Distance Allowable on Electric Run Question

[woodlandfarms]

I have two projects for this spring... Hoped to do them myself... But I wanted to make sure I have everything calculated...

I would like to put up an electric gate on our property. that would place it about 700' from the main house. Can 10 Guage hooked to 110 deliver close to that at 15 Amps. I think the gate is rated at 2 amp draw.

Second, the wife want a green house. There is a 220 line running out to an old well head. I was thinking of tying into that and splitting it to give her two 15Amp 110V legs out there. It is around 200' from the house. The line is newer (past few years, yellow jacket, so I think 10 guage).

I checked a couple of websites and it looks like my drop would be only a few volts. Not sure that anything we are using would be affected.

But, for whatever reason, I seem to remember someone telling me you cannot exceed 100' run.

Love some comments on this before I tell the wife it is a go on the projects.

Carl

 

[DieselPower]

You want no more than a 5% voltage drop at the end of your line.

10GA copper wire at 120 Volts AC with a 2 Amp draw would have a 2.47% voltage drop at the end of 700 feet leaving you 117 Volts AC.

The maximum you could run off of the 10GA line would be 4 Amps. 700 feet, 120 Volts AC with a 4 amp draw would have a 4.95% voltage drop at the end of 700 feet leaving you 114 volts.

Not knowing if you might want to do something at the end of the driveway in the distant future you might consider stepping up to 8GA wire. 8GA would be good for a little over 6 Amps at the end of 700 feet and the voltage at the end would be 114 volts which is a 4.66% voltage drop.

Online voltage drop calculator for 120 and 240 Volts AC.

And the NEC voltage drop calculator in Excel file format.

The only problem is I don't think you can run parallel wires at that distance. It's somewhere in the NEC code 301.4.

 

[BB_TX]

For that kind of distance, I think I would consider one of the battery powered gates with solar charger.

 

[Mike120]

I agree with BB, go for battery powered. Although I have 120V circuits out to both of my gates, they only power the trickle chargers to keep the batteries charged. Solar works as well. They are very nice to have during a power outage.

 

[JHFV]

I have a solar powered gate at my house. It has a solar panel about 10" x 10" and it goes into a battery that sits in a panel box on the gate post. Its a marine battery. The gate is a 16' long rod iron gate. very heavy. It works perfect.

 

[woodlandfarms]

I have a solar powered gate at my house. It has a solar panel about 10" x 10" and it goes into a battery that sits in a panel box on the gate post. Its a marine battery. The gate is a 16' long rod iron gate. very heavy. It works perfect.

Was my first thought when I bought the place this summer. In the winter, there is no sun down in the ravine... It would be a Solar Boat Anchor.....

But the trickle charger could be interesting... Maybe unnecessary if I have run the juice all the way there.

Now to cost out 700' of 8 guage...

 

[schmism]

Now to cost out 700' of 8 guage...

stranded wire or NM? if stranded your gonna need twice as much

 

[BB_TX]

You could put the solar panel on top of a pole or at the top of the ravine. The wiring from the solar panel could be small as it would only be carrying milliamps.

 

[woodlandfarms]

So let me add to the question. One of the systems I see is a 24 volt battery with a charger hooked to it. Would my voltage drop be an issue if I was just feeding a step down transformer?

Also, the pole for solar is an idea. I estimate it would need to be 120' high to get some good light... It is a nasty ravine next to hill that blocks all winter sun. We get ice in november, it melts in march even if it 40 out...

 

[firefighter9208]

Woodlandfarms,

Check out the following web site. Mighty Mule Gate Openers They have gate openers that are battery powered and you run a 16ga. multi-stranded dual conductor direct bury wire from your house to the gate. You put the transformer at the house. They say you can run the wire up to 1000'. They get 34 cents a foot for their wire, but I have found 16Ga. multi-stranded dual conductor direct bury landscaping wire at Home Depot for about 12 cents a foot. I am sure that this wire would work the same. You can rent a direct bury trencher at Home Depot for about $80.00 a day to bury the wire.

