Engineered for commercial applications, the Square D QOB350GFI delivers 50A overcurrent and Class A ground-fault protection. This three-pole breaker features a 6mA trip threshold to safeguard personnel from electrical hazards. Designed for bolt-on installation, it mounts securely into Square D NQ and NQOD panelboards. The unit includes a pigtail neutral connection. Rated for 10kAIC at 208Y/120VAC, it utilizes the Visi-Trip indicator to easily identify tripped circuits.
Can I install this 3-pole GFCI breaker on a 3-phase load that does not use a neutral?
Yes [1.3.1]. The breaker can protect a 3-wire load without a load neutral connection. However, the white neutral pigtail on the breaker must still be connected to the panel neutral bar to power the internal ground fault circuitry.
Will the QOB350GFI fit in a standard QO residential load center?
No. This is a QOB bolt-on circuit breaker designed for commercial NQ and NQOD panelboards. Standard residential QO load centers require plug-on circuit breakers like the QO350GFI.
How many panel spaces does this breaker require?
As a 3-pole circuit breaker, it requires three standard spaces in your panelboard.
What level of ground fault protection does this circuit breaker provide?
It provides Class A ground fault protection for personnel, which means it will trip when it detects a ground fault current of approximately 4 to 6 milliamps (mA).
What is the plug-on equivalent for this bolt-on breaker?
If your electrical panel requires plug-on connections instead of bolt-on, the correct catalog number to order is QO350GFI.
Can I use this breaker for Equipment Protection (EPD) applications?
No. This model provides Class A personnel protection. If your application requires a 30mA equipment protection level, you must use a breaker with an EPD suffix instead of GFI.
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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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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
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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.