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SQUARE D Miniature Circuit Breaker: 40 A, 120/240V AC, Single Phase, 10kA at 120/240V 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: 40 A, 120/240V AC, Single Phase, 10kA at 120/240V AC

The SQUARE D QOB Series Miniature Circuit Breaker (MPN QOB140) is a 40 A, single-phase, bolt-on circuit breaker rated for 120/240V AC with a maximum AIR rating of 10kA at 120/240V AC. Designed for use with Square D…

SKU 3G-OTH-23126

Brand
SQUARE D
Item
Miniature Circuit Breaker: 40 A, 120/240V AC, Single Phase, 10kA at 120/240V AC
Category
QOB Series, Bolt-On Square D Miniature Circuit Breakers
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Technical Specifications

SQUARE D
Manufacturer Part Number
QOB140
Type
Single Phase, 10kA at 120/240V AC
AC
120/240V
Amps
40 A
Phase
Single
Poles
1
For Use With
Square D NQOD Panelboards
Max. AIR Rating
10kA at 120/240V AC
AC Voltage Rating
120/240V AC
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SQUARE D Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SQUARE D QOB Series Miniature Circuit Breaker (MPN QOB140) is a 40 A, single-phase, bolt-on circuit breaker rated for 120/240V AC with a maximum AIR rating of 10kA at 120/240V AC. Designed for use with Square D NQOD Panelboards, this 1-pole breaker provides overcurrent protection in industrial electrical distribution systems.

Frequently Asked Questions

What is the SQUARE D QOB140 miniature circuit breaker used for?

The SQUARE D QOB140 provides overcurrent protection in industrial electrical distribution systems. It is a 40 A, single-phase, bolt-on breaker rated for 120/240V AC with a 10kA interrupting capacity, designed for use with Square D NQOD panelboards.

What are the specifications of the SQUARE D QOB140 circuit breaker?

The SQUARE D QOB140 is a 1-pole, 40 A, single-phase miniature circuit breaker rated 120/240V AC with a maximum AIR rating of 10kA at 120/240V AC. It is a bolt-on type for use with Square D NQOD panelboards.

Where to buy the SQUARE D QOB140 circuit breaker worldwide?

3G Electric supplies the SQUARE D QOB140 circuit breaker worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this Square D bolt-on breaker.

How to install the SQUARE D QOB140 circuit breaker?

Install the SQUARE D QOB140 by bolting it into a compatible Square D NQOD panelboard. Ensure the panel is de-energized, then torque the terminal screws to the manufacturer's specification. 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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