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Square D QO31001021 Miniature Circuit Breaker
- 100A
- 3 Pole
- Plug-On
Square D
QO31001021
Miniature Circuit Breaker
Brand
Square D
SKU
QO31001021
Quantity
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Square D QO31001021 - 100A 3 Pole Miniature Circuit Breaker
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Quantity
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Description
Providing thermal-magnetic protection, this 100A, three-pole breaker includes a factory-installed shunt trip accessory rated for 120/208/240VAC operation. Designed for seamless integration, it installs into Square D QO load centers and NQ panelboards. The plug-on mounting ensures a reliable busbar connection. Rated at 10kAIC, it features the Visi-Trip indicator to quickly identify faults. The shunt trip allows the breaker to be opened remotely via an external signal.Specifications
| Brand | Square D |
|---|---|
| Part Number | QO31001021 |
| Series | QO |
| Amperage | 100A |
| Poles | 3 |
| Mounting Style | Plug-On |
| Voltage | 120VAC, 240VAC, 120/240VAC |
| Phase | 3 |
| AIC Rating | 10kA @ 120VAC, 10kA @ 240VAC, 10kA @ 120/240VAC |
| Frame Type | QO |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | QO Load Centers, NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 4 AWG - 2/0 AWG (Cu/Al) |
| Max Wire | 2/0 AWG |
| Min Wire | 4 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Available Options | Auxiliary Switch, Alarm Switch, Padlock Attachment |
|---|---|
| Accessories | Shunt Trip |
| Standards | CSA C22.2 No. 5, HACR, UL 489 |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | Visual Trip Indicator, HACR Rated |
Product FAQs
8 answersWhat does the 1021 suffix mean on the QO31001021 part number?
The 1021 suffix indicates that this model includes a factory-installed shunt trip accessory rated for 120V, 208V, or 240V AC. This allows the breaker to be tripped remotely by an external control signal.
How many panel spaces does the QO31001021 require?
This circuit breaker requires four standard QO panel spaces. The 3-pole breaker mechanism occupies three spaces, and the factory-installed shunt trip module occupies one additional adjacent space.
Can I field-install a shunt trip module onto a standard QO3100 breaker?
No. Square D QO and QOB shunt trip accessories must be factory-installed. You cannot add a shunt trip in the field, so you must purchase a breaker with the module pre-installed, such as this QO31001021.
How do I wire the shunt trip module on this breaker?
The shunt trip includes two terminals that accept 14 AWG to 12 AWG copper wire. To operate the remote trip function, apply a 120V to 240V AC signal across these terminals. The hot and neutral wires can be connected to either terminal.
What type of panelboards are compatible with the QO31001021?
This plug-on breaker is designed for 3-phase Square D QO load centers, NQ panelboards, and legacy NQOD panelboards. If your NQ or NQOD panel setup requires a bolt-on connection, you must use the QOB31001021 instead.
Can this shunt trip breaker be used with Ansul fire suppression systems?
Yes. It is commonly used in commercial kitchen exhaust hoods to interface with Ansul fire suppression systems. The fire system microswitch provides the 120V AC signal to the shunt trip terminals, instantly disconnecting power to the cooking equipment during an alarm event.
Will the 1021 shunt trip operate on a 24V DC control circuit?
No, the 1021 suffix designates a shunt trip coil rated specifically for 120V, 208V, or 240V AC. If your control circuit utilizes 12V or 24V AC/DC, you will need a QO breaker equipped with the 1042 suffix.
Does the QO31001021 feature a tripped circuit indicator?
Yes, it includes Square D's Visi-Trip indicator. When the breaker trips due to an overload, short circuit, or a remote shunt trip signal, a highly visible red flag appears in the breaker window to help quickly locate the tripped circuit in the panelboard.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 285 reviews.
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 6/13/26
Customers say these circuit breakers arrive quickly and work as described. Fast shipping and competitive pricing are frequently mentioned, with many noting same-day or next-day delivery. Users appreciate the wide inventory, particularly for hard-to-find older-style models unavailable locally. The products function reliably and arrive in good condition. Most customers report straightforward ordering and positive interactions. However, some experienced delivery delays or received incorrect items requiring reordering. A few noted concerns about condition upon arrival or customer service responsiveness.
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Rating
285 reviews
- GCGerard C.Verified BuyerReviewingSquare D QO130GFI - 30A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/21/26Great !
I could not find the breaker in hardwood stores. Superbreakers took car of it in a week.
- RHRoy H.Verified BuyerReviewingSquare D QO280 - 80A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/17/26Square D QO280 - 80A 2 Pole Miniature Circuit Breaker
Exactly as described
- KWKevin W.Verified BuyerReviewingSquare D QO120 - 20A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/15/26Great Price
Brand spanking new!
- CEchristopher e.Verified BuyerReviewingSquare D QO115PDF - 15A Dual Function Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/11/26My breakers
Had a hard time locating these breakers locally, when I did find 1 they wanted to charge me triple what superbreakers charged. Items delivered exactly when they said they would, were exactly what I ordered. Appreciated the ease of ordering, definitely my go to from this point on
- JCJerry C.Verified BuyerReviewingSquare D QO250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/8/26Great quality
No issues