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SQUARE D Panelboard Main Breaker Kit: 400 Amps - Square D Main Breaker Kits
SQUARE DSquare D Main Breaker Kits

SQUARE D Panelboard Main Breaker Kit: 400 Amps

The Square D Panelboard Main Breaker Kit (MPN NQMB4LA) is a 400 Amp accessory for Square D NQ Panelboards, featuring a 400A/L frame size and compatibility with the LAL circuit breaker series. It includes one cover…

SKU 3G-OTH-722199

Brand
SQUARE D
Item
Panelboard Main Breaker Kit: 400 Amps
Category
Square D Main Breaker Kits
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Technical Specifications

SQUARE D
Manufacturer Part Number
NQMB4LA
Type
For Use With Square D NQ Panelboards
Amps
400
Includes
(1) Cover
Frame Size
400A/L
For Use With
Square D NQ Panelboards
Accessory Type
Panelboard Main Breaker Kit
Compatible Circuit Breaker Series
LAL
View Full Spec Sheet

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

Product Description

The Square D Panelboard Main Breaker Kit (MPN NQMB4LA) is a 400 Amp accessory for Square D NQ Panelboards, featuring a 400A/L frame size and compatibility with the LAL circuit breaker series. It includes one cover and is designed as a main breaker kit for use with Square D NQ Panelboards.

Frequently Asked Questions

What is the Square D NQMB4LA panelboard main breaker kit used for?

The Square D NQMB4LA is a 400 Amp main breaker kit designed for use with Square D NQ panelboards. It provides overcurrent protection and a main disconnect for the panelboard, enabling safe distribution of power in commercial and industrial electrical systems.

What are the specifications of the Square D NQMB4LA main breaker kit?

The Square D NQMB4LA is a 400 Amp panelboard main breaker kit with a 400A/L frame size. It is compatible with the LAL circuit breaker series and includes one cover. It is designed for use with Square D NQ panelboards.

Where to buy the Square D NQMB4LA main breaker kit worldwide?

3G Electric supplies the Square D NQMB4LA main breaker kit worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time.

How to install the Square D NQMB4LA main breaker kit?

Installation of the Square D NQMB4LA main breaker kit should be performed by a qualified electrician following the manufacturer's instructions. Typically, it involves mounting the kit into the NQ panelboard, connecting the line and load conductors, and securing the included cover. Always de-energize the panel before installation.

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 main breaker kits. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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