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SQUARE D Miniature Circuit Breaker: 90 A, 120/240V AC, Three Phase, 10kA at 120/240V AC - QOU Series, Unit-Mount Square D Miniature Circuit Breakers
SQUARE DQOU Series, Unit-Mount Square D Miniature Circuit Breakers

SQUARE D Miniature Circuit Breaker: 90 A, 120/240V AC, Three Phase, 10kA at 120/240V AC

The SQUARE D QOU390 is a 90 A, three-phase miniature circuit breaker from the QOU Series, rated for 120/240V AC with a maximum AIR rating of 10kA at 120/240V AC. This unit-mount breaker is designed for use with…

SKU 3G-OTH-23311

Brand
SQUARE D
Item
Miniature Circuit Breaker: 90 A, 120/240V AC, Three Phase, 10kA at 120/240V AC
Category
QOU Series, Unit-Mount Square D Miniature Circuit Breakers
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Technical Specifications

SQUARE D
Manufacturer Part Number
QOU390
Type
Three Phase, 10kA at 120/240V AC
AC
120/240V
Amps
90 A
Phase
Three
Poles
3
For Use With
Heating
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 QOU390 is a 90 A, three-phase miniature circuit breaker from the QOU Series, rated for 120/240V AC with a maximum AIR rating of 10kA at 120/240V AC. This unit-mount breaker is designed for use with heating applications and features three poles.

Frequently Asked Questions

What is the SQUARE D QOU390 miniature circuit breaker used for?

The SQUARE D QOU390 is a 90 A, three-phase miniature circuit breaker designed for heating applications. It provides overcurrent protection in commercial and industrial electrical systems where 120/240V AC, three-phase power is required.

What are the specifications of the SQUARE D QOU390?

The SQUARE D QOU390 is a 90 A, three-pole miniature circuit breaker rated for 120/240V AC, three-phase. It has a maximum AIR rating of 10kA at 120/240V AC and is part of the QOU Series. It is intended for use with heating equipment.

Where to buy the SQUARE D QOU390 worldwide?

3G Electric supplies the SQUARE D QOU390 miniature circuit breaker worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us to source this breaker for your project.

How to select the right SQUARE D QOU series breaker for heating?

Select a SQUARE D QOU series breaker based on your system's voltage, current rating, and phase configuration. For heating applications, ensure the breaker's amp rating matches the load and that the voltage rating (e.g., 120/240V AC) and pole count align with your panel.

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 qou series, unit-mount 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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