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optimistic
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# Posted: 26 Feb 2022 07:10am
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Hey all,
I asked this before here. I am planning running a wire for my cabin from a neighbor who is about 1300-1500ft away. My tiny 144sqft cabin uses very little power and I run it on my Honda so a 15amp or 20amp breaker on his side is enough.
When using those online calculators with voltage drop it shows 3/0 aluminum wire. I called a local store there about buying such wire and the guy asked me why I need such a massive wire and when I told him he was like - you can do a 10awg. Very very different than a 3/0.
So which is it?
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optimistic
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# Posted: 26 Feb 2022 07:19am
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Sorry not 1500ft... 800-1000ft
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Brettny
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# Posted: 26 Feb 2022 07:19am
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The calculator dosnt lie.
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ICC
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# Posted: 26 Feb 2022 08:53am
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Science vs an uneducated opinion
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ICC
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# Posted: 26 Feb 2022 09:02am - Edited by: ICC
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If all you ever ran were a few LED's or other small amperage loads 10 AWG could be used.
2 amps through 10 AWG copper = 3.2% voltage drop for example. That is OK. 5 amps, though, drops 8% with the voltage dropping to 110 from 120. Not too good for some devices. And for any loads larger than that the larger wire is needed. So you could use 10 AWG and also keep the generator for big loads. Some people do that with their solar system with a small 300-watt inverter and start the genny for other stuff. Personally, that is too much bother for long term use.
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gcrank1
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# Posted: 26 Feb 2022 10:41am
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For 1000' @ 15a
Copper awg 1/0
Alum awg 3/0
@ 10a
Copper awg 2ga
Alum awg 1/0
@ 5a
Copper awg 4ga
Alum awg 3ga
You do not want to be trenching by hand nor do you want a 120vac wire laying on the surface or hung in trees. This means alum awg URG for direct burial.
Can you get 2 cond alum URG 1000' for $2/ft? If so thats $2000 plus renting or hiring the trencher. And the other expense of the small service panel/conduit from ground at both ends/misc. Im seeing $3k real quick.
Alum wire will have special install considerations at the termination because of corrosion mitigation.
The work to put in thin wire is as hard as for thicker.
Do you want to do the work and expense for an uncertain 'supply relationship' in the future?
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gcrank1
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# Posted: 26 Feb 2022 11:06am
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Can you link your orig inquiry on this thread so we dont have to search for it; the continuity (nice elec term that) is lost.
I understand that if you just had 'flip a switch' ac these questions wouldnt matter, but in looking for cost effective options for you I think they are important.
Is this a part time place?
How many days at a time do you tend to be there or want to plan for?
If you break down 24hrs into 4-6hr segments can you track/report your amps/watts usage to get a meaningful understanding of your use?
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paulz
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# Posted: 26 Feb 2022 01:11pm
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What about getting one of those power box dealies with the battery and inverter. You could have it on small gauge wire to your neighbors to keep it charged, and use it for times of heavier amperage needs.
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optimistic
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# Posted: 26 Feb 2022 01:36pm
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Hey everyone, sorry for the lack of continuity. It is a fine word. And we do have a lot of uneducated opinions vs science nowadays. That's what it thought when the guy said that. Good thing he owns a electric supply store.
I've researched solar to death. Looks like a 3-4k advanture with risk of making mistakes and killing the expensive part of it (batteris) so solar isn't an easy route for me. I know that some can go solar for less but it really is based on needs and based on mine that is the cost... Believe me.
I agree that this guy can change his mind one day but... He doesn't live there. It's a rental of his so he isn't even there. Hoping it'll be something we set set and forget.
As to cost... I found a 1000ft coil of 3/0 aluminum direct burial for $1100. Renting a large trencher from hd for two days will cost me zero (long story why) then my electrician says that I can buy a fuse or phase box (briefly discussed on the phone so I might have misheard) that has large lugs that can accept the wire. Then from there I feed the cabin with a 10awg for the last 3ft. So not too bad.
Cost of that box can't be more than $100.
So a lot less expensive than solar for me plus much more convenient and could allow for things that solar can't allow... This guy just bought so probably won't sell anytime soon and again. For this cost it is worth a shot I think.
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gcrank1
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# Posted: 26 Feb 2022 04:16pm - Edited by: gcrank1
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Im not an electrician or up on 'da code', but you might want to consider running from his service box to an auxillary(?) cb box where you can access it; ie, not be locked up in his place.
