power over one wire

[Menticol]

Don't exagerate, Thunderchild. Beign offensive online is great sometimes, but the op doesn't deserve that. At least he took the time to ask what to do, and for me this is a very smart act. Also note he's only trying to power a small wooden house, its a very innocent thing.

(offtopic) Compared with, For example, the scandals about some contractors who build homes for poor people here in Bogotá, "engineers" who break all the construction codes and common sense, use the worst materials, in dangerous terrains, and ugly designs... that is not only mad, is criminal! They deserve your commentaries


for the OP: I know it's more expensive, but is the correct way for your safety: Use two wires, and remember adding a circuit breaker at the beginning of the wire at your home, and another in the destination house. Send both wires through a PVC pipe, to prevent humidity or garden tools to reach them

 

[Thunderchild]

what ever its a crazy idea its just so obvious thats its not a good idea, I just can't beleive its being considered

 

[PhillDubya]

what ever its a crazy idea its just so obvious thats its not a good idea, I just can't beleive its being considered

I have to agree. This is ludicrous, to even contemplate something like this involving children, just to save a little bit of money for one whole extra 250 yard wire.

As far as the theory behind it... How are you going to carry the same current in the ground, that you carry through the wire, at a relatively low voltage, for 250 yards?

Most of the methods, from what I understand in Single Wire transmission, involve either transmission level voltages, or really high frequencies. Assuming he does have enough sense not to use transmission level voltages around his children, and he opts for some type of high frequency system, how is he going to pay for a system to generate and maintain high frequencies, when he can't afford a single 750 ft wire?.... Back to square one.

The solar panel is a good idea, but how is he going to afford that, if he cant afford a 750 ft wire?

Solution? Tell the guy to work some over-time, and buy another wire.

 

[blueroomelectronics]

Solution? Tell the guy to work some over-time, and buy another wire.

That's the real answer. Hope he can cough up the change to put a breaker on it.

On second thought don't do it. Treehouse's and electricity don't mix.

 

[audioguru]

I thought that electrical wiring has three wires, not just one or two.
Maybe the outdoors electrical cable should be powered through a ground-fault interrupter.

 

[Thunderchild]

quite true i think no one has hardly mentioned an earth wire and relative circuit breakers as its as it is a mamoth task just to get this guy to think of the barest essentials: 2 wires versus 1

 

[Hero999]

Single-wire earth return - Wikipedia, the free encyclopedia

I'll have to run some experiments with a 50' extension cord, using 120 vac, possibly through an isolation xformer. With 25Ω earth resistance I should be able to substantially light a small bulb. Driving a ground rod at the receiving end is probably the hard part. Deeper rod = brighter bulb?

Never tried it.

What's the insulation on this cable rated to?

Increasing the voltage is the answer, 120V is far too low.

You could use a microwave oven transformer at either end to reduce the current and therefore power losses.

Seriously, 400W at 120V is only 3.33A so 0.5mm² (20AWG) twin core cable is fine and is very cheap.

As this is outdoors you'll also need to protect the cable from the lawnmower which is the expensive part.

 

[Willbe]

What's the insulation on this cable rated to?

Increasing the voltage is the answer, 120V is far too low.

You could use a microwave oven transformer at either end to reduce the current and therefore power losses.

Seriously, 400W at 120V is only 3.33A so 0.5mm² (20AWG) twin core cable is fine and is very cheap.

As this is outdoors you'll also need to protect the cable from the lawnmower which is the expensive part.

It's all in the planning stage; if he posts back I'll update you guys.

 

[GonzoEngineer]

But it seems to me they used to send telegraph signals with only one wire.

Two wires actually.....one was up on a pole, and the other was the metal rail of the track.

Maybe he could run a railroad track out to the tree house!

 

[Willbe]

Maybe he could run a railroad track out to the tree house!

He'll need one if he carts 200# of batteries out there every so often.

