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Eaton / Cutler-Hammer K3125 Molded Case Circuit Breaker
- 125A
- 3 Pole
- Bolt-On
Eaton / Cutler-Hammer
K3125
Molded Case Circuit Breaker
Brand
Eaton / Cutler-Hammer
SKU
K3125
Quantity
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Eaton / Cutler-Hammer K3125 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Sold out
Quantity
Eaton / Cutler-Hammer K3125 - 125A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Eaton / Cutler-Hammer |
|---|---|
| Part Number | K3125 |
| Series | K |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 25kA @ 240VAC, 22kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Eaton Series C Panelboards, Westinghouse Panelboards, Motor Control Centers, Switchboards |
| Wire Gauge | 3 AWG - 350 kcmil (Al/Cu) |
| Max Wire | 350 kcmil |
| Min Wire | 3 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 | Lug Kit (TA300K) |
| Standards | HACR, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit, Reverse Feed |
Quantity
Eaton / Cutler-Hammer K3125 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Eaton / Cutler-Hammer |
|---|---|
| Part Number | K3125-R |
| Series | K |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 25kA @ 240VAC, 22kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Eaton Series C Panelboards, Westinghouse Panelboards, Motor Control Centers, Switchboards |
| Wire Gauge | 3 AWG - 350 kcmil (Al/Cu) |
| Max Wire | 350 kcmil |
| Min Wire | 3 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 | Lug Kit (TA300K) |
| Standards | HACR, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit, Reverse Feed |
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Description
Delivering reliable 125A performance, the Eaton K3125 is a 3-pole molded case circuit breaker designed for commercial networks. It handles up to 600VAC, providing essential overcurrent protection. This K-Frame device mounts securely into Eaton Series C panelboards and switchboards. It offers backward compatibility for vintage Westinghouse enclosures and is replaced by the KD3125. Unlike standard models, it features an adjustable magnetic trip for fine-tuned instantaneous response.Specifications
| Brand | Eaton / Cutler-Hammer |
|---|---|
| Part Number | K3125-R |
| Series | K |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 25kA @ 240VAC, 22kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Eaton Series C Panelboards, Westinghouse Panelboards, Motor Control Centers, Switchboards |
| Wire Gauge | 3 AWG - 350 kcmil (Al/Cu) |
| Max Wire | 350 kcmil |
| Min Wire | 3 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 | Lug Kit (TA300K) |
| Standards | HACR, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Interchangeable Trip Unit, Reverse Feed |
Product FAQs
9 answersWhat types of equipment are compatible with the K3125 breaker?
This K-frame breaker is designed for use in Eaton Series C panelboards, legacy Westinghouse panelboards, motor control centers, and switchboards that accept bolt-on molded case circuit breakers.
Can the trip settings on the K3125 be adjusted?
The thermal trip element is fixed, but the magnetic instantaneous trip function is adjustable to allow coordination with other protective devices in the system.
What wire sizes are accepted by the standard lugs on this breaker?
The standard terminals accept aluminum or copper conductors ranging from 3 AWG up to 350 kcmil.
Can this breaker replace an older Westinghouse K3125?
Yes, Eaton acquired the Westinghouse distribution equipment line. A modern Eaton or Cutler-Hammer K3125 is a direct replacement for a legacy Westinghouse breaker with the exact same catalog number.
Is the K3125 rated for use in DC circuits?
Yes, it carries a direct current rating of up to 250VDC with an interrupting capacity of 10kA, making it suitable for specific DC applications.
Is there a newer replacement model for the K3125?
Yes, the KD3125 is the direct replacement model for the K3125 within the Eaton Series C family.
Is there a high interrupting capacity version of this breaker?
Yes, the HK3125 is the high interrupting capacity version, offering up to 65kA at 480VAC compared to the standard 22kA rating of the K3125.
Can the K3125 be reverse fed?
Yes, this breaker features reverse feed capabilities, allowing it to be wired in either direction without compromising its protective functions.
Is this breaker HACR rated?
Yes, the K3125 is HACR rated, meaning it is approved for use with heating, air conditioning, and refrigeration equipment.
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