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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 N400M) is a 400-amp, three-phase accessory for Square D L-Frame Panelboards. It features a 400A/L frame size and is compatible with the LHL circuit breaker series. This…

SKU 3G-OTH-722196

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
N400M
Type
For Use With Square D L-Frame Panelboards
Amps
400
Phase
Three
Includes
(1) Screw Set
Frame Size
400A/L
For Use With
Square D L-Frame Panelboards
Accessory Type
Panelboard Main Breaker Kit
Compatible Circuit Breaker Series
LHL
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 N400M) is a 400-amp, three-phase accessory for Square D L-Frame Panelboards. It features a 400A/L frame size and is compatible with the LHL circuit breaker series. This kit includes one screw set for installation.

Frequently Asked Questions

What is the Square D N400M panelboard main breaker kit used for?

The Square D N400M panelboard main breaker kit is used as a 400-amp, three-phase main breaker accessory for Square D L-Frame panelboards. It integrates with the LHL circuit breaker series to provide overcurrent protection and a service-disconnect point in commercial and industrial power-distribution systems.

What are the specifications of the Square D N400M main breaker kit?

The Square D N400M main breaker kit is rated 400 amps, three-phase, with a 400A/L frame size. It is designed for use with Square D L-Frame panelboards and is compatible with the LHL circuit breaker series. The kit includes one screw set for installation.

Where to buy the Square D N400M panelboard main breaker kit worldwide?

3G Electric supplies the Square D N400M panelboard 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 on this Square D accessory.

How to install the Square D N400M main breaker kit?

Install the Square D N400M main breaker kit by first de-energizing the panelboard. Mount the kit into the designated L-Frame panelboard opening, secure it with the included screw set, and connect the line and load conductors per the manufacturer's wiring diagram. 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 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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