Skip to main content
Expedited shipping available at checkout

Square D LLA36400U44X Molded Case Circuit Breaker

  • 400A
  • 3 Pole
  • I-Line
Square D LLA36400U44X
Molded Case Circuit Breaker
Brand Square D
SKU LLA36400U44X
Select Item Condition
Earn 10784 SuperPoints
  • 400A
  • 3 Pole
  • I-Line

Quantity

Bulk Pricing
Send your parts list for a volume quote.

Square D LLA36400U44X - 400A 3 Pole Molded Case Circuit Breaker

New

$10,784.06 In Stock

Quantity

Description

Designed for maximum facility safety, this 400A electronic trip circuit breaker incorporates advanced ground fault sensing. The PowerPacT L-Frame device is ideal for heavy-duty power distribution. Utilizing the proven I-Line mounting configuration, it installs into standard Square D switchboards. Facility managers can use this model to upgrade legacy LA36400 and LH36400 breakers. The MicroLogic 6.3A trip unit features LSIG functions alongside a built-in ammeter for precise monitoring.

Specifications

Key specifications
Brand Square D
Part Number KC34125G-R
Series LLA
Amperage 400A
Poles 3
Mounting Style I-Line
Voltage 240VAC, 480VAC, 600VAC
Phase 3
AIC Rating 125kA @ 240VAC, 100kA @ 480VAC, 50kA @ 600VAC
Electrical ratings
Amperage Range 160-400A
Fit and installation
Frame Type LLA
Terminal Type Lugs
For Use With I-Line Panelboards, I-Line Switchboards
Wire Gauge (2) 2/0 AWG-500 kcmil (Al/Cu)
Max Wire 500 kcmil
Min Wire 2/0 AWG
Protection and operation
Trip Technology Electronic Trip
Trip Function Code LSIG
Trip Function Long-Time, Short-Time, Instantaneous, Ground Fault
Trip Adjustability Adjustable
Trip Unit Model Ammeter
Standards and features
Available Options Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment, Communication Module
Accessories MicroLogic 6.3A Trip Unit, 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 Current Limiting, HACR Rated, True RMS Sensing, Ground Fault Protection, Phase Loss Protection

Product FAQs

8 answers
What does the U44X suffix indicate on the LLA36400U44X?

The U44X suffix designates a Micrologic 6.3 A electronic trip unit. It provides LSIG (Long-Time, Short-Time, Instantaneous, and Ground-Fault) protection along with integrated ammeter capabilities for current monitoring.

Does the LLA36400U44X require a neutral current transformer for 4-wire systems?

Yes. Because this breaker includes ground-fault protection, installing it in a 3-phase, 4-wire system requires an external neutral current transformer to accurately monitor neutral currents and prevent nuisance tripping.

How much mounting space does this L-Frame breaker require in an I-Line panelboard?

PowerPacT L-Frame circuit breakers require 6 inches of mounting space in an I-Line panelboard or switchboard.

Are the load lugs factory installed on the LLA36400U44X?

Yes, this breaker comes with factory installed mechanical lugs on the load side. They accept two 2/0 AWG to 500 kcmil aluminum or copper conductors per phase. The line side features the I-Line plug-in jaw connections.

Can I add auxiliary contacts or a shunt trip to this breaker?

Yes, the PowerPacT L-Frame series supports a full range of field installable internal accessories, including auxiliary switches, alarm switches, and shunt trips. These are installed under the front accessory cover.

Is the LLA36400U44X rated for 100 percent continuous current?

No, this breaker is standard 80 percent rated. For continuous loads lasting 3 hours or more, the load must not exceed 320 amps, which is 80 percent of its 400A rating.

Can the LLA36400U44X be reverse fed?

No. I-Line circuit breakers feature plug-in jaws on the line side and mechanical lugs on the load side, making them physically incompatible with reverse feed applications.

How do I identify if the LLA36400U44X has tripped?

The breaker features an over-center toggle mechanism. When it trips due to an overcurrent or ground fault, the handle snaps to a center position, providing a clear visual indication that the circuit has opened.

SuperClub

Join free. Get 500 SuperPoints.

Earn points on eligible purchases and redeem them at checkout.

100 SuperPoints = $1 off.

Warranties

60-Day Warranty

Your purchase includes 60 days of SuperBreakers warranty coverage.

Get a Quote

Don’t see what you’re looking for?

We source obsolete and hard-to-find parts every day.

Shipping

Free Shipping Policy

Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.

Read our full shipping policy

Same Day Shipping

We strive to ship out your items the same day the order is placed. In rare circumstances SuperBreakers may reserve up to 5 business days to consolidate orders for complete shipment.

Expedited Shipments

Orders being shipped via Next Day Air, 2 Day Shipping or 3 Day Shipping must be received by 3 PM EST to guarantee same-day shipments. Expedited orders only ship on normal business days. Shipments will NOT be sent out on Saturdays and Sundays.

International Shipping

All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.