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Square D LJA36400U31X Molded Case Circuit Breaker
- 400A
- 3 Pole
- I-Line
Square D
LJA36400U31X
Molded Case Circuit Breaker
Brand
Square D
SKU
LJA36400U31X
Quantity
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Square D LJA36400U31X - 400A 3 Pole Molded Case Circuit Breaker
New
Quantity
Quantity
Square D LJA36400U31X - 400A 3 Pole Molded Case Circuit Breaker
New
Quantity
| Brand | Square D |
|---|---|
| Series | LJA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 25kA @ 600VAC |
| Amperage Range | 160-400A |
|---|
| Frame Type | L-Frame |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards, Square D I-Line Switchboards |
| Wire Gauge | (2) 2/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 2/0 AWG |
| Trip Technology | Electronic Trip |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Adjustable |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment, Communication Module, Motor Operator |
|---|---|
| Accessories | Load Side Lugs (AL600LF52K3) |
| Standards | CSA C22.2 No 5, IEC 60947-2, NEMA AB1, NOM-003-SCFI-2000, UL 489 |
| Approval | CCC, CE, CSA, IEC, NEMA, NOM, UKCA, UL |
| Temp Rating | -25C to 70C |
| Construction Features | HACR Rated, Current Limiting, True RMS Sensing, Mercury Free, PVC Free, 80% Rated, Double-Break Rotary Contact Structure, Trip-Free Mechanism |
Quantity
Square D LJA36400U31X - 400A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
| Brand | Square D |
|---|---|
| Series | LJA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 25kA @ 600VAC |
| Amperage Range | 160-400A |
|---|
| Frame Type | L-Frame |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards, Square D I-Line Switchboards |
| Wire Gauge | (2) 2/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 2/0 AWG |
| Trip Technology | Electronic Trip |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Adjustable |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment, Communication Module, Motor Operator |
|---|---|
| Accessories | Load Side Lugs (AL600LF52K3) |
| Standards | CSA C22.2 No 5, IEC 60947-2, NEMA AB1, NOM-003-SCFI-2000, UL 489 |
| Approval | CCC, CE, CSA, IEC, NEMA, NOM, UKCA, UL |
| Temp Rating | -25C to 70C |
| Construction Features | HACR Rated, Current Limiting, True RMS Sensing, Mercury Free, PVC Free, 80% Rated, Double-Break Rotary Contact Structure, Trip-Free Mechanism |
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Description
Providing robust overcurrent protection, the Square D LJA36400U31X is a 3-pole, 400A MCCB. It belongs to the PowerPacT L-Frame series, offering reliable 80% rated performance for commercial networks. This unit mounts into Square D I-Line panelboards and switchboards, featuring a plug-on I-Line connection and load side lugs. Equipped with a MicroLogic 3.3 electronic trip unit, it provides adjustable LI trip functions. Rated 65 kAIC at 480VAC, it ensures accurate fault protection.Specifications
| Brand | Square D |
|---|---|
| Series | LJA |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | I-Line |
| Voltage | 240VAC, 480VAC, 600VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 25kA @ 600VAC |
| Amperage Range | 160-400A |
|---|
| Frame Type | L-Frame |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D I-Line Panelboards, Square D I-Line Switchboards |
| Wire Gauge | (2) 2/0 AWG - 500 kcmil (Al/Cu) |
| Max Wire | 500 kcmil |
| Min Wire | 2/0 AWG |
| Trip Technology | Electronic Trip |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Adjustable |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment, Communication Module, Motor Operator |
|---|---|
| Accessories | Load Side Lugs (AL600LF52K3) |
| Standards | CSA C22.2 No 5, IEC 60947-2, NEMA AB1, NOM-003-SCFI-2000, UL 489 |
| Approval | CCC, CE, CSA, IEC, NEMA, NOM, UKCA, UL |
| Temp Rating | -25C to 70C |
| Construction Features | HACR Rated, Current Limiting, True RMS Sensing, Mercury Free, PVC Free, 80% Rated, Double-Break Rotary Contact Structure, Trip-Free Mechanism |
Product FAQs
9 answersWhat does the U31X signify in the LJA36400U31X catalog number?
It indicates that the breaker is equipped with a MicroLogic 3.3 electronic trip unit. This unit provides standard, adjustable Long-Time and Instantaneous (LI) protection functions.
What is the adjustment range for the Long-Time pickup on this 400A circuit breaker?
The MicroLogic 3.3 trip unit features a Long-Time pickup adjustment range from 0.25 to 1.0 times the nominal current. This allows you to dial in the continuous overload protection anywhere from 100A to 400A.
Which enclosures and panelboards accept the LJA36400U31X?
This PowerPacT L-Frame breaker with I-Line connections is designed exclusively for use in Square D I-Line panelboards and I-Line switchboards. It will not mount in standard unit-mount enclosures or QO load centers.
How does the line side of this breaker install into the panelboard?
The breaker snaps directly onto the I-Line bus stack using its plug-on line-side jaws. A mounting foot on the back of the breaker secures it to the panel mounting pan, requiring no additional line-side cables or hardware.
What are the torque specifications for the load lugs on the LJA36400U31X?
The factory AL600LS52K3 mechanical load lugs require a wire binding screw tightening torque of 442 lb-in (50 N-m) for all approved 2/0 AWG to 500 kcmil conductors.
Does the LJA36400U31X feature a push-to-trip mechanism?
Yes. All PowerPacT L-Frame circuit breakers are equipped with an integral push-to-trip button on the front cover. This allows you to manually trip the breaker mechanism to verify mechanical operation before or after installation.
What does the A in the LJA prefix of the catalog number indicate?
The A designates the breaker as having an I-Line connection type. The L stands for the L-Frame family, and the J represents the specific short-circuit interrupting rating tier.
Is the LJA36400U31X rated for 100 percent continuous current?
No, this circuit breaker is standard-rated for 80 percent continuous current. For a 100 percent rated version, you would need a different catalog number suffix.
Does this breaker include lugs on both the line and load sides?
No. Because it is an I-Line breaker, it features a plug-on connection for the line side to attach directly to the panel bus. Mechanical lugs are only present on the load side for outgoing cables.
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Reviews
Review summary
Customers rate this product 4.8 out of 5 based on 4 reviews.
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Rating
4 reviews
- BWBrian W.Verified BuyerReviewingSquare D LJA36400U31X - 400A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars8/27/26Great!
Quick delivery
- JBJeffrey B.Verified BuyerReviewingSquare D LJA36600U31X - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars7/20/26Purchased breaker - Great experience
We recently needed to purchase a specialty breaker for a large commercial project. Zach, our account manager sprung into action and really made this a white glove experience. From communication to speed I was impressed the entire process. Will definitely be using super breakers for our future breaker needs. Would 1500% recommend!
- EVErik V.Verified BuyerReviewingSchneider Electric LJA36600U44X - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars6/11/26Purchase was easy.
The part was as described. Packing was excellent.
Thank you for the quick ship!
- KPKevin P.ReviewingSquare D LJA36600U31X - 600A 3 Pole Molded Case Circuit BreakerI recommend this productRated 4 out of 5 stars11/1/21Easy to order
fast shipping good condition