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Square D KCL34125 Molded Case Circuit Breaker
- 125A
- 3 Pole
- Unit Mount
Square D
KCL34125
Molded Case Circuit Breaker
Brand
Square D
SKU
KCL34125
Quantity
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Square D KCL34125 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
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Square D KCL34125 - 125A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | KCL34125 |
| Series | KCL |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480Y/277VAC, 480VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480Y/277VAC, 65kA @ 480VAC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D Enclosures, Switchboards, Panelboards |
| 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, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Lugs (AL250KA) |
| Standards | CSA C22.2 No. 5, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Extra High Interrupting Capacity, Trip-Free Mechanism, Quick-Make/Quick-Break |
Quantity
Square D KCL34125 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | KCL34125-R |
| Series | KCL |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480Y/277VAC, 480VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480Y/277VAC, 65kA @ 480VAC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D Enclosures, Switchboards, Panelboards |
| 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, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Lugs (AL250KA) |
| Standards | CSA C22.2 No. 5, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Extra High Interrupting Capacity, Trip-Free Mechanism, Quick-Make/Quick-Break |
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Description
Engineered for commercial and industrial applications, the Square D KCL34125 is a 3-pole, 125A molded case circuit breaker. It features a thermal-magnetic trip unit with fixed thermal and adjustable magnetic settings (LI protection) to handle overloads and short circuits. Designed as a unit mount breaker, it installs into compatible Square D enclosures, switchboards, and panelboards. This legacy K-Frame model is rated for 65 kAIC at 480VAC and is replaced by the PowerPacT H-Frame series.Specifications
| Brand | Square D |
|---|---|
| Part Number | KCL34125-R |
| Series | KCL |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480Y/277VAC, 480VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480Y/277VAC, 65kA @ 480VAC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D Enclosures, Switchboards, Panelboards |
| 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, Undervoltage Release, Alarm Switch |
|---|---|
| Accessories | Lugs (AL250KA) |
| Standards | CSA C22.2 No. 5, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Extra High Interrupting Capacity, Trip-Free Mechanism, Quick-Make/Quick-Break |
Product FAQs
6 answersIs the Square D KCL34125 still an active product line?
The K-Frame series is a legacy product line that has been replaced by the modern Square D PowerPacT H-Frame series. Upgrading to a newer PowerPacT breaker requires specific retrofit hardware or mounting modifications to fit into older K-Frame spaces.
How does the KCL34125 differ from KAL34125 or KHL34125 breakers?
The KCL prefix indicates an extra-high interrupting capacity. While the KAL series is the standard interrupting tier and KHL is high interrupting, the KCL34125 offers upgraded fault protection with ratings up to 65kA at 480VAC and 100kA at 240VAC.
What type of trip unit is installed in the KCL34125?
This breaker uses a thermal magnetic trip unit with an LI (Long-Time, Instantaneous) function code. The thermal element provides fixed overload protection, while the magnetic instantaneous trip is adjustable via a front dial to fine-tune the short-circuit response.
Is this circuit breaker compatible with I-Line panelboards?
No. The KCL34125 is a unit mount feed-thru breaker designed for standard enclosures and switchboards requiring lug connections. It does not have the plug-on jaw connections required for Square D I-Line panelboards, which typically use the KIL prefix.
Can I use both aluminum and copper conductors with this breaker?
Yes, the standard factory lugs on the KCL34125 are dual-rated for both aluminum and copper wire, accepting conductor sizes from 4 AWG up to 350 kcmil.
Does the KCL34125 have an HACR rating?
Yes, this K-Frame breaker is HACR rated, meaning it has been tested and approved for safe use with heating, air conditioning, and refrigeration equipment motor loads.
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Reviews
Review summary
Customers rate this product 4.8 out of 5 based on 5 reviews.
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Rating
5 reviews
- BWBrian W.Verified BuyerReviewingSquare D KCL34125 - 125A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/27/26Great!
Quick delivery
- BWBrian W.Verified BuyerReviewingSquare D KCL34200 - 200A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/27/26Great
Quick delivery
- BWBrian W.Verified BuyerReviewingSquare D KCL34225 - 225A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/27/26Works perfect
Quick delivery as well
- BWBrian W.Verified BuyerReviewingSquare D KCL34250 - 250A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/24/26Great Service!
Great condition, quick shipping
- JFJ F.Verified BuyerReviewingSquare D KCL34150 - 150A 3 Pole Molded Case Circuit BreakerI recommend this productRated 4 out of 5 stars5/8/26Breakers are right
I thought I was getting a tshirt too. But, alas, no