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Wadsworth A40NI Miniature Circuit Breaker
- 40A
- 1 Pole
- Plug-On
Wadsworth
A40NI
Miniature Circuit Breaker
Brand
Wadsworth
SKU
A40NI
Quantity
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Wadsworth A40NI - 40A 1 Pole Miniature Circuit Breaker
New
Quantity
Quantity
Wadsworth A40NI - 40A 1 Pole Miniature Circuit Breaker
New
Quantity
| Brand | Wadsworth |
|---|---|
| Part Number | A40NI |
| Series | A |
| Amperage | 40A |
| Poles | 1 |
| Mounting Style | Plug-On |
| Voltage | 120VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120VAC |
| Frame Type | A-NI |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | Wadsworth Type A Load Centers |
| Wire Gauge | 14-4 AWG |
| Max Wire | 4 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Standards | UL 489 |
|---|---|
| Approval | UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
Quantity
Wadsworth A40NI - 40A 1 Pole Miniature Circuit Breaker
Re-Certified
Quantity
| Brand | Wadsworth |
|---|---|
| Part Number | A40NI-R |
| Series | A |
| Amperage | 40A |
| Poles | 1 |
| Mounting Style | Plug-On |
| Voltage | 120VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120VAC |
| Frame Type | A-NI |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | Wadsworth Type A Load Centers |
| Wire Gauge | 14-4 AWG |
| Max Wire | 4 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Standards | UL 489 |
|---|---|
| Approval | UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
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Description
Legacy panelboards require precise physical dimensions to maintain safe busbar connections. This single-pole 40A breaker slides into Wadsworth Type A load centers, offering an exact match for aging infrastructure. Delivering standard 10kAIC interrupting capacity at 120VAC, the thermal-magnetic trip mechanism responds accurately to overcurrent events. It features box lug terminals accepting 14-4 AWG wire, making it ideal for residential upgrades.Specifications
| Brand | Wadsworth |
|---|---|
| Part Number | A40NI |
| Series | A |
| Amperage | 40A |
| Poles | 1 |
| Mounting Style | Plug-On |
| Voltage | 120VAC |
| Phase | 1 |
| AIC Rating | 10kA @ 120VAC |
| Frame Type | A-NI |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | Wadsworth Type A Load Centers |
| Wire Gauge | 14-4 AWG |
| Max Wire | 4 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Standards | UL 489 |
|---|---|
| Approval | UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated |
Product FAQs
4 answersWhich load centers are compatible with the A40NI circuit breaker?
This breaker features a proprietary plug-in design exclusively for use in legacy Wadsworth Type A load centers. It will not fit modern panels from brands like Square D, Siemens, or Eaton.
Is there a modern replacement for the Wadsworth A40NI?
Yes. Connecticut Electric manufactures a direct aftermarket replacement under the catalog number UBIA40NI. These replacements are ETL listed to UL 489 standards and fit the same Wadsworth Type A panels.
Are Wadsworth circuit breakers still being manufactured?
No. Wadsworth is an obsolete brand and no longer manufactures new equipment. Electricians must source original legacy stock or use certified aftermarket replacements like the Connecticut Electric UBIA series.
What should be inspected before installing a replacement breaker in a Wadsworth panel?
Because Wadsworth load centers are obsolete, electricians should carefully inspect the panel busbars for signs of pitting, corrosion, or arcing before installing a replacement breaker to ensure a secure connection and prevent overheating.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 5 reviews.
Total 5 star reviews: 5 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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Rating
5 reviews
- PSPaul S.Verified BuyerReviewingWadsworth A15NI - 15A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/14/26Worked fine, glad to have it.
I had no idea how much it could cost.
- DPDavid P.Verified BuyerReviewingSquare D 9065ARO1R Overload RelayI recommend this productRated 5 out of 5 stars11/3/25Loved it!
Fantastic!!!
- KJKevin J.ReviewingWadsworth A260NI - 60A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars1/11/24Great deal
Came on time in great shape
- VJVernice J.ReviewingWadsworth A240NI - 40A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/16/20Order of Breaker
This company did an excellent job with providing a good part and delivery exceeded my expectations.
- HOHugh O.ReviewingGeneral Electric AF43S Panel Board CoverI recommend this productRated 5 out of 5 stars9/24/17Breaker panel
I recently purchased a breaker panel cover. It arrived in a timely manner well packed and unharmed.
The shipping was free so I was sceptical.
All is well.