This is a panel in a room built off my garage. The 220-V calbe on the left is the feed, and there are three or four 120-V cables coming out, as well as at least one more 220-V coming out.

It looks to me like the 220-V was converted to 120 by connecting one wire to one side of the 220-V and the other to the bus bar.

Is this standard practice, or is this a jury rig?

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    Pictures? Please
    – Kris
    Oct 6 at 21:56
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    Pictures are really needed of the panel. If it is as you say, then you need to turn off the power, but I think you might mistaken on what you are seeing. We need pictures.
    – crip659
    Oct 6 at 22:15
  • 240V & 120V; 220V & 120V would be a problem and also have a 100V leg, and 220/110V hasn't been the case for decades in the US.
    – Ecnerwal
    Oct 6 at 23:13
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    You can edit your question, then use the "mountains and moon" icon above the edit window to insert pictures. Alternately, upload them to Imgur.com (StackExchange's partner image hoster) OR Google album or Microsoft album or whatever, edit in the URL or give it in a comment... and senior editors will edit them into the question. Oct 6 at 23:46
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    In case you're wondering about the 110V/220V thing, it took until Edison/Westinghouse/Tesla's "War of the Currents" was settled before electricity became a mass media sensation. By this time, Edison had made two voltage bumps (to 110V) to increase system capacity. So "110V/220V" stuck in the public consciousness like "Xerox" or "Google". It's actually been 240V since WWII. Oct 6 at 23:53

It's hard to divine what you're asking, especially without pictures, however...

The supply feed into a 240v panel comes in as 2 hots, a neutral and a ground. Each hot is connected to its own lug in the panel, usually one on each side. You get 120v by plugging a single-space breaker into a slot and that connects the breaker to one phase of the 240v feed, giving you 120v. If you need 240v to an outlet somewhere, you plug a double-space, 240v breaker into the appropriate pair of slots, and that connects to both 120v phases, giving you 240v at the destination.

Since this seems like it's a sub panel, not the main feed directly from the meter, the neutral should go to a lug that connects to a neutral buss bar, and the ground should go to a different lug that connects to a separate ground buss bar. In a sub-panel, neutral and ground should never be electrically connected.

It's highly likely that your panel was wired correctly, but again without a picture of your actual wiring nobody can be 100% certain.

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