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Ok so at some point I'm going to need to run another leg, until then. I have a main panel, 230v 80ft run to a we'll & pump, then a 900 ft run up to water tank and a pressure pump with another panel. Then a 120v leg off that that I want to plug an RV to. All 10 gauge 30 amps. With such a long run I have to much voltage drop for the 120 leg. Was thinking of a buck boost on the 120 leg but worried about to much voltage. Would a buck boost with a regulater work?
 
Ok so at some point I'm going to need to run another leg, until then. I have a main panel, 230v 80ft run to a we'll & pump, then a 900 ft run up to water tank and a pressure pump with another panel. Then a 120v leg off that that I want to plug an RV to. All 10 gauge 30 amps. With such a long run I have to much voltage drop for the 120 leg. Was thinking of a buck boost on the 120 leg but worried about to much voltage. Would a buck boost with a regulater work?
My friend the only way to avoid voltage drop is go up on your wire size. 900 feet that’s a long way for just 120vac. No transformer in the world is going to help you with voltage drop. I don’t know the size of the RV but normally they require a 50 amp 240 vac circuit. At 900 feet you would probably need 500 MCM wire installed in 3 inch pipe and that would be one h—- of a pull, you would need a truck to pull that. You better install plenty of pulling points if you are going to run wire 900 feet
 
My friend the only way to avoid voltage drop is go up on your wire size. 900 feet that’s a long way for just 120vac. No transformer in the world is going to help you with voltage drop. I don’t know the size of the RV but normally they require a 50 amp 240 vac circuit. At 900 feet you would probably need 500 MCM wire installed in 3 inch pipe and that would be one h—- of a pull, you would need a truck to pull that. You better install plenty of pulling points if you are going to run wire 900 feet
I have 240 running nine 800 of that 900 ft I should be able to Buck down to 120 the RV is an older one that only needs 30 amps I'm losing about 15-20 volts at the end
 
I have 240 running nine 800 of that 900 ft I should be able to Buck down to 120 the RV is an older one that only needs 30 amps I'm losing about 15-20 volts at the end
What size wire exist now ? for less than $ 100.00 you could add a sub panel and then you will have your 30 amp 120vac. All this depends on your wire size and do you have 4 wires 2 ungrounded conductors 1 neutral and 1 equipment ground
 
What size wire exist now ? for less than $ 100.00 you could add a sub panel and then you will have your 30 amp 120vac. All this depends on your wire size and do you have 4 wires 2 ungrounded conductors 1 neutral and 1 equipment ground
on the on the long leg of 240 there's only two Hots and a ground from the sub panel the last hundred feet has hot neutral ground the ground rod at the plug the neutral connected to the Ground Bar in the sub panel but there's nothing else on the system so it runs straight back to the main panel and a zero voltage on it. 30 amps at the main panel 10 gauge wire but I don't need 30 amps I just need 15 or 20 to run some simple stuff like lights I can run the generator for the rest. The way it is now in the sub panel there's a single block with 4:15 amp Breakers in it two for the water pump cuz it's 220 one for the float in the water tank and the other running the RV leg.
 
on the on the long leg of 240 there's only two Hots and a ground from the sub panel the last hundred feet has hot neutral ground the ground rod at the plug the neutral connected to the Ground Bar in the sub panel but there's nothing else on the system so it runs straight back to the main panel and a zero voltage on it. 30 amps at the main panel 10 gauge wire but I don't need 30 amps I just need 15 or 20 to run some simple stuff like lights I can run the generator for the rest. The way it is now in the sub panel there's a single block with 4:15 amp Breakers in it two for the water pump cuz it's 220 one for the float in the water tank and the other running the RV leg.
First off you need to unhook the ground rod at the sub panel. It’s required for the main panel only. As far as having a 30 amp 120vac at least install # 8/3 with ground
 
First off you need to unhook the ground rod at the sub panel. It’s required for the main panel only. As far as having a 30 amp 120vac at least install # 8/3 with ground
I have #8 running the last leg the ground rod is at the receptacle, I had an electrician helping at one point said that needed to be there. So I just need to put in another sub panel with 240 running to it and the 120 leg off that?
 
I have #8 running the last leg the ground rod is at the receptacle, I had an electrician helping at one point said that needed to be there. So I just need to put in another sub panel with 240 running to it and the 120 leg off that?
Yes but please that ground rod is not supposed to be there, all the bonding takes place at the main panel. Any panel sub fed out of that service has to have 4 wires with 2 is your ungrounded wires 1neutral and 1 equipment ground wire. When you start terminating your120vac loads that you need you have to hook your ground wires to the grounding bar and the neutrals have to be separate. You will probably have to buy the ground bar for whatever panel you have. No rod required since you have that equipment ground from your main panel.
 
okay got it okay got it no ground rod. Okay so figuratively draw me a picture. So I have from the main panel two Hots and a ground runs 800 feet. At the end of that I have a subpanel. If I understand correctly you're saying run a second sub panel off of that one. And I need a ground bar in the first one so I can run 4 wires from the second one back to the first one. How am I doing so far?
 
okay got it okay got it no ground rod. Okay so figuratively draw me a picture. So I have from the main panel two Hots and a ground runs 800 feet. At the end of that I have a subpanel. If I understand correctly you're saying run a second sub panel off of that one. And I need a ground bar in the first one so I can run 4 wires from the second one back to the first one. How am I doing so far?
How close did you say the first sub panel is to the loads you want to add. Is it 800 feet and you want a 120vac cable for your other loads ?
 
the first the first sub panel is 800 feet from the main and the loads is only about a hundred feet from the first sub panel
Just run what you need go that panel and since you don’t have an equipment ground use the ground rod at the sub panel. It aches me to tell you use that ground rod but you have to have some kind of ground. There is so many code violations on this application and always pull 4 wires from now on.
 
Just run what you need go that panel and since you don’t have an equipment ground use the ground rod at the sub panel. It aches me to tell you use that ground rod but you have to have some kind of ground. There is so many code violations on this application and always pull 4 wires from now on.
the the setup was installed 15 years ago and whoever did it did not think ahead that's for sure. The ground rod is at the very end at the receptacle and where the equipment is going to be it's not at the panel . that didn't make any sense why the guy said put it there either. Set a reminder the second panel do I just come off the two hot leads coming into the first panel or do I got to run to Breakers over to the second panel to get the power to the second panel? not meant to be pretty just got to get me by until I start building then I'm going to put in a hundred amp panel take a short cut and cut out about 400 ft and do it right.
 
the the setup was installed 15 years ago and whoever did it did not think ahead that's for sure. The ground rod is at the very end at the receptacle and where the equipment is going to be it's not at the panel . that didn't make any sense why the guy said put it there either. Set a reminder the second panel do I just come off the two hot leads coming into the first panel or do I got to run to Breakers over to the second panel to get the power to the second panel? not meant to be pretty just got to get me by until I start building then I'm going to put in a hundred amp panel take a short cut and cut out about 400 ft and do it right.
Glad to hear you are learning and good luck. Be careful you can’t see it or smell it but it can kill. Turn off all power to that sub panel you are fixing to work in.
 

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