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Eaton / Westinghouse MA3125 Molded Case Circuit Breaker
- 125A
- 3 Pole
- Bolt-On
Eaton / Westinghouse
MA3125
Molded Case Circuit Breaker
Brand
Eaton / Westinghouse
SKU
MA3125
Quantity
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Eaton / Westinghouse MA3125 - 125A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
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Description
A drop-in replacement for legacy Westinghouse systems, the Eaton MA3125 is a 125A molded case circuit breaker built for industrial power distribution. This bolt-on MCCB mounts into vintage PRL4 panelboards and motor control centers. It provides an exact-fit solution, avoiding the adapter kits required by the newer JDB3125 model. Rated 30 kAIC at 480VAC, it features an interchangeable trip unit with adjustable magnetic settings.Specifications
| Brand | Eaton / Westinghouse |
|---|---|
| Part Number | MA3125-R |
| Series | MA |
| Amperage | 125A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 10kA @ 250VDC |
| Frame Type | MA |
|---|---|
| Terminal Type | Lugs |
| For Use With | Westinghouse PRL4 Panelboards, Switchboards, Motor Control Centers |
| Wire Gauge | (1) 14 AWG - 3/0 AWG (Al/Cu) |
| Max Wire | 3/0 AWG |
| Min Wire | 14 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 |
| Standards | CSA C22.2 No. 5, NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Interchangeable Trip Unit |
Product FAQs
5 answersWhich panelboards and distribution systems accept the MA3125 breaker?
This bolt-on molded case circuit breaker is a direct fit for legacy Westinghouse and Eaton Cutler-Hammer PRL4 panelboards, as well as compatible vintage switchboards and motor control centers.
Why choose the MA3125 over the newer JDB3125 replacement?
The MA3125 provides an exact drop-in fit for older Westinghouse systems. Upgrading to the newer JDB3125 requires purchasing and installing a separate adapter kit to make the different frame size fit into your existing PRL4 panelboard.
Are the lugs included with the MA3125, and what wire types do they support?
Yes, the breaker comes with factory lugs installed. They are rated for both aluminum and copper (Al/Cu) conductors, accepting a single wire per phase ranging from 14 AWG up to 3/0 AWG.
How does the trip adjustability work on the MA3125?
The breaker is equipped with an interchangeable thermal-magnetic trip unit. The thermal element for long-time overload protection is fixed at 125 amps, while the magnetic element for instantaneous short-circuit protection is adjustable, allowing you to fine-tune the trip threshold for your specific application.
Does the MA3125 support field-installable accessories?
Yes, the MA frame supports various internal accessories. Options such as shunt trips, auxiliary switches, undervoltage releases, and alarm switches can be added for remote tripping and status monitoring.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 1 review.
Total 5 star reviews: 1 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
1 review
- DHDave H.ReviewingSquare D MA36600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/6/25Never had a problem
We like the service and the prices. The re-certified are great for projects that we have in house.