Square D KC341251021 Molded Case Circuit Breaker
- 125A
- 3 Pole
- I-Line
Quantity
Square D KC341251021 - 125A 3 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Square D KC341251021 - 125A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Part Number | KC341251021 |
| Series | KC |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 4 AWG - 350 kcmil |
| 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 | Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Lugs (AL250KA), Shunt Trip (120-240VAC) |
| 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 |
Quantity
Square D KC341251021 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Part Number | KC341251021 |
| Series | KC |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 4 AWG - 350 kcmil |
| 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 | Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Lugs (AL250KA), Shunt Trip (120-240VAC) |
| 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 |
Description
Part of the legacy K-Frame series, this 125A molded case circuit breaker provides thermal-magnetic protection for industrial environments. It features long-time and instantaneous trip functions. The device installs into Square D I-Line panelboards and switchboards. For future upgrades, this model is replaced by the JJA36125SA. A factory-installed 120-240VAC shunt trip allows remote tripping. It boasts an extra-high 100kAIC rating at 240V for demanding fault currents.Specifications
| Brand | Square D |
|---|---|
| Part Number | KC341251021 |
| Series | KC |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Square D I-Line Panelboards and Switchboards |
| Wire Gauge | 4 AWG - 350 kcmil |
| 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 | Auxiliary Switch, Alarm Switch, Undervoltage Release |
|---|---|
| Accessories | Lugs (AL250KA), Shunt Trip (120-240VAC) |
| 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 |
Product FAQs
6 answersWhat does the 1021 suffix indicate on the KC341251021 catalog number?
The 1021 suffix indicates that this breaker includes a factory-installed 120/240VAC shunt trip. This accessory allows for remote tripping of the circuit breaker.
What is the modern PowerPact replacement for this legacy K-Frame breaker?
For future upgrades or panel retrofits, this legacy KC breaker is replaced by the Square D PowerPact J-Frame series, specifically catalog number JJA36125SA.
Can I install the KC341251021 in a standard Square D load center?
No. This breaker features an I-Line style plug-in mounting system and is exclusively compatible with Square D I-Line panelboards and switchboards.
How does the thermal-magnetic trip unit operate on this breaker?
This breaker uses an LI (Long-Time, Instantaneous) trip unit. It provides fixed thermal protection for sustained overloads and adjustable magnetic protection, allowing you to fine-tune the instantaneous short-circuit response.
What are the wire size requirements for the terminal lugs on the KC341251021?
The factory-installed lugs are designed to accept wire gauges from 4 AWG up to 350 kcmil.
Is this breaker suitable for DC voltage applications?
Yes, in addition to its AC ratings, this breaker is rated for use in 250VDC systems with an interrupting capacity of 10kA.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 1 review.
- TDTammy D.Verified BuyerReviewingSquare D KC34200 - 200A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/9/26Breakers
great service!! I had bought 3 different breakers & there was one that i had to return. I called as soon as i realized it was wrong.( my fault) I had my return RMA in about 5 minutes of the phone call. Highly recommend!!