There may be times you want to disconnect 'at the source'.
From your number crunching and my limited experience it sounds as if your proposed wire run for 'real ac power' may be about the same as a low-powered solar set up. In fact, that roll of wire is comparable to my 2 new 100ah LFP bats alone, but I have all the rest of the solar stuff, Im just upgrading my storage. My rough figuring is that to have somewhat the same solar system (sans bat cost) would be $2000-2500 today and I still have to run the inv/gen for 'big stuff'.
Amortizing costs out over 10yrs means a $2400 up-front cost for 'whatever your total system is' comes to $20/mo. That is worth it to me to be off grid, no ever rising bills and still have power when the grid is down.
If I did go grid here my current mo bill would be about $30-35 with very little of that actually being power used. Over 10yrs that would be min. $3600 so basically my self sufficient system/ Not Having to pay that grid-tie fee every month is 'paying me back' over time.
I pitch that out so you have an idea how to calc what a fair amount to give your neighbor is for the tie-in.
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optimistic
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# Posted: 26 Feb 2022 05:40pm
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Yeah I will discuss monthly payment with him as well. He said he lived off grid in Cali for 3 years and understand the benefit of electric power.
I believe that what you said is what my electrician said. Having a box with disconnect at my cabin coming from him so I can shut of the power from him. Then that box will feed my cb box in my cabin.
Thinking about this one: https://www.homedepot.com/p/rental/Barreto-Manufacturing-Inc-Hydraulic-Trencher-18-E7 12MTH/309005753
I dug on my land after a few days of rain vs after a dry spell. Massive difference. So much easier to do when it is wet so I will try to shoot for that.
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ICC
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# Posted: 26 Feb 2022 08:56pm
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Quoting: optimistic Having a box with disconnect at my cabin coming from him so I can shut of the power from him. Then that box will feed my cb box in my cabin.
ALSO, a box or small service panel with a disconnect of some kind at the other end so you can make the whole line dead if that need ever arises without needing to have access to the breaker panel at the other end.
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gcrank1
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# Posted: 26 Feb 2022 10:34pm - Edited by: gcrank1
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Yes, Id want a lockable box accessible at all times at the source end (dont want somebody playing around and shutting your box down).
Line run to cabin right to the service box.
This way you have 'your grid' sections able to be isolated for whatever reason.
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Shadyacres
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# Posted: 27 Feb 2022 09:15am
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I think if it was me in same situation, I would think really hard on the solar route. Unfortunately, where I'm at (base of mountain with lots of trees, I would have trouble getting enough sun. Power supply is only going to continue to rise, and you have no guarantee how long your neighbor will rent etc.
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gcrank1
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# Posted: 27 Feb 2022 03:48pm - Edited by: gcrank1
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The economics of it are a double edged sword to me.
The grid tie is Real Power, at a never ending price tho spread over time.
The place will look like it does now.
That same amount of money will buy components for a small scale solar, then you are the Power Company.
The power will not be as much as grid except for when you run the gen. Conservation will be your friend though you will love the quiet from not having to run the gen whenever you want power. It will maybe be not dissimilar to your current lifestyle there.
The solar array will be a visual intrusion unless it is on the roof (I generally prefer ground mount for the practical aspects). Imo the 'look' of an array is a detraction from the site if it is not incorporated into the building(s); ie, on roof or beside a south facing wall, etc. My wife and I both dislike the 6xpanel array out in the sun 100' away. We like the power and independence from the grid. If I planted a row of evergreens between the cabin/deck and array in 15yrs it would be hidden. We wont likey be cabin'ing in 15.
But did I tell you we like the power and independence from the grid.....
Decisions, decisions
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Irrigation Guy
Member
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# Posted: 27 Feb 2022 05:50pm
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Will you have a sub panel at your place or will this be a single circuit?
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neb
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# Posted: 28 Feb 2022 10:13am - Edited by: neb
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Your service scenario is right on the edge with distance and what you want to do.
For example, the nominal residential voltage is ~120 volts, although the voltage may actually
range from 114 volts to 126 volts.
I would check/measure voltage at your starting point and go from there.
I also will add that a breaker box with disconnect will need to be at the entrance of power going into a structure. so, two should be used one at the take off and one at your cabin. That is one thing some have talked about in above posts. That is a code thing you should follow what your electric code requires. A safety issue that you want to do for your safety.
