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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
Part Number
9421LB7
Category
Square D Circuit Breaker Handles & Operators
Available to Order
Also known as:9421LB7SQUARE D
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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

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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.

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 electrical panels — QO and QOB miniature circuit breakers for overcurrent protection in load centers and panelboards.
HVACR equipment — 8910 Series Type DPA definite purpose contactors for switching compressor and fan motor loads.
Industrial power distribution — J-Frame molded case circuit breakers for main and feeder protection in switchboards.
Residential ground-fault protection — QO and QOB GFI circuit breakers for kitchens, bathrooms, and outdoor circuits.
Motor control centers — definite purpose contactors for controlling pumps, fans, and other moderate motor loads.
OEM machinery — Square D circuit breakers and contactors for integration into control panels and equipment.
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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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