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SQUARE D Miniature Circuit Breaker: 40 A, 120/240V AC, Three Phase, 22kA at 120/240V AC - QO Series, Plug-In Square D Miniature Circuit Breakers
SQUARE DQO Series, Plug-In Square D Miniature Circuit Breakers

SQUARE D Miniature Circuit Breaker: 40 A, 120/240V AC, Three Phase, 22kA at 120/240V AC

The SQUARE D QO340VH is a three-pole, 40 A miniature circuit breaker from the QO Series, designed for plug-in installation in QO Load Centers and NQ Panelboards. It is rated for 120/240V AC with a maximum AIR rating…

SKU 3G-OTH-21931

Brand
SQUARE D
Item
Miniature Circuit Breaker: 40 A, 120/240V AC, Three Phase, 22kA at 120/240V AC
Category
QO Series, Plug-In Square D Miniature Circuit Breakers
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

SQUARE D
Manufacturer Part Number
QO340VH
Type
Three Phase, 22kA at 120/240V AC
AC
120/240V
Amps
40 A
Phase
Three
Poles
3
For Use With
QO Load Centers and NQ Panelboards
Max. AIR Rating
22kA at 120/240V AC
AC Voltage Rating
120/240V AC

Technical Documents

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

Product Description

The SQUARE D QO340VH is a three-pole, 40 A miniature circuit breaker from the QO Series, designed for plug-in installation in QO Load Centers and NQ Panelboards. It is rated for 120/240V AC with a maximum AIR rating of 22kA at 120/240V AC. This three-phase breaker provides overcurrent protection for compatible Square D electrical distribution equipment.

Frequently Asked Questions

What is the SQUARE D QO340VH miniature circuit breaker used for?

The SQUARE D QO340VH is a three-pole, 40 A miniature circuit breaker used for overcurrent protection in three-phase electrical systems. It is designed for plug-in installation in QO Load Centers and NQ Panelboards, providing reliable protection for commercial and industrial power distribution applications.

What are the specifications of the SQUARE D QO340VH?

The SQUARE D QO340VH is a 40 A, three-pole miniature circuit breaker rated for 120/240V AC, three-phase. It has a maximum AIR rating of 22kA at 120/240V AC. This QO Series breaker is designed for plug-in use with QO Load Centers and NQ Panelboards, offering robust overcurrent protection.

Where to buy the SQUARE D QO340VH worldwide?

You can source the SQUARE D QO340VH through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we provide reliable sourcing for Square D circuit breakers.

How to install the SQUARE D QO340VH circuit breaker?

To install the SQUARE D QO340VH, ensure the panel is de-energized. Align the breaker's plug-in base with the bus bar in a compatible QO Load Center or NQ Panelboard, then press firmly until it snaps into place. Verify proper torque on connections per manufacturer guidelines. Always follow local electrical codes.

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 qo series, plug-in 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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