Square D RJF36080U31AJK Molded Case Circuit Breaker
- 800A
- 3 Pole
- Unit Mount
Quantity
Square D RJF36080U31AJK - 800A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Belonging to the Square D PowerPacT R-Frame family, the RJF36080U31AJK is an 800A electronic trip molded case circuit breaker engineered for commercial and industrial distribution. This 3-pole, 600VAC unit-mount breaker installs seamlessly into QED switchboards, Power-Style switchboards, and Model 6 motor control centers. Equipped with a Micrologic 3.0 trip unit, it provides adjustable long-time and instantaneous (LI) protection. It features an 80% rating and a 65kAIC capacity at 480V.Specifications
| Brand | Square D |
|---|---|
| Part Number | RJF36080U31AJK-R |
| Series | RJF |
| Amperage | 800A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 480VAC, 600VAC |
| Phase | 3 |
| AIC Rating | 100kA @ 240VAC, 65kA @ 480VAC, 25kA @ 600VAC |
| Amperage Range | 320-800A |
|---|
| Terminal Type | Busbar Connection |
|---|---|
| For Use With | QED Switchboards, Model 6 Motor Control Centers, Power-Style Switchboards |
| Trip Technology | Electronic Trip |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Adjustable |
| Trip Unit Model | MicroLogic 3.0 |
| Available Options | Shunt Trip, Auxiliary Switch, Undervoltage Release, Alarm Switch, Padlock Attachment, Motor Operator, Rotary Handle, Lug Kits |
|---|---|
| Accessories | Lugs Not Included, Kirk Key Interlock Provision (Factory Installed) |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CE, CSA, IEC, NOM, UL |
| Temp Rating | 40C |
| Construction Features | 80% Rated, HACR Rated |
Product FAQs
9 answersWhich switchboards and motor control centers are compatible with the RJF36080U31AJK circuit breaker?
This R-Frame unit-mount breaker is designed for installation in Square D QED Switchboards, Power-Style Switchboards, and Model 6 Motor Control Centers.
What protection functions are included with the U31A electronic trip unit?
The U31A designation indicates an electronic trip unit equipped with adjustable Long-Time (L) and Instantaneous (I) protection functions. This allows for precise overload and short-circuit coordination in commercial and industrial distribution systems.
How is the RJF36080U31AJK installed into a panel or switchboard?
This is a unit-mount circuit breaker, meaning it is designed for direct busbar connection rather than plugging into an I-Line distribution panel. It bolts directly to the bus in compatible switchboards and enclosures.
Can I use this R-Frame breaker to replace an older M-Frame or P-Frame Square D breaker?
No, PowerPacT R-Frame breakers have different physical dimensions, mounting footprints, and bus connections than legacy M-Frame or P-Frame breakers. You must verify that your switchboard or enclosure is specifically designed to accept an R-Frame unit-mount breaker.
Does the RJF36080U31AJK come with mechanical lugs for wire termination?
No, this unit-mount breaker is designed for direct busbar connection and does not include lugs. If you need to terminate cables, you must purchase the appropriate mechanical or compression lug kits separately based on your conductor size and material.
Is the RJF36080U31AJK rated for 100 percent continuous operation?
Standard PowerPacT R-Frame breakers like the RJF36080U31AJK are 80 percent rated. Continuous loads should not exceed 80 percent of the 800A frame rating (640A) in accordance with standard National Electrical Code (NEC) sizing practices.
Can the RJF36080U31AJK be used in systems requiring a 65kA interrupting capacity at 480V?
Yes, this J-interrupting tier R-Frame breaker provides a 65kA interrupting capacity at 480VAC. It is also rated for up to 100kA at 240VAC and 25kA at 600VAC, making it suitable for high-fault commercial and industrial applications.
Does the RJF36080U31AJK include ground-fault protection?
No, the U31A trip unit on this breaker provides Long-Time and Instantaneous (LI) protection only. If your application requires ground-fault protection, you will need a breaker with a different trip unit configuration.
Can I adjust the trip settings on the RJF36080U31AJK?
Yes, the Micrologic electronic trip unit features adjustable dials for both the Long-Time and Instantaneous pickup settings. This allows you to fine-tune the breaker's protection curve to match your specific load and coordination requirements.
SuperClub
Join free. Get 500 SuperPoints.
Earn points on eligible purchases and redeem them at checkout.
100 SuperPoints = $1 off.
Warranties
Add an extra year of protection
60-Day Warranty
Your purchase includes 60 days of SuperBreakers warranty coverage.
Add a 1-year warranty extension in your cart.
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.
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.