 

[Thunderchild]

actually what he proposes doing will probably violate his electric boards regs. if you use the ground as neutral (well he could try using it as live but there would probably be an almighty bang) your essentially using what should be earth as neutral and by doing this and if memory serves this can bypass metering so your not paying for the electricity. of course if you have an RCD in the house its likely that it will keep cutting out as again neutral has been replaced by earth so its not going through the RCD, infact you theoretically wouldn't need to feed the neutral into the ground as its already there as the earth. I bet he's confused now.... yea see its not a good idea

 

[jpanhalt]

Sorry to jump in late. I did glance over the previous posts. In the US, we have what might be called a one-wire system. Our white conductor is grounded at the service entrance. There is no reason other than code that it can't be grounded elsewhere. Thus, the one wire is black for 110V AC.

I built a commercial shop 25 years ago and the electric company ran only two service wires to it for 220 V single phase. We drove a grounding rod and thus had two, 110 V circuits, i.e., one wire for each. Everything was to code.

The OP's idea doesn't sound as crazy to me as some of the other posts make it out to be.

John

 

[Thunderchild]

if the neutral in america is also the earth - not a bad idea - just have to hope people don't get them swaped, then it would theoretically work and not be cheating the electric board out of electricity but still to actually carry power through the ground is not a good idea, basically you don't have 1 wire power supply in america you have a neutral and live like you do in the UK (and the rest of the world) but instead of a seperate earth wire the neutral is earthed, this is the same in england but the neutral is earthed at the substation not in the building. the only issue with no seperate earth is that you could potentially make appliance casings live if plugs are wired the wrong way round or at least thats how it would work in the uk if we didn't have a seperate earth. neutral essentialy is earth as well but as a safety precation a seperate wire is used to earth applice casings. of course one can argue this new fangled system thats very clever at risking a frying: double insulation yea a good joke, my hedge trimmer is "double insulated" but that was not much help when I went through the live part of the cable as the blade was "insulated from internal electrics" whilst I accidentally cut through the live cable my trimmer blade actually became live ! if it was earthed the good old fashioned way the power would have blown ! and everything stopped preventing me from frying myself and alerting me to a very serious problem, I only realized the cable was cut 1 month later (today), there are still houses in the UK that don't have RCD's fitted mine being one

 

[Thunderchild]

the electric company ran only two service wires to it for 220 V single phase. We drove a grounding rod and thus had two, 110 V circuits, i.e., one wire for each. Everything was to code.



John

thats odd so basically your saying that the power was delivered by a 220 V transformer with an earth center tap ! but power is generally carried in 3 phase so you would have the options of 110 V and 180 ish volts sounds odd unless rather than carry 3 phase 110 the power is carried as two 110 volt lines that are 180 degrees out of phase with each other but then 1 wire would power one building and the other another and you would hope that both used about the same or you woud be loosing on efficienzy

 

[arunb]

It should be possible to use a single wire for a single phase supply.

But there might be a problem, if phase and neutral were to be interchanged..

 

[Thunderchild]

It should be possible to use a single wire for a single phase supply.

But there might be a problem, if phase and neutral were to be interchanged..

precisely one big bang

 

[jpanhalt]

thats odd so basically your saying that the power was delivered by a 220 V transformer with an earth center tap ! but power is generally carried in 3 phase ...

Not where that building was built. It was over half a mile to the nearest 3 phase.

As for the comments regarding doing it backward, anything can be messed up. Nothing is fool proof.

Nevertheless, the point I was making is that in the US, dual, one-wire systems are common, meet code, and work well.

John

 

[Thunderchild]

but can you guarantee the ground to carry the current ? thats why is would be sensible to use 2 solid wires you can't carry KW through the ground, you can use neutral as earth but then people need to wire their plugs right

 

[jpanhalt]

You most certainly can carry KW of power. My heavy stuff ran on 220 (both wires), but I ran 20A at 110 for a few things. John

 

[audioguru]

Homes in North America use single-phase 230V center-tapped. The center-tap is connected to neutral and is connected to earth at the entrance. Most receptacles are 115V but dual receptacles in the kitchen have one outlet using one-half of the 230V and the adjacent outlet uses the other half of the 230V so that each has its own 15A breaker that are joined together. Heavy duty electrical things use the entire 230V then there is no current in the neutral wire which might be the ground to John's shed

EDIT: words in bold.