We are going to be putting a dedicated 20A/12-2 wire receptacle in the basement for our treadmill. When we are putting in the new 20A breaker, we are concerned with what is 'live' in the service panel. I know the 2 service wires are hot before the main but is there a chance anything else may be live? Anything to watch out for? Luckily our box has a separate cover so we can be sure not to touch the service wires, however I remember someone saying (no idea where) that the ground or neutral buses could be hot - is this true? And how can I mitigate/test for this?

Any help would be appreciated.

Chrissy :)

Eaton Cutler-Hammer panel
Model: CPM120
120/125A

With the Main OFF, It is extremely more unlikely that a Neutral or Ground to become Live.
If you remove any neutral that has a Load on it, the Neutral willl become live by going from the Hot wire through the load and out the unconnected neutral.
Just hook up neutral, and ground, then hook to breaker.
Don't touch anything you don't need too. A Meter or tester can be sure there is no power.

Here you go: Replacing a Breaker in Your Panel

Basically don't touch the wires entering the main breaker. Use the one hand rule.

With the main ON, removing neutrals can be dangerous to you and your appliances.

The large wires feeding the Main breaker are live, as you mentioned. On a properly wired and operating system, neither the Neutral or the ground should be live.

Before you open any panel, shutting off the Main breaker should make the panel safe, again, with exception to the lugs on the Main.

Before touching any part that could be live, must use a voltage tester to be sure voltage is truly off. We always use the Neutral and/or ground as a reference for one test probe, and use the other probe to check any exposed terminal.

I, personally, never recommend using the non-contact type of voltage tester. I probably should for DIY'ers, but I had an experienced man get severely shocked using one of those, even after he tested the tester on a known live circuit.


I included a photo of what I believe is your panel. I see the two covers, one for the main. With the bottom cover off and the Main off, you should be fine. Be sure to test anyway, as you never know if a breaker fails to open on both legs.

Wow! Thanks everyone for the quick responses. I really appreciate all your help - it never hurts to ask.

Happy NY :)

Chrissy

p.s. We have a contact tester - but TKRussell, you have just solidified my decision to not get a non-contact one. Yikes!