Free Shipping Over $99
Free Shipping Over $99
Free Shipping Over $99
Free Shipping Over $99
Square D KA36125 Molded Case Circuit Breaker
- 125A
- 3 Pole
- I-Line
Square D
KA36125
Molded Case Circuit Breaker
Brand
Square D
SKU
KA36125
Quantity
Shop with Confidence
Add an extra year of protection in your cart.
Square D KA36125 - 125A 3 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Square D KA36125 - 125A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | KA36125 |
| Series | KA |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 25kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Frame Type | KA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 4 AWG - 350 kcmil (Al/Cu) |
| Max Wire | 350 kcmil |
| Min Wire | 4 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, HACR, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Non-Interchangeable Trip |
Quantity
Square D KA36125 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | KA36125-R |
| Series | KA |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 25kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Frame Type | KA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 4 AWG - 350 kcmil (Al/Cu) |
| Max Wire | 350 kcmil |
| Min Wire | 4 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, HACR, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Non-Interchangeable Trip |
Similar Items
110A 3 Pole Molded Case Circuit Breaker
150A 3 Pole Molded Case Circuit Breaker
100A 3 Pole Molded Case Circuit Breaker
Description
Engineered for commercial environments, the Square D KA36125 is a 3-pole, 125A MCCB. It provides essential protection through a reliable thermal-magnetic trip unit with an adjustable magnetic threshold. This legacy K-Frame breaker features a plug-on connection that mounts into Square D I-Line panelboards. For complete panel upgrades, this model is replaced by the PowerPact HGA36125. Rated for 25kAIC at 480VAC, it includes a Visi-Trip indicator to easily spot tripped circuits.Specifications
| Brand | Square D |
|---|---|
| Part Number | KA36125 |
| Series | KA |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 25kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Frame Type | KA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 4 AWG - 350 kcmil (Al/Cu) |
| Max Wire | 350 kcmil |
| Min Wire | 4 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed Thermal, Adjustable Magnetic |
| Available Options | Shunt Trip, Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Load Side Lugs Included |
| Standards | CSA C22.2 No. 5, HACR, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, Non-Interchangeable Trip |
Product FAQs
7 answersWhat is the modern replacement for the legacy KA36125 circuit breaker?
The KA36125 is a legacy K-frame breaker. For panel upgrades requiring a modern equivalent, Schneider Electric recommends the PowerPact H-frame series, such as the HGA36125, which provides the same 125A, 3-pole I-Line configuration.
Is the KA36125 compatible with standard Square D NQ or NF panelboards?
No. This breaker is specifically designed with an I-Line plug-on connection. It will only mount in Square D I-Line panelboards and switchboards, not standard NQ or NF distribution panels.
How does the adjustable magnetic trip function on this breaker?
The KA36125 features a thermal-magnetic trip unit where the thermal overload protection is fixed, but the magnetic short-circuit trip threshold can be manually adjusted. This allows installers to properly coordinate the instantaneous trip point with other downstream protection devices.
How is the KA36125 breaker installed in the panel?
It utilizes an I-Line plug-on mounting style for the line side, which seats directly onto the panelboard bus. The load side connections are made using mechanical lugs that accept 4 AWG to 350 kcmil aluminum or copper wire.
Can the trip unit be swapped or upgraded in the field?
No, the KA36125 is constructed with a non-interchangeable trip unit. The factory-installed thermal-magnetic trip components cannot be removed or upgraded by the user.
Does the KA36125 feature a visual trip indicator?
Yes, this breaker includes a Visi-Trip indicator. When a fault causes the breaker to trip, the handle rests in a center position and a high-visibility indicator appears, making it easy to visually spot the tripped circuit in an active panelboard.
Is this circuit breaker rated for use in DC systems?
Yes, the KA36125 is rated for both alternating current (AC) and direct current (DC) systems. It carries a DC interrupting rating of 10kA at 250VDC. Always verify DC suitability on the physical nameplate before applying it to battery strings or charger feeder circuits.
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 4.9 out of 5 based on 14 reviews.
Total 5 star reviews: 13 Total 4 star reviews: 1 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Search
Rating
14 reviews
- RFRon F.Verified BuyerReviewingSquare D KA36150 - 150A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/27/26Square D KA36150
As usual, on time and in great condition!
- SJShawn J.Verified BuyerReviewingSquare D KA36225 - 225A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars4/27/26I Line BreKER
Found exactly what I was looking for. They called and set over specs so I could confirm the fit!
- RFRon F.Verified BuyerReviewingSquare D KA36100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars4/9/26Multiple orders
I have purchased multiple breakers (of fairly large size) from SuperBreakers and their pricing has been excellent and the delivery time spot on. I would highly recommend them
- MFMatt F.Verified BuyerReviewingSquare D KA36100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/21/25Order Messed Up - Breaker Great
I have ordered many breakers through SuperBreakers with no issues until this order. I ordered this breaker and it wasn't shipped. I sent a message and was told that a mistake was make in shipping and that they would next day air the breaker to me. 5 days later (weekend in there) the breaker arrived. Not next day air, but shit happens. Sent the breaker still in the box out with my electrician and received a call from him that the breaker that was sent was a KAL36100 not the KA36100. I reached out to SuperBreakers and was told the correct breaker would be next day aired that day and I was emailed a shipping label to send back the incorrect one. This time it arrived the next day and was installed. This error cost my customer a couple days with out power to a dimmer cabinet and about 2 extra hours of labor, but all was okay in the end. Mistakes happen. The help and quick responses to my emails I received from Mike David showed me enough about this company. I look forward to my next order. Thank you for working this situation out in timely manor.
- JHJoel H.Verified BuyerReviewingSquare D KA36200 - 200A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/5/25Worked As Planned
They had what we needed to match existing equipment, they shipped the same day and we put it right into service, no problems from first phone call to delivery and install.