Eaton / Westinghouse NB31000 Molded Case Circuit Breaker
- 1000A
- 3 Pole
- Bolt-On
Quantity
Eaton / Westinghouse NB31000 - 1000A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Part of the classic AB frame family, this 1000-amp thermal-magnetic breaker provides reliable long-time and instantaneous trip functions for industrial facilities. Designed as an exact fit for older Westinghouse PRL4 panelboards and switchboards, it eliminates the need for retrofitting kits. It serves as a drop-in substitute for HNB31000 or ND31000 units.Specifications
| Brand | Eaton / Westinghouse |
|---|---|
| Part Number | NB31000-R |
| Series | NB |
| Amperage | 1000A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 42kA @ 240VAC, 30kA @ 480VAC, 22kA @ 600VAC, 20kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Westinghouse PRL4 Panelboards, Switchboards |
| Wire Gauge | (4) 4/0 AWG - 500 kcmil |
| Max Wire | 500 kcmil |
| Min Wire | 4/0 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 | NEMA AB-1, UL 489 |
| Approval | UL |
| Temp Rating | 40C |
| Construction Features | Interchangeable Trip Unit |
Product FAQs
6 answersWhat panelboards are compatible with the Eaton / Westinghouse NB31000?
This breaker is designed as an exact fit for older Westinghouse PRL4 panelboards and switchboards. It bolts directly to the busbar, eliminating the need for custom retrofitting kits.
Can the NB31000 replace an HNB31000 or ND31000 circuit breaker?
Yes, the NB31000 serves as a drop-in physical substitute for HNB31000 and ND31000 units. Because the HNB31000 has a higher interrupting capacity, you must verify that the 30kA at 480VAC rating of the NB31000 meets your system fault current requirements before installation.
What wire sizes are supported by the lugs on the NB31000?
The included load side lugs accept up to four conductors per phase, accommodating wire sizes from 4/0 AWG to 500 kcmil.
What protection is provided by the LI trip function on this breaker?
The LI code indicates Long-Time and Instantaneous protection. The thermal-magnetic trip unit features a fixed thermal element to protect against overloads and an adjustable magnetic element to clear short circuits.
Is the trip unit on the NB31000 interchangeable?
Yes, this breaker features an interchangeable trip unit design. This allows the thermal-magnetic trip mechanism to be replaced or serviced without removing the entire breaker frame from the panel.
What routine safety inspections are recommended for this 1000A breaker?
Industry best practices for 1000A circuit breakers include a visual inspection of the lugs, contacts, and housing every two years. An operational test of the trip unit should be conducted every five years, as well as immediately following any fault event.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 18 reviews.
- MMMike M.Verified BuyerReviewingFederal Pacific NB100 - 100A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars7/2/26100amp federal pacific breaker
So far the breaker works as expected
Just good to know some of these old federal are still available.
Thank you
- SGscott g.Verified BuyerReviewingFederal Pacific NB111020 - 20A 1 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/26/26Hard to find breakers
Had a project at a school built in the 1960’s and thought we were up a creek when confronted with ancient FPE commercial panels. Luckily we found what we needed with Suoerbreakers.
- BFBarry F.Verified BuyerReviewingFederal Pacific NB100 - 100A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars6/13/26Hard to find circuit breaker
Item was as described.
- WWWilliam W.Verified BuyerReviewingFederal Pacific NB100 - 100A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars3/9/26Exactly what I needed.
Awesome! Packaging and delivery were good. Bolted in and worked perfectly!!)
- GHGary H.Verified BuyerReviewingFederal Pacific NB125 - 125A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars3/3/26Federal Pacific NB125 2 Pole Circuit Breaker
Federal Pacific NB125 2 Pole Circuit Breaker
Great product and excellent price and warranty.