Engineered for commercial and industrial applications, this unit-mount miniature breaker provides reliable overcurrent protection alongside remote tripping capabilities. It installs into OEM enclosures, control panels, and DIN rail systems using standard mounting hardware. The factory-installed 120/208/240VAC shunt trip allows for automated circuit interruption, while the reversible box lugs accommodate versatile wiring configurations.
OEM Panels, Control Panels, DIN Rail Systems, Enclosures
Wire Gauge
14-2 AWG
Max Wire
2 AWG
Min Wire
14 AWG
Protection and operation
Trip Technology
Thermal Magnetic
Trip Function Code
LI
Trip Function
Long-Time, Instantaneous
Trip Adjustability
Fixed Thermal, Fixed Magnetic
Standards and features
Available Options
Mounting Feet, Padlock Attachment
Accessories
Shunt Trip (Factory Installed)
Standards
CSA C22.2 No. 5, IEC 60947-2, UL 489, HACR Rated
Approval
CSA, HACR, IEC, UL
Temp Rating
40C
Product FAQs
7 answers
What does the -1021 suffix mean on the QOU250-1021 breaker?
The -1021 suffix indicates that this breaker includes a factory-installed shunt trip accessory. This allows the breaker to be tripped remotely using a 120V, 208V, or 240V AC control signal.
Can I add a shunt trip to a standard QOU250 breaker in the field?
No, shunt trips for Square D QOU breakers must be factory-installed. If your application requires remote tripping capabilities, you must order a breaker with the appropriate suffix, such as this QOU250-1021 model.
How much physical space does the QOU250-1021 require?
Although it is a 2-pole breaker, the factory-installed shunt trip requires an additional pole space. The total width of the unit is 2.25 inches, which is equivalent to three standard 0.75-inch pole spaces.
What size wire do the terminals on this breaker accept?
The slotted box lugs on both the line and load sides accept 14 AWG to 2 AWG aluminum or copper conductors. The separate shunt trip accessory terminals accept up to two 14 AWG to 12 AWG copper wires.
How is the QOU250-1021 mounted?
As a QOU series unit-mount breaker, it is designed for cable-in and cable-out applications. It can be surface-mounted, flush-mounted, or installed on a standard DIN rail using the appropriate Square D mounting hardware.
Is this breaker compatible with standard QO load centers?
No, QOU series breakers are unit-mount and do not plug or bolt onto a panelboard bus. They are designed for OEM panels, control panels, and standalone enclosures rather than standard QO or QOB load centers.
Does this breaker feature a Visi-Trip indicator?
Yes, Square D QOU breakers include the Visi-Trip indicator. When the breaker trips due to an overcurrent event or a remote shunt trip signal, a highly visible red indicator appears to help you quickly identify the open circuit.
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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 106 reviews.
5.0
Rated 5.0 out of 5 stars
Based on 106 reviews
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102
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Reviews Summary
Generated by AI from 99 most recent customer reviews
Last updated 5/14/26
Customers say these circuit breakers function properly and arrive quickly. Many reviews highlight fast shipping, competitive pricing, and reliable product condition upon arrival. Users appreciate the wide selection, including hard-to-find models, and note the breakers work as expected for various applications. Common feedback addresses quick order processing and easy website navigation. Most customers report satisfaction with value and delivery speed, with many indicating they will purchase again.
Square D QOU260 - 60A 2 Pole Miniature Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
9/7/26
Good thing
i recommend this for you
RG
Robert G.
Verified Buyer
Reviewing
Square D QOU340 - 40A 3 Pole Miniature Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
9/3/26
Circuit breakers
I appreciate the fact that you had these in stock. my Square D distributor does not seem to stock these anymore and it takes a couple weeks to get. your pricing is inline with theirs.
TH
Tiffany H.
Verified Buyer
Reviewing
Square D QOU115 - 15A 1 Pole Miniature Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
8/28/26
Will use Super Breakers again
Arrived in a timely manner. Exactly what we needed for a job.
CS
Cary S.
Verified Buyer
Reviewing
Square D QOU250 - 50A 2 Pole Miniature Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
8/12/26
Just what I ordered
Just what I needed for dock pedestal
MH
Mark H.
Verified Buyer
Reviewing
Square D QOU250VH - 50A 2 Pole Miniature Circuit Breaker
I recommend this product
Rated 5 out of 5 stars
8/11/26
Square D QOU250VH - 50A 2 Pole Miniature Circuit Breaker