A staple for commercial power distribution, the QOB330 delivers dependable overload and short-circuit protection for 30-amp, three-phase circuits. This standard 10kAIC breaker utilizes proven thermal-magnetic trip technology to safeguard wiring from electrical faults. Designed to mount into Square D NQ and NQOD panelboards, the bolt-on connection ensures a tight, reliable fit. Maintenance is simplified by the integrated Visi-Trip window, which flashes a red flag when the breaker trips.
CSA C22.2 No. 5, UL 489, NEMA AB 1, HACR, RoHS, REACh
Approval
CSA, HACR, UL
Temp Rating
40C
Construction Features
Visual Trip Indicator, HACR Rated
Product FAQs
6 answers
Can I install the QOB330 in a standard Square D QO load center?
No. The QOB330 features a bolt-on connection designed exclusively for Square D NQ and NQOD panelboards. Standard QO residential and commercial load centers require plug-on breakers, not bolt-on.
How many panel spaces does the QOB330 require in an NQ or NQOD panelboard?
This 3-pole miniature circuit breaker occupies three standard 3/4-inch pole spaces.
What is the recommended tightening torque for the load terminals on the QOB330?
The pressure plate wire terminals should be tightened to 35.4 lb-in (4 N.m) for 14-8 AWG copper or aluminum conductors.
Are there alternate versions of this 30A breaker with higher short circuit interrupting ratings?
Yes. If your application requires more than 10kAIC at 240VAC, the QOB330VH provides 22kAIC, and the QHB330 provides 65kAIC.
Can I use the QOB330 on a 3-phase 208Y/120V electrical network?
Yes. It is rated for a maximum of 240VAC, making it fully compatible with 3-phase 208Y/120V solid-grounded Wye systems as well as 240V Delta configurations.
How can I quickly identify if the QOB330 has tripped in a busy electrical room?
This breaker includes the Square D Visi-Trip indicator. When the breaker trips due to an overload or short circuit, a bright red flag snaps into the window on the face of the breaker for immediate visual identification.
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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.
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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 4.9 out of 5 based on 205 reviews.
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Rated 4.9 out of 5 stars
Based on 205 reviews
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Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 3/11/26
Customers say these electrical breakers arrive exactly as ordered and work perfectly for their intended applications. They consistently praise the competitive pricing, which many report is significantly lower than local suppliers. Fast shipping and prompt delivery are frequently highlighted, with many receiving orders within days or even next-day delivery for urgent needs. The breakers arrive well-packaged and in excellent condition. Many reviews emphasize the company's extensive inventory availability, particularly for hard-to-find breakers. One customer experienced difficulty with order cancellation and was charged a restocking fee, which caused dissatisfaction.