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SQUARE D 9421LB7 Door Mount Operating Mechanism, 125 A, 3 Poles - Square D Circuit Breaker Handles & Operators
SQUARE DSquare D Circuit Breaker Handles & Operators

SQUARE D 9421LB7 Door Mount Operating Mechanism, 125 A, 3 Poles

The SQUARE D Door Mount Operating Mechanism (MPN 9421LB7) is a circuit breaker handle and operator accessory designed for use with NEMA 1, 3, 3R, 4, 4X, and 12 enclosures containing PowerPact(R) B Circuit Breakers…

SKU 3G-OTH-19343

Brand
SQUARE D
Item
9421LB7 Door Mount Operating Mechanism, 125 A, 3 Poles
Category
Square D Circuit Breaker Handles & Operators
Available to Order
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Technical specs
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Local availability & support — the Philippines

Delivery
5–8 business days door-to-door; Bureau of Customs clearance typically 2–4 business days.
Payment
Invoicing in PHP or USD. Bank transfer and corporate PO accepted.
Ships to
Manila, Quezon City, Cebu, Davao, Batangas

Technical Specifications

SQUARE D
Manufacturer Part Number
9421LB7
Amps
125 A
Poles
3
For Use With
NEMA 1, 3, 3R, 4, 4X, 12 Enclosures with PowerPact(R) B Circuit Breakers
Accessory Type
Door Mount Operating Mechanism
Number of Poles
3

Technical Documents

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

Product Description

The SQUARE D Door Mount Operating Mechanism (MPN 9421LB7) is a circuit breaker handle and operator accessory designed for use with NEMA 1, 3, 3R, 4, 4X, and 12 enclosures containing PowerPact(R) B Circuit Breakers. This 3-pole, 125 A accessory provides a door-mounted operating mechanism for Square D circuit breakers.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the Square D 9421LB7 door mount operating mechanism used for?

The Square D 9421LB7 is a door-mounted operating mechanism for PowerPact B circuit breakers. It allows external on/off control of a 3-pole, 125 A breaker housed in NEMA 1, 3, 3R, 4, 4X, or 12 enclosures, enabling safe operation without opening the enclosure door.

What are the specifications of the Square D 9421LB7?

The Square D 9421LB7 is a door mount operating mechanism rated for 125 A and 3 poles. It is designed for use with PowerPact B circuit breakers in NEMA 1, 3, 3R, 4, 4X, and 12 enclosures. The accessory type is a door mount operating mechanism, manufactured by Square D.

Where to buy the Square D 9421LB7 worldwide?

3G Electric supplies the Square D 9421LB7 door mount operating mechanism worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time; we source and deliver this Square D accessory globally.

How to install the Square D 9421LB7 door mount operating mechanism?

Install the Square D 9421LB7 by mounting it on the enclosure door per the manufacturer's instructions. Align the mechanism with the PowerPact B breaker handle, secure with provided hardware, and verify smooth operation. Always disconnect power before installation and 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 square d circuit breaker handles & operators. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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