Installing a Subpanel:
Electrical Subpanel Safety Tips: What You Can and Can't Touch When Installing Circuit Breakers

Working in any electrical panel can be extremely dangerous. Find out what precautions to take when installing your subpanel.


The subpanel that Brian is working on has been newly added to power a garage shop.

It has NOT been connected to the main panel yet and therefore there is absolutely NO threat of electrocution. This is why Brian is not concerned with touching the contacts inside the subpanel with his fingers. We should have asked him to point with an insulated screwdriver.

When working on any type of electrical panel that is connected to a power supply, always err on the side of caution. Use a volt meter to check that the wires and bus bars are not energized.

Working Safe in an Electrical Subpanel

Before you add or repair any electrical cicuits in a home, you should be familiar with the layout of the main panel or subpanel that feeds power to the house. In this video, electrician Brian Walo gives a quick overview of where the power enters a subpanel, and what you need to turn off to safely connect or disconnect a circuit breaker.

This is a free companion video to our How To install a Subpanel member video series, which shows all the steps you'll need to get power to your new kitchen, garage workshop, finished basement, or any other remodel or addition.

Video transcript:

Save your life instead of saving time

You really shouldn’t be working in a live panel no matter what. It takes two seconds to turn off the main breaker. However, that doesn’t give you complete freedom to do whatever you want in here; there are still some dangerous parts. In a main panel, where you’ve got a main circuit breaker and some large wires coming in, even if you shut off the breaker, the two main poles are still going to be carrying electricity. If the main breaker were on, all of the exposed stabs for the bus bar are all going to be carrying electricity. So you’re not going to want to touch any of that. The neutral is also a potential shock point if the power is on. Try to avoid touching any of the incoming service lines.

Breakers should cut the power, but always double-check

Now, once the main circuit breaker is off, all of thes bus bars have been de-energized, but always test to be sure. If you happen to strike one of the bars after the main cicuit is off, you’ll actually be OK. Same goes for the terminals on the breakers themselves; they’re like light switches. When one is on, the connection is hot. When you turn it off, it’s dead.


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Brian Walo

Brian Walo
Brian Walo is a licensed electrician in Mount Pleasant, SC. When he’s not designing additions or renovations, he enjoys fishing, working on handmade guitars and furniture, and honing his culinary skills. Brian lives with his wife, Val, and their daughter, Grace.


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