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SQUARE D Miniature Circuit Breaker: 50 A, 120/208V AC, Three Phase, 10kA at 208/120V AC - QOB Series, Bolt-On Square D Miniature Circuit Breakers
SQUARE DQOB Series, Bolt-On Square D Miniature Circuit Breakers

SQUARE D Miniature Circuit Breaker: 50 A, 120/208V AC, Three Phase, 10kA at 208/120V AC

The SQUARE D QOB Series Miniature Circuit Breaker (MPN QOB350GFI) is a 50 A, three-phase, bolt-on breaker rated for 120/208V AC with a maximum AIR rating of 10kA at 208/120V AC. Designed for use with QO Load Centers…

SKU 3G-OTH-23185

Brand
SQUARE D
Item
Miniature Circuit Breaker: 50 A, 120/208V AC, Three Phase, 10kA at 208/120V AC
Category
QOB Series, Bolt-On Square D Miniature Circuit Breakers
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Technical Specifications

SQUARE D
Manufacturer Part Number
QOB350GFI
Type
Three Phase, 10kA at 208/120V AC
AC
120/208V
Amps
50 A
Phase
Three
Poles
3
For Use With
QO Load Centers and NQ Panelboards
Max. AIR Rating
10kA at 208/120V AC
AC Voltage Rating
120/208V AC
View Full Spec Sheet

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SQUARE D Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SQUARE D QOB Series Miniature Circuit Breaker (MPN QOB350GFI) is a 50 A, three-phase, bolt-on breaker rated for 120/208V AC with a maximum AIR rating of 10kA at 208/120V AC. Designed for use with QO Load Centers and NQ Panelboards, this 3-pole unit provides overcurrent protection in industrial electrical distribution systems.

Frequently Asked Questions

What is the SQUARE D QOB350GFI miniature circuit breaker used for?

The SQUARE D QOB350GFI provides overcurrent protection in industrial electrical distribution systems. It is designed for use with QO Load Centers and NQ Panelboards, handling 50 A at 120/208V AC three-phase. This bolt-on breaker is common in manufacturing plants, commercial buildings, and facility power panels.

What are the specifications of the SQUARE D QOB350GFI circuit breaker?

The SQUARE D QOB350GFI is a 3-pole, 50 A miniature circuit breaker rated for 120/208V AC three-phase. It has a maximum AIR rating of 10kA at 208/120V AC. This bolt-on unit is part of the QOB Series and is compatible with QO Load Centers and NQ Panelboards.

Where to buy the SQUARE D QOB350GFI circuit breaker worldwide?

3G Electric supplies the SQUARE D QOB350GFI miniature circuit breaker to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery for international orders. Contact us for pricing and lead time on this 50 A, three-phase breaker.

How to install the SQUARE D QOB350GFI bolt-on circuit breaker?

Install the SQUARE D QOB350GFI by ensuring the panel is de-energized, then bolt the breaker securely onto the bus bars of a compatible QO Load Center or NQ Panelboard. Torque terminals to manufacturer specifications for the 50 A, 120/208V AC circuit. Always follow local electrical codes and use proper personal protective equipment.

Used in

Common applications for SQUARE D
Commercial building electrical panels — Square D QO series plug-in circuit breakers for branch circuit protection
Industrial motor control centers — Square D QOB series bolt-on breakers in NQOD panelboards
Heating equipment installations — Square D QOU series unit-mount breakers for overcurrent protection
Outdoor electrical distribution — Square D L-Frame enclosures housing LAL/LHL breakers for 400 A service
Indoor facility power distribution — Square D Q-Frame enclosures with QBL/QDL breakers for 225 A circuits
Retrofit and replacement in existing Square D load centers — QO series breakers for 120/240V AC systems

SQUARE D Products

3G Electric supplies SQUARE D qob series, bolt-on square d miniature circuit breakers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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