Please excuse me if there is a post that already answers this. I did look.
What I have:
A meter and disconnect switch provided by the CoOP hanging on a pole. It has lugs enough to provide 2 service connections. I'm the only one on the transformer.
One connection is in use to a 50/30/20 camper pedestal wired and working which I plan to keep. It is about 12 feet from the pole. I took it through conduit from the switch box knockout to well above grade in the pedestal. I dropped a grounding rod at this pedestal. It is working fine. GFI's in the camper test good. The surge protector on the camper is fine with it, I've seen it detect bad grounding in other places. As far as I know all is well with it. ( So, I've done this before just shorter. )
I read the voltage off the pole to be 124v hot to neutral. I didn't think to test the hot to hot last time I was there.
I have a 240v 50 amp camper with a automatic voltage booster on critical appliances.
I have a reasonable background in electrical work. 2 yrs of vocational school and DIY electrical in my own home for 15 yrs without starting a single fire.
I want to do:
I want to put in a second 50/30/20 camper pedestal about 500' from from the pole. This will go from the disconnect box to underground to the pedestal. My intention is to run wire with a good bit more capacity than the pedestal should require. I might want to add another pedestal in the same location in the future.
I expect to use aluminum direct bury wire. I've budgeted for 4/0,4/0,4/0 Alum so if my other assumptions are correct I can afford 4/0.
I've used a wire size calculator online and found:
3% voltage drop
4/0 AWG Alum
5% voltage drop
3/0 AWG Alum
5% voltage drop
2/0 AWG Alum
First just a sanity check with any advice you have. (Is 4/0 too much? that sort of thing)
More specific, can I run 3 direct bury conductors then ground the new pedestal at the pedestal or do I have to run 4 conductors? It's not a subpanel.
If my memory serves there is not a large grounding lug to connect the 4th conductor to the switch box. (I'm not at that property and won't be until after I buy the supplies)