Free Shipping Over $99
Free Shipping Over $99
Free Shipping Over $99
Free Shipping Over $99
Square D QOU3201021 Miniature Circuit Breaker
- 20A
- 3 Pole
- Unit Mount
Square D
QOU3201021
Miniature Circuit Breaker
Brand
Square D
SKU
QOU3201021
Quantity
Shop with Confidence
Add an extra year of protection in your cart.
Square D QOU3201021 - 20A 3 Pole Miniature Circuit Breaker
New
Quantity
Similar Items
40A 3 Pole Miniature Circuit Breaker
50A 3 Pole Miniature Circuit Breaker
20A 3 Pole Miniature Circuit Breaker
Description
Engineered for advanced control applications, the Square D QOU3201021 is a 20A, 3-pole miniature circuit breaker equipped with a factory-installed shunt trip mechanism. This allows the breaker to be tripped remotely via an external voltage signal. It utilizes a flexible unit-mount design compatible with DIN rails and OEM enclosures. It delivers a 10 kAIC interrupt rating at 240VAC, includes Visi-Trip status indication, and features reversible box lugs for simplified wiring.Specifications
| Brand | Square D |
|---|---|
| Part Number | QOU320-1021 |
| Series | QOU |
| Amperage | 20A |
| Poles | 3 |
| Mounting Style | Unit Mount |
| Voltage | 240VAC, 120/240VAC, 48VDC |
| Phase | 3 |
| AIC Rating | 10kA @ 240VAC, 10kA @ 120/240VAC, 5kA @ 48VDC |
| Frame Type | QOU |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | DIN Rail Systems, OEM Panels, Control Panels, Enclosures |
| Wire Gauge | 14-2 AWG (Al/Cu) |
| Max Wire | 2 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Mounting Feet, Padlock Attachment |
|---|---|
| Accessories | Shunt Trip |
| Standards | CSA C22.2 No. 5, IEC 60947-2, NEMA AB 1, UL 489 |
| Approval | CSA, HACR, IEC, UL |
| Temp Rating | 40C |
Product FAQs
6 answersWhat does the 1021 suffix mean on the QOU3201021 part number?
The 1021 suffix designates a factory-installed shunt trip. This allows the breaker to be opened remotely via an external 120VAC to 240VAC control signal, which is commonly used in advanced control panels and emergency shutdown systems.
How is the QOU3201021 secured within an enclosure?
As a unit-mount breaker, it does not plug into a traditional load center bus. Instead, it features a cable-in, cable-out design and can be surface-mounted, flush-mounted, or attached to a standard DIN rail using the appropriate mounting hardware.
What type of conductors can be terminated on this breaker?
The integrated box lugs are rated for both aluminum and copper wire. They accept conductor sizes ranging from 14 AWG to 2 AWG, providing flexibility for various field wiring requirements.
How does the Visi-Trip feature assist with maintenance on this breaker?
The Visi-Trip indicator provides a highly visible red flag when the breaker trips due to an overcurrent condition or a remote shunt trip signal. This allows electricians to quickly identify the faulted circuit in a crowded control panel.
Can this breaker be used in direct current control circuits?
Yes, in addition to its standard AC ratings, this breaker is UL listed for DC applications up to 48VDC. It provides a 5kA interrupting capacity for DC control panels and battery systems.
Is the QOU3201021 suitable for 3-phase equipment?
Yes, this is a 3-pole breaker designed for 3-phase applications. It features an internal common trip mechanism that ensures all three poles open simultaneously during a fault or when the shunt trip is activated.
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.
Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 106 reviews.
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.
Search
Rating
106 reviews
- HLHOMETIGO L.Verified BuyerReviewingSquare D QOU260 - 60A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/7/26Good thing
i recommend this for you
- RGRobert G.Verified BuyerReviewingSquare D QOU340 - 40A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/3/26Circuit 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.
- THTiffany H.Verified BuyerReviewingSquare D QOU115 - 15A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/28/26Will use Super Breakers again
Arrived in a timely manner. Exactly what we needed for a job.
- CSCary S.Verified BuyerReviewingSquare D QOU250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/12/26Just what I ordered
Just what I needed for dock pedestal
- MHMark H.Verified BuyerReviewingSquare D QOU250VH - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars8/11/26Square D QOU250VH - 50A 2 Pole Miniature Circuit Breaker
Was just what I expected!