Your voltage drop should never drop under ~116V. So, voltage at where you want to tie in at will dictate
your wire size.
If you use 1/0 aluminum for 1000 feet with a 15-amp load would see ~6 volt, drop.
So, at the measurement you get at where you want to take power from, and the voltage is 124 volts and you have a 6 volt drop. That would be ~118 volts with a 15-amp load.
So, less voltage at the take-off/source will have a huge effect with the results you want at the end of that 1000 feet run.
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gcrank1
Member
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# Posted: 28 Feb 2022 10:51am
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Waayyy great info Neb! 
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optimistic
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# Posted: 27 Mar 2022 07:48pm
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Great info. Sorry for being away. Too much work...
So if I understand neb correctly - I should test the voltage he has to determine if 1/0 will work?
And yes my electrician told me I'll need a fuse/disconnect box on my end that will be outside and taje the 1/0. Then from there I'll feed my panel indoors.
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Bruces
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# Posted: 28 Mar 2022 08:28am
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Why not go with a 220v feed .
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Nobadays
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# Posted: 28 Mar 2022 09:18am
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Quoting: Bruces Why not go with a 220v feed .
Exactly.... even if you need to buy a duplex breaker to clear a space in the neighbor's panel. Half the line loss.
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paulz
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# Posted: 28 Mar 2022 09:59am
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Quoting: Nobadays Exactly.... even if you need to buy a duplex breaker to clear a space in the neighbor's panel. Half the line loss.
You sure? It's two 110s right?
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Nobadays
Member
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# Posted: 28 Mar 2022 04:18pm
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Using 1,000' - 120vac/24vac - @ 15amp - 1/0 aluminum wire
120vac, 6 volt OR 5% drop, 114vac at destination
240vac, 6 volt OR 2.5% drop, 234vac at destination
The voltage drop stays the same but the percentage of loss is cut in half. According to this calculator: HERE
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paulz
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# Posted: 28 Mar 2022 04:33pm
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But you need 3 lengths of wire instead of 2, right? And you need all 240v appliances?
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Nobadays
Member
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# Posted: 28 Mar 2022 05:42pm
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Yeah I think you do need 3 wires, 2 hots and the neutral, don't think you would have to pull the ground from the supply but not sure about that. Someone smarter than me can probably answer that..... No he would not need 240v appliances, just feed both sides of the load center as in a normal application.
Care would need to be taken to NOT USE 240v or high amp/wattage appliances/devices as even a 20amp draw will exceed the 3% acceptable line loss. So..... maybe just bringing 120v makes more sense. It just seems like, a lot of expense for little gain. A couple of light bulbs and a phone charger.
A pretty simple/inexpensive solar setup would accomplish the same thing with less ongoing costs. But then... does he have a good solar site? Maybe solar won't work.
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paulz
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# Posted: 29 Mar 2022 09:55am
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Quoting: Nobadays No he would not need 240v appliances, just feed both sides of the load center as in a normal application.
But then if you run a 120 appliance you only use one side, therefore the higher drop, right?
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Nobadays
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# Posted: 29 Mar 2022 12:21pm
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Good question! You would be bringing 240 into the load center but each hot leg feeds a side of the box.... so unless it's a 240v draw in essence you are just drawing off one leg. I think?
Hmmmm... ICC?
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gcrank1
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# Posted: 29 Mar 2022 01:12pm
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I'll take a shot!
Delivered 240 to the cabin box will have x line loss.
Whatever is taken off that box, which is now the source, will only have its line loss from box to appliance.
Or not?
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Brettny
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# Posted: 29 Mar 2022 02:38pm
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Quoting: Nobadays Good question! You would be bringing 240 into the load center but each hot leg feeds a side of the box.... so unless it's a 240v draw in essence you are just drawing off one leg. I think?
I dont think that's how it works. 120v load means you need to run the calculator for 120v. Either way it's going to be double the 240v drop. Ohms law comes in here. 120v at 10a would be 240v at 5a.
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paulz
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# Posted: 29 Mar 2022 02:38pm
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Quoting: Nobadays You would be bringing 240 into the load center but each hot leg feeds a side of the box.... so unless it's a 240v draw in essence you are just drawing off one leg. I think?
That's how I see it. But, with two legs he could run the fridge or whatever on one and lights etc. on the other to reduce the loss.
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