jmann
New member
- Location
- Maine, USA
Here's my situation: My father-in-law has a workshop, totally separate from his house. The shop and house are fed separately from the same meter. (Meter --> 200amp disconnect --> junction box where the two hot wires and neutrals are split to feed the house and shop separately. The existing feeders are direct buried, not in conduit. There is a grounding conductor at the pole.) This has been the setup since the 80s.
Recently, someone drove an excavator over the lawn and caused the shop feeder to fail. Now, he's going to have the feeder to the shop replaced with conduit and new feeder cables. I am helping advise him, and a local electrician is going to do the work. I'm trying to give him a clear sense of what needs to be done (and thus how much it's likely to cost.)
Here's my question: The old feeder had 3 conductors, but I assume that the new feeder should be 4-wire, including a separate ground conductor, because the neutral and ground are bonded at the disconnect on the pole. (I wired my own house last year, and this is what we did, following the instructions of our local utility.)
If that's the case, I am assuming that the grounds and neutrals in the shop subpanels must also be separated. In the existing setup, the neutrals and grounds are on the same bus bar. Am I correct about this?
Lastly, is there any safety concern with upgrading to 4 wire feeder to the shop while the feeder to the house is still the older 3-wire? (I can't think of a scenario in which this poses a danger, but I want to make sure.)
Recently, someone drove an excavator over the lawn and caused the shop feeder to fail. Now, he's going to have the feeder to the shop replaced with conduit and new feeder cables. I am helping advise him, and a local electrician is going to do the work. I'm trying to give him a clear sense of what needs to be done (and thus how much it's likely to cost.)
Here's my question: The old feeder had 3 conductors, but I assume that the new feeder should be 4-wire, including a separate ground conductor, because the neutral and ground are bonded at the disconnect on the pole. (I wired my own house last year, and this is what we did, following the instructions of our local utility.)
If that's the case, I am assuming that the grounds and neutrals in the shop subpanels must also be separated. In the existing setup, the neutrals and grounds are on the same bus bar. Am I correct about this?
Lastly, is there any safety concern with upgrading to 4 wire feeder to the shop while the feeder to the house is still the older 3-wire? (I can't think of a scenario in which this poses a danger, but I want to make sure.)
