Square D LLL36400U31X Molded Case Circuit Breaker
- 400A
- 3 Pole
- Unit Mount
Quantity
Square D LLL36400U31X - 400A 3 Pole Molded Case Circuit Breaker
New
Quantity
Description
Built for commercial and industrial power distribution, the Square D LLL36400U31X is a 3-pole, 400A molded case circuit breaker. As part of the PowerPact L-Frame series, it utilizes a MicroLogic 3.3 electronic trip unit to deliver precise long-time and instantaneous (LI) protection. This unit-mount MCCB integrates seamlessly into Square D switchboards, motor control centers, and enclosures. Rated at 100kAIC at 480V, it features true RMS sensing and current-limiting performance.Specifications
| Brand | Square D |
|---|---|
| Part Number | LLL36400U31X |
| Series | LLL |
| Amperage | 400A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC, 250VDC |
| Phase | 3 |
| AIC Rating | 125kA @ 240VAC, 100kA @ 480VAC, 50kA @ 600VAC, 20kA @ 250VDC |
| Amperage Range | 125-400A |
|---|
| Frame Type | LLL |
|---|---|
| Terminal Type | Lugs |
| For Use With | Square D Switchboards, Motor Control Centers, Industrial Control Panels, Enclosures |
| 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, Motor Operator, Rotary Handle |
|---|---|
| Accessories | Lugs |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CCC, CE, CSA, IEC, NOM, UL |
| Temp Rating | -25C to 70C |
| Construction Features | HACR Rated, Current Limiting, True RMS Sensing, Visual Trip Indicator, 80% Rated, Mercury Free, RoHS Compliant, PVC Free |
Product FAQs
7 answersWhat is the recommended tightening torque for the lugs on the LLL36400U31X?
The factory-installed AL600LS52K3 lugs require a tightening torque of 442.5 lb-in (50 N.m) for the accepted (2) 2/0 AWG to 500 kcmil aluminum or copper conductors.
Which electronic trip unit is included with this breaker?
The LLL36400U31X comes equipped with a factory-sealed MicroLogic 3.3 standard electronic trip unit, which provides adjustable long-time and instantaneous (LI) protection.
What does the U31X suffix indicate in the LLL36400U31X catalog number?
The U31X suffix designates the specific trip unit installed in the breaker. It indicates that the breaker is equipped with a MicroLogic 3.3 electronic trip unit featuring Long-Time and Instantaneous (LI) protection functions.
Can the LLL36400U31X be reverse fed?
Yes, PowerPacT L-frame circuit breakers equipped with factory-sealed electronic trip units are suitable for reverse connection.
Can this 3-pole breaker be used in a 2-pole application?
Yes, this 3-pole PowerPacT L-frame breaker can be safely applied in 2-pole applications when wired according to the manufacturer instructions.
What does the second L in the LLL prefix signify?
The second L in the LLL prefix indicates the interrupting capacity tier of the PowerPacT L-frame series. It signifies a high interrupting rating of 125kA at 240VAC, 100kA at 480VAC, and 50kA at 600VAC.
Does this breaker plug into an I-Line panelboard?
No, the LLL36400U31X is a unit-mount breaker designed for individual mounting on a backplate or in an enclosure. It is not compatible with I-Line panelboards, which require an I-Line specific catalog number like LLA36400U31X.
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