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I need to replace the main breaker panel in a unit I'm renovating. (Single family home, not apartment, USA) Prior to tearing anything out I wanted to turn off power. (of course)

This community has "power distribution towers" that service 6 to 10 units. Each unit has a breaker that turns off power to that unit. I found the breaker for my unit, but it was labeled with a note, "one leg not working." In marker under the breaker.

I checked the voltage incoming at the main breaker and got 120 on one leg and 118 on the other. Is this a problem? I called the power company. They said it was an issue that I had to call an electrician about.

The only 240 appliance that is intact is the AC and it works fine. Is this really no issue, a 2V drop? Should I be getting 120V from both legs and the 118V is a sign that something is amiss?

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  • Can you post an image of the "power distribution tower"? I've never heard of such a thing (with accessible breakers) for single-family homes. Aug 11, 2023 at 4:05
  • @Jonathan Reinhart, I'm not working on that project every day. Next time I go back , I'll try to remember to take a pic.
    – RMDman
    Aug 11, 2023 at 12:33

1 Answer 1

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That small of difference is no cause for alarm. Even if the windings of the transformer were perfect, and the center neutral tap centered perfect on an ideal iron core then an uneven load by your neighbors that are served by the same transformer could effect voltage differences more than you have.

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  • Thank You. I would not normally give it a thought, but the note under the breaker made me think there was an issue.
    – RMDman
    Aug 10, 2023 at 12:08
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    I would guess the note is left over from a previous problem, one leg out would have drastic effects. Aug 10, 2023 at 12:13

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