Wire gauge for a 200 ft run on 30 amps or 50 amps?

[map40]

Anybody has a good calculator for wire gauge? I need to do a wire run of 200ft buried wire. I can do 50amps or 30amps. Any advise will be greatly appreciated!

[time2roll]

SAR Tracker wrote:
wire size calculator (dot) net

If you use 200', 240v, 35 amps, 3% in the calculator you only need #6 wire. This still allows two large draw items on each side of the panel and plenty of ampacity if you draw close to 50 amps for a few minutes.

[Matt_Colie]

Sorry guys,

I just read the whole thread and I can't sit back any longer.

First: If you don't buy enough copper to do the job right, you may save money now and you will probably pay for it forever......

Second: A 3% voltage drop is meaningless. Voltage drop is Volts Lost and irrespective of the starting terminal voltage. Most of these tables give you that 3% number and don't mention that this is only one way. There has to be a return.

Your current coach is 30A? It is a waste of time to set up for 30. Put in wire for 50. Use 3 conductors but you can save on the neutral and size it for 30 (unless you are firing a Sigma Arc) because when you load the 50, some of the load will be going out the other 50.

Don't bother running a ground unless your local inspector requires it.
Bury a new ground rod at the new service box.

Bury two plastic conduits. Put the service power in one and use to other for communications, like Cat6 or TV coax or ?? (Who know what is next - fiber maybe?) Do Not Use 90s. Split the turn between two 45s.

Think about burying a water line out there too.

Digging is cheap, unless you have to dig it up to do it again.

Do I have to add BTDT????

Matt

[Cummins12V98]

enblethen wrote:
You can use a different insulation on the wire that is less expensive if it goes in conduit as compared to USE type direct burial wire was my point.

Still needs to be rated for potential water that can get into conduit.

I thought I was being smart bu pulling romex thru 3/4” pvc that was well glued. After a couple years the hot went to ground.

[enblethen]

You can use a different insulation on the wire that is less expensive if it goes in conduit as compared to USE type direct burial wire was my point.

[map40]

Old-Biscuit wrote:
🙂

enblethen wrote:
3% for voltage drop.
Hopefully, Old Biscuit is indicating copper wire and not aluminum.
Direct burial or are you going to put in conduit?

:S

I was going to have the GHana Dancing Pallbearers to do the burial 🙂

[Old-Biscuit]

🙂

enblethen wrote:
3% for voltage drop.
Hopefully, Old Biscuit is indicating copper wire and not aluminum.
Direct burial or are you going to put in conduit?

:S

[garym114]

Use the calculator at the bottom of this page. It gives you the voltage drop.
https://www.powerstream.com/Wire_Size.htm

[MEXICOWANDERER]

A pair of 600 volt transformers Major reduction in wire cost.

[ktmrfs]

naturist wrote:
I'll second what @Old-Biscuit said. Don't scrimp on wire. As wire is expensive in those sizes, it is none the less the cheapest part of the whole deal, when you consider also the just the hassle of blown fuses/breakers, brown-out damaged gear, etc.

x2. the other consideration for going for a 3% drop is the implications of any inductive load such as an AC motor, like your air conditioner. starting current for that could be 50-70A or so momentarily. with to small a wire size, voltage drop can be large enough to turn that momentary draw into many seconds, or even having the motor stall and not start due to voltage drop and if your lucky only pop the breaker.

[Gdetrailer]

Old-Biscuit wrote:
3% Max Voltage drop for that 200' run

Otherwise you will have Low Voltage any time the supply voltage drops below 115V


50A #1AWG
30A #3AWG

Do NOT scrimp on the wire size...........

Agree with not scrimping on the wire but might get sticker shock when you get the prices for this..

#1 AWG copper single strand is going for around $1.90 per ft

For 50A 240/120 you will need 3 runs of #1 (two HOT and 1 Neutral) and 1 run of #3 (for ground)..

I suspect by the time you buy wire, conduit and other needed materials you will be north of $2,500 and if not doing the work trenching and installing conduit that labor cost could easily get you well above $3500..

I would suggest, finding a closer spot nearer to your electrical source that could knock off 100 ft of wire which would get your cost a bit more reasonable..

Alternately, nothing says you HAVE to breaker it for 50A, you could run 240/120 but use a lower amperage breaker like a 30A double instead of 50A double. That would allow you to use lighter ga wire..

[ssthrd]

map40 wrote:

Lynnmor wrote:

2oldman wrote:
advice.

Thank you for that, I cringe whenever I see this and it reminds me of the state of education in America.

No, no, don't go blaming the state of education in America. Here is the problem: I speak 6 languages and use them frequently, so my phone and computer do not know what I am writing and the autocorrect wants to commit suicide every time I chat with somebody different. You should see it when I go from Spanish to Cantonese...

That would be horrible...........

Old story about a Ferrari owner who had a mechanical problem, and couldn't decide whether he should consult a mechanic who just graduated from Ferrari School, or the old guy down the street who was "uneducated" but has been working on Ferraris for 30 years. Hmmmmmm....... Wonder what he did.

Sorry to get sidetracked. Couldn't resist.

[map40]

Lynnmor wrote:

2oldman wrote:
advice.

Thank you for that, I cringe whenever I see this and it reminds me of the state of education in America.

No, no, don't go blaming the state of education in America. Here is the problem: I speak 6 languages and use them frequently, so my phone and computer do not know what I am writing and the autocorrect wants to commit suicide every time I chat with somebody different. You should see it when I go from Spanish to Cantonese...

[valhalla360]

Google voltage drop calculator.

[time2roll]

Yes 3% although for a dedicated RV you can probably size it for 35 to 40 amps but not less than #6.
Definitely go 4 wire 120/240 circuit.