Square D QOB390VH-1021 Miniature Circuit Breaker
- 90A
- 3 Pole
- Bolt-On
Quantity
Square D QOB390VH-1021 - 90A 3 Pole Miniature Circuit Breaker
New
Quantity
Description
Engineered for advanced control, the Square D QOB390VH-1021 is a 3-pole, 90A miniature circuit breaker that delivers robust overcurrent protection. It is designed for commercial and industrial facilities requiring remote management. This breaker bolts into Square D NQ and NQOD panelboards, providing a vibration-resistant connection. It features a high interrupting rating of 22kAIC at 240V and includes a factory-installed 120/240VAC shunt trip for remote circuit disconnection.Specifications
| Brand | Square D |
|---|---|
| Series | QOB |
| Amperage | 90A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 240VAC, 120/240VAC |
| Phase | 3 |
| AIC Rating | 22kA @ 240VAC, 22kA @ 120/240VAC |
| Terminal Type | Box Lugs |
|---|---|
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 4 AWG-2/0 AWG (Al/Cu) |
| 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, Handle Tie, Handle Lock |
|---|---|
| Accessories | Shunt Trip |
| Standards | CSA C22.2 No. 5, HACR, RoHS, UL 489 |
| Approval | CSA, HACR, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, High Interrupting Capacity, Common Trip, Trip-Free Mechanism, Quick-Make/Quick-Break |
Product FAQs
5 answersWhich panelboards accept the QOB390VH-1021 circuit breaker?
This QOB series breaker is designed specifically for bolt-on installation in Square D NQ and NQOD panelboards. It is not compatible with standard QO load centers, which require plug-on breakers.
What does the -1021 suffix indicate on the QOB390VH-1021?
The -1021 suffix signifies that this breaker comes equipped with a factory-installed 120/240VAC shunt trip accessory. This allows the breaker to be opened remotely via a control signal.
What does the VH in the QOB390VH-1021 part number mean?
The VH designates a high interrupting rating. While standard QO and QOB breakers are typically rated at 10kAIC, this VH model provides a 22kAIC interrupting capacity at 120/240VAC.
What wire sizes are compatible with the lugs on this 90A breaker?
The box lug terminals accept wire gauges from 4 AWG up to 2/0 AWG. They are rated for use with either copper (Cu) or aluminum (Al) conductors.
How does the thermal-magnetic trip unit function on this breaker?
The fixed thermal-magnetic mechanism provides dual protection: a thermal element (Long-Time) that trips in response to sustained overloads, and a magnetic element (Instantaneous) that trips immediately during a short circuit.
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Reviews
Review summary
Customers rate this product 4.9 out of 5 based on 211 reviews.
- MLMike L.Verified BuyerReviewingSquare D QOB250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/9/26breaker orders
Breaker worked out great
Can not be happier with the quick shipping
- RCRichard C.Verified BuyerReviewingSquare D QOB380 - 80A 3 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/7/26Great price quick turn around
Thank you for getting me the breaker in a timely fashion
- DSDarren S.Verified BuyerReviewingSquare D QOB250 - 50A 2 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/5/26Airport taxi lighting
After contactor replacement we discovered bad breakers and were able to get replacements from Super Breakers in 2 days. THANK YOU SUPER BREAKERS..
- MRMiguel R.Verified BuyerReviewingSquare D QOB220GFI - 20A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/1/26Excellent
Excellent product and service
- MRMiguel R.Verified BuyerReviewingSquare D QOB230GFI - 30A GFCI Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars10/1/26Excellent
Excellent product and service