Considerations When Planning An Electrical Sub Panel
How to Plan for a Sub Panel Installation: Planning the right amperage and cabling for a sub-panel used in a basement, garage and other locations.
Planning any Electrical Sub-Panel Must Include a 4-Wire System
Electrical Question: I have two 150 amp service panels on separate feeds from the power company.
- The first serves my lighting and service outlets including 220 circuits for my range and dryer.
- The second has 2 60 AMP circuits and 2 50 amp circuits for resistance heating used several years ago.
- I also have circuits for my water heater and Air Conditioning and Heat Pump.The house was originally all electric.
- Since I converted to gas several years ago, the two 50 amp circuits and one 60 amp have no electrical load. These four circuits are all set up with a ground return cabling (i.e. two hots and a ground, no neutral).
- Can I use the spare 60 amp cabling to feed a 60 amp sub-panel in my basement to service my circuits down stairs including some additional service outlets.
- I would have to connect the ground and neutral bars in the panel to utilize the heavy cable back to the main panel. The ground for the two main panels are connected at the panels.
- The wiring is 6 AWG aluminum.
Background: Bob, a Homeowner from Fairfax county, Virginia
Thanks for your electrical wiring question Bob.
How to Plan for a Sub Panel Installation
Planning the right amperage and cabling for a sub-panel used in a basement, garage and other locations
- Panels supplying 240 volts that are fed from the main electrical panel require a 4-wire feeder consisting of two hots, one neutral and a ground.
- All wires must be sized for the intended loads and the circuit breaker must be properly sized to provide protection for the size and type of the wire or cable.
- The neutral and the ground must be separately terminated and not bonded together at any sub-panel or the proposed electrical panels you wish to add.
Sub-Panel Electrical Wiring for the Home
Electrical sub-panel wiring considerations for the home complete with pictures. Careful planning for your Sub-Panel with immediate and future load considerations will help you understand how to size your Sub-Panel. This information will help as you consider a Sub-Panel and its size.
House Wiring Circuits and Circuit Breakers
This article looks at common 120 volt and 240 volt house wiring circuits and the circuit breakers that are installed identifying the types and amperage sizes used in most homes.
Electrical Panel Circuit Listing
Electric Circuit Listing
The size of the home electrical service panel is designed by calculating the square footage of the home and factoring in the code requirements for the electrical circuits that are required.
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Electrical panel 4-wire cable, electrical wire, ground and neutral, sub panel
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Be Careful and Be Safe - Never Work on Energized Circuits!
Consult your Local Building Department about Permits and Inspections for all Electric Wiring Projects.