400 Amp Switchboard NEMA 1/3R
- 400A with 7 multi-voltage configurations
- UL 891 Certified & EUSERC Approved
- NEMA 1 or 3R enclosures, Siemens built
UL 891 Certified
EUSERC Approved
Siemens Approved OEM
DEI Power's 400 Amp Commercial Service Panels and Breaker Boxes include UL 891-certified panelboards, switchboards, meter mains, switchgear, and service entrance sections built with genuine Siemens components. Designed for commercial, industrial, and utility applications, these units support voltages from 120/240V to 480V and are available in NEMA 1 and NEMA 3R enclosures.
Talk to our product experts for custom solutions.
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A 400 amp commercial service typically requires 600 kcmil copper or 900 kcmil aluminum conductors per phase, though exact sizing depends on the installation distance, conduit fill, ambient temperature, and local NEC code requirements. Always consult a licensed electrician and your local authority having jurisdiction (AHJ) to confirm the correct wire gauge for your specific installation.
Talk to our experts for custom solutions and tailored guidance.
400A service panels deliver reliable branch circuit distribution and main service protection for offices and retail.
Heavy-duty switchboards and switchgear manage large electrical loads safely in manufacturing and processing plants.
UL 891-certified switchgear ensures uninterrupted power for hyperscale and enterprise data center operations.
EUSERC-approved meter mains and service entrance switchgear support utility substations and critical infrastructure projects.
Talk to our experts for custom solutions and tailored guidance.
Every panel and breaker box is built with genuine Siemens components as an approved OEM, ensuring code-compliant, precision-engineered assemblies you can depend on.
Our 50,000 sq. ft. Ontario, CA facility handles manufacturing in-house, enabling faster builds, fewer delays, and free shipping delivered to your jobsite in 3–5 business days.
From configuration guidance to post-installation assistance, our specialists provide clear documentation and expert support to keep your project on schedule and compliant.
Submit your project details and a DEI Power specialist will respond with pricing, configuration guidance, and lead time information.
For immediate assistance, feel free to give us a direct call at (866) 773-8050. You can also send us a quick email at sales@deipower.com.
For immediate assistance, feel free to give us a direct call at (866) 773-8050. You can also send us a quick email at sales@deipower.com.