Square D QOB340VH1021 Miniature Circuit Breaker
- 40A
- 3 Pole
- Bolt-On
Quantity
Square D QOB340VH1021 - 40A 3 Pole Miniature Circuit Breaker
New
Quantity
Description
Integrating a 120/208/240VAC shunt trip accessory, this 40A miniature breaker allows for remote circuit interruption. The three-pole configuration is ideal for complex commercial and industrial safety systems requiring automated disconnects. It mounts firmly into Square D NQ and NQOD panelboards using a secure bolted connection. This ensures maximum stability for critical branch circuits. With a 22kAIC rating, the unit also includes the standard Visi-Trip flag for quick status checks.Specifications
| Brand | Square D |
|---|---|
| Series | QOB |
| Amperage | 40A |
| Poles | 3 |
| Mounting Style | Bolt-On |
| Voltage | 120VAC, 240VAC, 120/240VAC |
| Phase | 3 |
| AIC Rating | 22kA @ 120VAC, 22kA @ 240VAC, 22kA @ 120/240VAC |
| Frame Type | QOB |
|---|---|
| Terminal Type | Box Lugs |
| For Use With | NQ Panelboards, NQOD Panelboards |
| Wire Gauge | 8-2 AWG (Cu/Al) |
| Max Wire | 2 AWG |
| Min Wire | 8 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, UL 489, HACR |
| Approval | CSA, UL |
| Temp Rating | 40C |
| Construction Features | HACR Rated, Visual Trip Indicator, High Interrupting Capacity |
Product FAQs
6 answersWhich Square D panelboards accept the QOB340VH1021 circuit breaker?
This QOB frame breaker is designed specifically for bolt-on installation in Square D NQ and NQOD series panelboards. It will not fit in standard QO load centers, which require plug-on breakers.
What does the 1021 suffix mean on the QOB340VH1021 catalog number?
The 1021 suffix indicates the breaker comes with a factory-installed 120/208/240VAC shunt trip accessory. This allows the breaker to be tripped remotely by an external control signal, commonly used in emergency stop or automated disconnect systems.
How many panel spaces does the QOB340VH1021 require?
Because it includes a factory-installed shunt trip accessory, this 3-pole breaker requires four total panel spaces for installation.
What does the VH designate in the QOB340VH1021 part number?
The VH indicates that this is a high-interrupting breaker. While standard QOB breakers are typically rated at 10kAIC, the VH version provides an upgraded 22kAIC interrupting rating at 120/240VAC.
Does the QOB340VH1021 feature a tripped circuit indicator?
Yes, this breaker includes Square D's signature Visi-Trip indicator. When the breaker trips, the handle moves to a center position and a red indicator appears in a window on the case for quick identification.
What is the ambient temperature rating for the QOB340VH1021?
The thermal-magnetic trip element in this breaker is calibrated for use at a 40 degrees Celsius (104 degrees Fahrenheit) ambient temperature.
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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