Eaton / Cutler-Hammer LA3400PR Molded Case Circuit Breaker
- 400A
- 3 Pole
- Bolt-On
Quantity
Eaton / Cutler-Hammer LA3400PR - 400A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Built for heavy-duty commercial applications, this 400A, 3-pole current-limiting MCCB utilizes a Tri-Pac fused design. It provides reliable thermal-magnetic protection with an adjustable magnetic trip. Designed for bolt-on installation, this breaker fits into legacy Westinghouse and Eaton switchboards and motor control centers. When upgrading, the LCL3400 serves as the modern replacement. With a 200 kAIC rating at 600VAC, it effectively restricts let-through current during severe faults.Specifications
| Brand | Eaton / Cutler-Hammer |
|---|---|
| Part Number | LA3400PR-R |
| Series | LA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 200kA @ 240VAC, 200kA @ 480VAC, 200kA @ 600VAC, 100kA @ 250VDC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Eaton / Westinghouse Panelboards, Switchboards, Motor Control Centers |
| Wire Gauge | (1) 4 AWG-600 kcmil (Al/Cu) or (2) 3/0 AWG-250 kcmil (Al/Cu) |
| Max Wire | 600 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 | Line and Load Lugs Included, Current Limiters |
| Standards | NEMA AB-1, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Current Limiting, Fused, Interchangeable Trip Unit, Tri-Pac |
| Special Features | Current Limiting (Integrally Fused) |
Product FAQs
8 answersWhat equipment is compatible with the LA3400PR circuit breaker?
This bolt-on L-frame breaker is designed for installation in legacy Eaton, Cutler-Hammer, and Westinghouse panelboards, switchboards, and motor control centers.
Is the Eaton LA3400PR interchangeable with older Westinghouse versions?
Yes. Following Eaton's acquisition of the Westinghouse distribution equipment business, the LA3400PR breakers branded under Eaton, Cutler-Hammer, and Westinghouse are physically and electrically interchangeable.
What does the "PR" suffix indicate on the LA3400PR?
The "PR" designates this as a Tri-Pac integrally fused, current-limiting circuit breaker. It utilizes internal fuses to achieve a high interrupting capacity of 200kA at 600VAC and restricts let-through current during severe faults.
What wire sizes do the standard lugs on the LA3400PR accept?
The standard pressure line and load lugs accept either a single 4 AWG to 600 kcmil conductor or two 3/0 AWG to 250 kcmil conductors per phase. The terminals are rated for both aluminum and copper wire.
How is the trip unit configured on the LA3400PR?
This breaker features a thermal-magnetic trip unit with a fixed thermal element for overload protection and an adjustable magnetic element for short-circuit protection. The magnetic trip can be adjusted between 2000A and 4000A.
How does the Tri-Pac current-limiting design protect downstream equipment?
The breaker incorporates internal fuses that react extremely fast during high-level short circuits. This restricts the peak let-through current and energy, protecting downstream electrical components from severe thermal and mechanical stress.
What happens if the internal fuses blow on the LA3400PR?
The Tri-Pac fuse pack is mechanically interlocked with the breaker's tripping mechanism. If the internal fuses blow during a fault, or if the fuse pack is not securely bolted down, the breaker handle will not reset or operate until the fuses are properly replaced.
What is the modern replacement for the obsolete LA3400PR circuit breaker?
When upgrading from the legacy LA-frame LA3400PR, the Eaton Series C LCL3400 serves as the modern current-limiting replacement for use in compatible panelboards and switchboards.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 13 reviews.
- RGRobert G.Verified BuyerReviewingSquare D LA36400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/16/26LA36400
Perfectly boxed and arrived on time. Thanks for the shirt and stickers as well.
- CECraig E.Verified BuyerReviewingEaton / Cutler-Hammer LA3600 - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars10/13/25Westinghouse breaker
Excellent customer service and quick shipping
- CLClifton L.Verified BuyerReviewingSquare D LA36400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/30/25estimator
Good
- BCBenjamin C.Verified BuyerReviewingEaton / Cutler-Hammer LA3225 - 225A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/4/25Refurbished Breaker
Breaker seems to be working great, no complaints from Client
- JMJerry M.ReviewingEaton / Cutler-Hammer LA3400 - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/14/23Where is my breaker?
Where is my breaker?