Eaton Main Circuit Breaker Loa...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$3,622.16
Eaton Main Circuit Breaker Loadcenter, 400A, NEMA 1, 42-Circuit, Single-Phase

Eaton Main Circuit Breaker Loadcenter, 400A, NEMA 1, 42-Circuit, Single-Phase

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Model: BR4242B400S

In Stock (leaves warehouse same day if ordered before 3pm ET)

$3,622.16
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Eaton Main Circuit Breaker Loadcenter, 400A, NEMA 1, 42-Circuit, Single-Phase

The Eaton Main Circuit Breaker Loadcenter is a 400A, single-phase power distribution panel built for demanding residential and light commercial electrical systems. Configured with 42 circuits/spaces, a NEMA 1 enclosure rated for indoor surface mounting, and an included cover, this loadcenter delivers reliable, code-compliant power distribution backed by a UL Listed design (file E52977) and Eaton's 10-year limited warranty.

Key Features

  • Amperage Rating: 400A main circuit breaker rating supports high-capacity single-phase electrical service.
  • Circuit Capacity: 42 circuits and 42 spaces provide ample room for branch circuit expansion and future load additions.
  • NEMA 1 Enclosure: NEMA 1 rated enclosure designed for surface mounting in indoor, non-hazardous locations.
  • Durable Construction: Aluminum bus material offers reliable current-carrying performance within the loadcenter assembly.
  • Single-Phase Configuration: Engineered for single-phase power distribution in residential and light commercial applications.
  • Cover Included: Ships with a matching enclosure cover for a complete, ready-to-install assembly.
  • Interrupt Rating: 22 KAIC short-circuit interrupt rating supports safe operation under fault conditions.
  • Backed Warranty: Covered by Eaton's 10-year limited warranty for long-term peace of mind.

Certifications & Compliance

  • UL Listed, file E52977
  • NEMA 1 Rated Enclosure

Technical Specifications

  • Number of spaces: 42
  • Product Type: Load Center
  • Number of circuits: 42
  • Warranty: 10 year limited
  • Amperage Rating: 400 A
  • Phase: Single-phase
  • Mounting: Surface
  • Interrupt Rating: 22 KAIC
  • Bus Material: Aluminum
  • NEMA Rating: NEMA 1

Typical Applications

  • Residential Main Electrical Service Panels
  • Light Commercial Power Distribution
  • Single-Phase Branch Circuit Wiring
  • Panelboard and Load Center Upgrades
  • New Construction and Service Panel Renovation

Why Eaton?

Eaton loadcenters combine an aluminum bus, a NEMA 1 rated enclosure, and a 22 KAIC interrupt rating to deliver dependable, code-compliant power distribution for demanding electrical installations. Backed by UL Listing and a 10-year limited warranty, this 400A single-phase loadcenter is built for professionals who need reliable performance they can stand behind.

Manufacturer Resources

Product Specs

Product Width:
16 in
Cover Type:
Cover included
Amperage Rating:
400A
Product Length/Depth:
6.12 in
Number Of Spaces:
42
Product Height:
66.5 in
Product Type:
Load Center
Phase:
Single-phase
Number Of Circuits:
42
Warranty:
10 year limited
Mounting Method:
Surface
Interrupt Rating:
22 KAIC
Bus Material:
Aluminum
Nema Rating:
NEMA 1
Configuration:
NEMA 1 Enclosure
Certifications:
UL Listed file E52977
Department:
Electrical
Product Material:
Aluminum
Listing:
UL Listed
Product Group:
Power Distribution
Product Subgroup:
Panelboards & Load Centers
Product Weight:
96.25 lb
Product Length:
6.12 in

Eaton BR4242B400S – Frequently Asked Questions

1) Will the Eaton BR4242B400S fit in an outdoor meter/panel location?
No. The BR4242B400S ships in a NEMA 1 enclosure, which is indoor, non-hazardous locations only. Mount it on an interior wall surface. For an exterior wall or a wet location you need a rainproof (NEMA 3R) load center instead.
2) How much wall space do I need for a 400A Eaton BR load center?
Plan for a can that measures 66.5 inches high, 16 inches wide and 6.12 inches deep. That height matters on a retrofit: a 200A panel box is far shorter, so swapping up to this 400A unit usually means new wall opening and new conduit stub locations, not a drop-in into the old cutout. It is surface mount, so the 6.12 inch depth sits proud of the wall unless you frame a recess.
3) Can I use the Eaton 400A BR loadcenter on a three-phase service?
No. The BR4242B400S is a single-phase load center. If the service is 208Y/120 or 480Y/277 three-phase, you need a three-phase panelboard, not this unit.
4) Is 22 KAIC enough fault current rating for my 400A service?
The Eaton 400A BR loadcenter carries a 22 KAIC short circuit interrupt rating. Compare that against the available fault current the utility states at your service point, which is the number the inspector will ask for on a 400A service. If available fault current exceeds 22 kA at the panel, this enclosure is not rated for the location and you need a higher-interrupting panelboard.
5) Is the main breaker and the cover included, or do I order those separately?
The BR4242B400S is a main breaker loadcenter, so the 400A main is part of the unit, and a matching enclosure cover ships with it. What you still supply is the branch breakers, the service entrance conductors, grounding and bonding hardware, and any additional ground or neutral bar kit your layout calls for.
6) Does the Eaton BR4242B400S count as 42 usable breaker spaces?
Yes, 42 spaces and 42 circuits. Tandem breakers are not counted in that figure, so the real circuit count depends on what the panel accepts and on your local rules. For a 400A single-phase service feeding a large home or a light commercial tenant space, 42 spaces leaves room for future branch circuits without a subpanel.
7) Is the bus copper or aluminum on this Eaton 400A load center?
Aluminum bus. That is standard on Eaton BR series loadcenters. Torque the lugs to the values printed in the enclosure and use an antioxidant compound where your specification calls for it on aluminum terminations. If a project spec sheet demands copper bus, this unit will not meet it.
8) Will this Eaton loadcenter pass inspection as a service panel?
It is UL Listed under file E52977, which is the listing an AHJ looks for on a 400A single-phase service panel. The other two things they check are the enclosure rating for the location (NEMA 1, indoor only here) and that the 22 KAIC interrupt rating equals or exceeds the available fault current at the panel.
9) What part number should I give my supplier for the Eaton 400 amp 42-space main breaker panel?
BR4242B400S. That designation breaks down as BR series, 42 circuits, 42 spaces, main breaker, 400A, surface. It is single-phase with a NEMA 1 indoor enclosure and cover included.
How fast can I get the Eaton BR4242B400S delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Eaton BR4242B400S come with a warranty?
Absolutely. The Eaton BR4242B400S is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Eaton BR4242B400S?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
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