My gate is about 900 feet from the house, so I haven't yet decided to use the landscaping wire or go with a 5 watt solar panel. Mighty mule has a chart that shows with a 5 watt panel you can open and close the gate 8 times a day.

Chris

 

[Defective]

How about running 240V on that same wire & a 2:1 transformer at the gate? Cut the current (& therefore the line loss) in half. This would give you a total of 16 amps available at 114V with 4.95% loss on a 10 ga. wire.

 

[DieselPower]

Where would he get a single phase of 240 volts? Unless he has 3 phase at his place all he has is two 120 volt leg's in his breaker pannel. Normal house hook up's for 240 volts are two leg's of 120 volts which is more or less 2 phase. If he has 3 phase he would have one leg with a higher voltage but most people don't have 3 phase.

 

[Inspector507]

Where would he get a single phase of 240 volts? Unless he has 3 phase at his place all he has is two 120 volt leg's in his breaker pannel. Normal house hook up's for 240 volts are two leg's of 120 volts which is more or less 2 phase. If he has 3 phase he would have one leg with a higher voltage but most people don't have 3 phase.

I can get single phase 240V out of my panel all day long. Never heard of a residential 2 phase service.

 

[tommu56]

Two Phase is a old industrial power that had 4 wires.
I it was used primarilly in boston, chiacago and philly mostly before 3 phase was out there

Homes have a 220v center tapped ground system 110v from each leg to ground / neutral.

tommu56

 

[Defective]

Yup...

Just run the two hots from the panel (properly breakered of course).

<teaching mode>
Fun fact for the day: Power transmission lines run much higher voltage than needed at the destination. This is why you see those big grey cans on the poles. These are transformers to get 220 volts when they branch off to houses & such. Ohm's law says that current and voltage are inversely proportional.
</teaching mode>

Can you imagine the size of the wires needed to provide sufficient current for a whole neighbourhood if the lines were carrying 220 volts?

 

[SPYDERLK]

I have two projects for this spring... Hoped to do them myself... But I wanted to make sure I have everything calculated...

I would like to put up an electric gate on our property. that would place it about 700' from the main house. Can 10 Guage hooked to 110 deliver close to that at 15 Amps. I think the gate is rated at 2 amp draw.

Second, the wife want a green house. There is a 220 line running out to an old well head. I was thinking of tying into that and splitting it to give her two 15Amp 110V legs out there. It is around 200' from the house. The line is newer (past few years, yellow jacket, so I think 10 guage).

I checked a couple of websites and it looks like my drop would be only a few volts. Not sure that anything we are using would be affected.

But, for whatever reason, I seem to remember someone telling me you cannot exceed 100' run.

Love some comments on this before I tell the wife it is a go on the projects.

Carl

Both should work ok. 15A for a gate is excessive so I assume that is to allow startup surge without flipping the breaker. Voltage to the motor will be a little low, but assuming it starts ok, it will not suffer from the intermitent nature of the usage. The greenhouse is a short enuf run to be quite forgiving in the amt of V sag. All low drains would be fine - lights, fans, motors up to 1/2 horse. - -A microwave ~ probably. Resistance heaters are continuous high drain, but they arent very particular of their power. You just wouldnt get their full rating due wire losses - still useable. In general, Id just be vigilent as to the nature of the power demand on the circuit and its approx balance across the two 110V legs.
Larry

 

[LarryD]

Second, the wife want a green house. There is a 220 line running out to an old well head. I was thinking of tying into that and splitting it to give her two 15Amp 110V legs out there. It is around 200' from the house. The line is newer (past few years, yellow jacket, so I think 10 guage).

Is that cable buired out to the old well head? I haven't seen UF cable with a yellow jacket but I haven't seen everything.

My neighbor had an issue with an outdoor light that was plugged into a GFCI outlet. The outlet kept tripping. When we looked at the wire, it was indoor Romex direct buried and I think the jacket was letting moisture in, just my opinion. After we changed the cable to UF, no more problems. If you're gonna put outlets in a green house, they should be GFCI. Now if the supply side has an issue I don't know how the GFCI will react...I'll have to think on that one.