How to Wire a 200 Amp Subpanel


Wiring a 200 amp subpanel can seem intimidating, but it is absolutely a do-it-yourself project if I take my time and follow proper safety precautions. A subpanel provides additional circuit capacity and allows circuit isolation for additions or renovations. I'll walk through the complete process step-by-step to help demystify subpanel wiring.

Reasons for Installing a 200 Amp Subpanel

There are several common reasons I may need to install a 200 amp subpanel:

Subpanel Basics

Before getting into the step-by-step process, it helps to understand some key subpanel terminology and components:

Main Service Panel vs Subpanel



Electrical Permit

Most jurisdictions require an electrical permit for subpanel installation. I'll need to research permit requirements for my area and submit plans for review. The inspector will check my work after completion before giving final approval.

Tools and Materials

I'll need to gather the following tools and materials:



Step-by-Step Installation

With tools & materials gathered, I'm ready to install the subpanel. I'll follow standard safety procedures and de-energize circuits before working. Here is an overview of the full installation process:

1. Choose Subpanel Location

Ideal location is a garage, basement, or utility area. I should aim for:

2. Mount Subpanel

Securely fasten panel to wall studs if possible:

3. Install Grounding

Subpanel must be properly grounded:

4. Run Feed Conduit

Run 1" feed conduit from main to subpanel:

5. Pull Feed Wires

Carefully pull THHN wires through conduit:

6. Connect Feed Wires

Land and terminate feed wires securely:

7. Install Main Breaker

Install main breaker in subpanel:

8. Install Branch Breakers

Add circuit breakers for branch circuits:

9. Connect Branch Circuits

Connect lighting, outlet, and appliance circuits:

10. Inspect and Energize

Call inspector to review work before energizing:

Following proper planning, safety procedures, and this step-by-step guide, I can successfully install a 200 amp subpanel to expand my home's electrical capacity. Take it slowly and be meticulous for best results. Stay safe by de-energizing all circuits before working.