RV PARK

[mlacroix]

I am doing a RV park and I am putting in a 400amp 120/240v service to pick up 20 50amp pedestals. According to my calculations, 20 pedestals should be 360 amps so, question #1 is my service size correct?

I am looking to pickup 5 pedestals off a 175 amp breaker. According to my calculations, 5 pedestals should be 130 amps. Question #2 is 175 amp breaker sufficient to carry 5 pedestals?

I am running 4/0 aluminum tri-plex to all pedestals and my concern is with the last pedestal. The last pedestal would be approximately 260 feet from the panel. I am concerned about the voltage drop because of the distance. Questions #3, Should I be concerned about the last pedestal?

I appreciate any feedback and thank you in advance. This is my first RV park, I believe I am complying with the code but the numbers seem low to me.

 

[charlie b]

I agree with your calculations of 360 and 130 amps. I agree that a 400 amp service is the appropriate size. I think a 175 breaker is larger than is needed to serve 5 pedestals, and that a 150 amp breaker would suffice. But you can use a 175 amp breaker if you like, so long as the conductors have an ampacity of 175 or higher. But I do not understand your statement concerning the 4/0 conductors. A 4/0 aluminum conductor has an ampacity of 180 amps. Are you saying that that is what you will run from the 175 amp breaker to a set of 5 pedestals? Is the idea that the 4/0 is a feeder that will connect to each pedestal in daisy-chain fashion, so that the 50 amp breaker on each pedestal serves as the final branch circuit overcurrent device? If so, then that works for me.

Finally, I calculate that a 260 foot run of 4/0 aluminum with a load of 50 amps at 240 volts gives a voltage drop of 1%. I call that a non-problem.

Welcome to the forum.

 

[mlacroix]

RV park---refigured

RV park---refigured

The sites to the RV park have been refigured. Now, where the panel is, I have to run past the first 5 pedestals to reach the next 5 pedestals. When I do the voltage drop calculation do I have to add up all 5 pedestals in the last run, which is 130 amps? To get my voltage drop calculation, does the wire to the first pedestal have to carry the 130 amps? The distance to the first pedestal in the last run is 330 feet.

By my calculation, my 4/0 aluminum tri-plex is only good for 109 amps. So, if I did my voltage drop calculation right, I need to jump wire size to 250 4/0 aluminum urd tri-plex to the first pedestal of the last run and then drop back to my 4/0. Is that accurate?