipment.
What is the recommended lug torque for the EJB14040?
The recommended tightening torque for the load lugs is 34.5 lb-in for 14-10 AWG wire, and 49.6 lb-in for 8-2/0 AWG wire.
Does the EJB14040 require a separate mounting kit for installation?
No separate mounting kit is required. The breaker features a built-in bolt-on connector that fastens directly to the bus bar of a Square D NF panelboard.
Does the EJB14040 include ground fault or arc fault protection?
No, the standard EJB14040 provides only thermal-magnetic overload and short-circuit protection. It does not include GFCI or AFCI capabilities. Breakers with equipment ground fault protection will have an EPD suffix in the catalog number.
Can I install the EJB14040 in a Square D NQ or QO panelboard?
No. The EJB14040 is an E-frame breaker built specifically for 277VAC or 480Y/277VAC NF panelboards. It will not fit in NQ or QO panelboards, which require QO or QOB series breakers.
Does the EJB14040 feature a visual trip indicator?
Yes, this breaker includes a visual trip indicator that provides clear confirmation when the breaker has tripped due to an overload or short circuit.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 13 reviews.
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Rating
13 reviews
- JMJessica M.Verified BuyerReviewingSquare D EJB34060 - 60A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/16/26Exactly what we needed
Purchased the Square D EJB34060 60A 3-Pole circuit breaker for a commercial electrical application. The breaker arrived as described, was well packaged, and was the correct Square D part we needed.
Electrical components like this can sometimes be difficult to locate, so it was great to find the exact breaker without having to substitute or modify the existing equipment. Installation went smoothly and the breaker fit and operated as expected.
Very satisfied with the purchase and would order again when we need hard-to-find Square D electrical equipment.
- EOEric O.Verified BuyerReviewingSquare D EJB14040 - 40A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/5/26Breaker Replacement
I needed a replacement breaker fast, and SuperBreakers pulled it off for me without any issues.
- BBBrad B.Verified BuyerReviewingSquare D EJB34125 - 125A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars6/27/26Breaker Order
Thanks! Ordering was easy and the part was delivered quickly and accurately. All I can ask for!
- RRRodolfo R.Verified BuyerReviewingSquare D EJB34015 - 15A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars1/14/26Satisfied Customer
The breaker was received in good condition and it works good. Lead time was not long it all.
Very happy with SuperBreakers Rep. Good customer service.
- RNRandy N.Verified BuyerReviewingSquare D EJB34070 - 70A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars11/14/25Breaker value
saved a lot compared to what the electrician wanted to charge us, at least half the price.