How to Wire a 200 Amp Electrical Service

Overview of Wiring a 200 Amp Service

Wiring a 200 amp electrical service can seem daunting, but it is an achievable DIY project if I take my time and follow proper safety precautions. A 200 amp service provides enough power for a medium to large sized home with all modern appliances and amenities.

To wire it properly, I will need to:

• Obtain the necessary permits and have the utility company install a new meter and run wire to the point of connection.
• Install a weatherproof service panel rated for 200 amps and containing enough spaces for all my circuit breakers.
• Run wire from the point of utility connection to the service panel. This will be 4/0 aluminum for a 200 amp service.
• Properly ground the service panel.
• Connect all ground and neutral wires.
• Run individual circuit wires to breakers and then to switches, outlets, and appliances.
• Clearly label all circuit breakers and wire connections.
• Have the completed work inspected before turning on power.

Working with the Utility Company

The first step in wiring a new electrical service is contacting my utility company. I will need to:

• Verify that they can provide 200 amps of power to my home.
• Schedule for them to install a new meter pan and run conductors to my point of connection.
• Obtain an electrical permit from the town for the utility side connection.
• Pay any fees the utility requires for the upgrade.

The utility will deliver 200 amps to my point of connection. This is commonly an electrical mast on the outside of the home where their lines can tie in.

I need to have all my own wiring up to the point of connection completed before the utility finishes their work. Coordinating with the utility company early is crucial to avoid delays.

Installing the 200 Amp Service Panel

The service panel is the central hub that my entire electrical system branches out from. Choosing the right 200 amp service panel is critical:

• It must have a main breaker for overcurrent protection.
• There should be enough spaces to accommodate all the circuit breakers I'll need.
• See if the panel can be expanded in the future by adding bolt-on sections.
• Select a sturdy, weatherproof enclosure for outdoor mounting.

Installation is straightforward but care must be taken to:

• Securely mount the panel to the home's exterior close to the point of connection.
• Leave at least 30 inches of clear space in front of it for access.
• Place the panel so the main breaker is on top and circuit breakers run down in order.

Running the Main Power Lines

From the point of utility connection, I will need to run thick 4/0 aluminum wires through conduit to connect to the main lugs of my service panel.

• Use an appropriate gauge of wire for a 200 amp service (4/0 aluminum).
• Run wires in steel or PVC conduit for protection.
• Use only copper for the ground wire from the main panel to the grounding rods.
• Clamp cables securely and provide drip loops where they enter the top of the panel.

The wires should be sized to handle the full 200 amp load in case all circuits were running at capacity simultaneously. Voltage drop is critical to consider over the length of these main power feeds.

Grounding and Bonding

Any 200 amp service must have proper grounding and bonding according to code in order to safely neutralize voltage in case of a fault. This involves:

• Running one or more grounding electrodes (ground rods) into the earth.
• Bonding the service enclosure to the grounding electrodes.
• Using thick copper wire for all grounding conductors.
• Ensuring ground wires connect to any outlet boxes and devices.

Maintaining continuity in the grounding system back to the main panel is paramount. I will need to test resistance to ensure grounding meets minimum requirements.

Running Individual Circuit Wiring

Now I can run wiring from the main service panel out to all locations needing power. Common guidelines include:

• Use the correct wire gauge for the amp load of the circuit. For 20 amp circuits this is often 12 AWG copper.
• Run wires in conduit for physical protection. EMT thinwall conduit is commonly used.
• Use only copper wire for standard 15 and 20 amp branch circuits.
• Don't overload circuits by putting too many outlets on one.
• Label all wires clearly at both ends.
• Allow slack in the wire when terminating connections.
• Follow box fill requirements when cramming multiple wires into a box.

I'll need to research the required circuits for a dwelling of my size, such as for the HVAC system, kitchen appliances, laundry, etc. Lighting and receptacles can be combined on general circuits.

Wrapping Up and Inspections

Before turning the power on, the final steps are:

• Double check all connections are tight and correct.
• Verify ground continuity and resistance.
• Pressure test wires to check for faults.
• Ensure all circuits are properly labeled.
• Call the building department for inspection of my completed work.

The inspectors will thoroughly examine my new 200 amp service install for compliance with the electrical code before giving the green light to energize the system.

Conclusion

While a major undertaking, with proper planning and adherence to electrical code, I can successfully install a new 200 amp service panel to power my home. This will provide me with abundant capacity for all my home's electrical needs now and far into the future. Paying close attention to details such as proper grounding, overcurrent protection, and neat workmanship will be key.