Part of the PowerPacT P-frame series, the Square D PJA36100U43A is a 3-pole, 1000A electronic trip MCCB designed for robust industrial power distribution. It delivers precise coordination for complex electrical systems. Featuring an I-Line plug-on connection, this breaker mounts seamlessly into Square D I-Line panelboards and switchboards. The standardized design ensures straightforward integration into compatible enclosures. It is equipped with a Micrologic 5.
Square D I-Line Panelboards, Square D I-Line Switchboards
Wire Gauge
(4) 3/0 AWG-500 kcmil (Al/Cu)
Max Wire
500 kcmil
Min Wire
3/0 AWG
Protection and operation
Trip Technology
Electronic Trip
Trip Function Code
LSI
Trip Function
Long-Time, Short-Time, Instantaneous
Trip Adjustability
Adjustable
Trip Unit Model
MicroLogic 5.0A
Standards and features
Available Options
Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment, Motor Operator, Communication Module
Accessories
Lugs (Load Side)
Standards
CSA C22.2 No. 5, HACR, IEC 60947-2, NEMA AB 1, NOM-003-SCFI-2000, RoHS, UL 489
Approval
CE, CSA, IEC, NOM, UL
Temp Rating
-25C to 70C
Construction Features
HACR Rated, 80% Rated, True RMS Sensing
Product FAQs
7 answers
What type of enclosures are compatible with the PJA36100U43A?
This breaker is specifically designed for installation in Square D I-Line panelboards and switchboards. It uses an I-Line style plug-in connection on the line side for direct bus mounting.
What protection functions does the Micrologic trip unit on the PJA36100U43A provide?
The breaker features a Micrologic 5.0A (Ammeter) electronic trip unit that delivers adjustable Long-Time, Short-Time, and Instantaneous (LSI) trip functions for precise system coordination.
What are the conductor requirements for the load-side lugs on this 1000A breaker?
The factory-installed mechanical lugs accommodate four 3/0 AWG to 500 kcmil conductors per phase. They are rated for both aluminum and copper (Al/Cu) wire.
Can the PJA36100U43A be used in 480V systems with high fault current?
Yes, it is rated to safely interrupt up to 65kA of fault current at 480VAC, making it suitable for heavy commercial and industrial distribution systems. It is also rated for 100kA at 240VAC and 25kA at 600VAC.
How is the line-side connection made on the PJA36100U43A?
The breaker utilizes Square D's I-Line plug-on mounting system. The line-side jaws clamp directly onto the panelboard bus, eliminating the need for line-side cabling and speeding up installation.
Does the PJA36100U43A include ground-fault protection?
No, the U43A designation indicates a Micrologic 5.0A trip unit with LSI functions only. It does not include integral ground-fault protection. For LSIG protection, a different trip unit such as the Micrologic 6.0A is required.
Is the PJA36100U43A rated for 100% continuous current?
No, this model carries a standard 80% continuous current rating. Applications requiring a 100% continuous rating will need a different catalog number.
SuperClub
Join free. Get 500 SuperPoints.
Earn points on eligible purchases and redeem them at checkout.
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.
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.
Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 2 reviews.
Square D PJA36120U44A - 1200A 3 Pole Molded Case Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
8/21/25
Help with flood conditions
The whole process with Technitrol was Awesome. Jim the owner was extremely helpful he caught some problems with one of the breakers that I didn't notice very helpful. James and Collin were great also. The whole company really step up helping me determine what path I should take to replace/refurbish breakers that went through a flood. I never experienced a flood like this they were an awesome resource and help to me and my employer the City of Wauwatosa
RN
Ross N.
Reviewing
Square D PJA36080CU31A - 800A 3 Pole Molded Case Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
4/12/22
Stock!
Superbreakers has gotten my company out of a few binds recently. When stock is unavailable at my local supplier I've been turning to Superbreakers to save the day. Great customer service and timely shipments.