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SQUARE D Rotary Operator: Rotary Operator, 125 A Amps, 3 Poles - Square D Circuit Breaker Handles & Operators
SQUARE DSquare D Circuit Breaker Handles & Operators

SQUARE D Rotary Operator: Rotary Operator, 125 A Amps, 3 Poles

The SQUARE D Rotary Operator (MPN 9421LB4) is a 3-pole circuit breaker handle and operator accessory designed for use with PowerPact B circuit breakers in NEMA 1, 3, 3R, 4, 4X, and 12 enclosures. It includes a long…

SKU 3G-OTH-19469

Brand
SQUARE D
Item
Rotary Operator: Rotary Operator, 125 A Amps, 3 Poles
Category
Square D Circuit Breaker Handles & Operators
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
9421LB4
Amps
125 A
Poles
3
Includes
Long Shaft
For Use With
NEMA 1, 3, 3R, 4, 4X, 12 Enclosures with PowerPact(R) B Circuit Breakers
Accessory Type
Rotary Operator
Number of Poles
3
Handle/Long Shaft
6 in

Technical Documents

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

Product Description

The SQUARE D Rotary Operator (MPN 9421LB4) is a 3-pole circuit breaker handle and operator accessory designed for use with PowerPact B circuit breakers in NEMA 1, 3, 3R, 4, 4X, and 12 enclosures. It includes a long shaft and is rated for 125 A. This rotary operator enables external manual operation of the breaker while maintaining enclosure integrity.

Frequently Asked Questions

What is the SQUARE D 9421LB4 rotary operator used for?

The SQUARE D 9421LB4 rotary operator is a circuit breaker handle accessory that allows external manual on/off control of a PowerPact B breaker without opening the enclosure door. It is rated for 125 A, 3 poles, and works with NEMA 1, 3, 3R, 4, 4X, and 12 enclosures.

What are the specifications of the SQUARE D 9421LB4?

The SQUARE D 9421LB4 is a 3-pole rotary operator rated for 125 A. It includes a 6 in handle/long shaft and is designed for use with PowerPact B circuit breakers in NEMA 1, 3, 3R, 4, 4X, and 12 enclosures. The accessory type is rotary operator, and the manufacturer part number is 9421LB4.

Where to buy the SQUARE D 9421LB4 worldwide?

3G Electric supplies the SQUARE D 9421LB4 rotary operator to customers 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 circuit breaker handle accessory.

How to install the SQUARE D 9421LB4 rotary operator?

Installation of the SQUARE D 9421LB4 rotary operator typically involves mounting the operator to the enclosure door and coupling it to the PowerPact B breaker's long shaft. Always follow the manufacturer's instructions and ensure the breaker is de-energized before installation. Proper alignment is critical for reliable operation.

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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