Trickle charge feasible?

[Bluedog225]

I’ve got my Quattro and my SOK rack batteries just about set up. And I’m having a waterline put in from the road. About 1000 feet.

The guy put in the waterline in does odd jobs in his spare time to pay for his bobcat. His real job is electrician.

He suggested putting an underground feeder to my cabin. It’s about 800 feet from the existing pole and meter loop. Running line overhead is prohibitively expensive and they want a 30 foot clearing on either side of the line which is not going to happen.

I’m pretty sure a standard 240 V 100 amp service wire is going to break the bank. But I wanted to ask if there’s any smaller, cheaper line that could provide 24/7 slow charging to my rack, batteries and some supplemental juice for whatever.

Is there an obvious answer that makes sense? It can involve higher voltage and transformers as my stuff is housed in a conex and I don’t think the noise would be a problem. Though the cost of transformers might be.

Or something clever taking into account the voltage drop from the pole?

Thanks

 

[kayakingphotos]

How many kWh/day do you think you'll be using? And how much of that can you generate from solar vs having to feed it the 800 feet from the grid?

My thought on the subject if you absolutely need to have a way to charge from the grid would be to install an EG4 Chargeverter. Figure out how many kWh/day you need to charge and then size the wire for the 3% AC loss.

Let's say you need 10 kWh/day. That would be a constant draw of 415 watts. For efficiency loss, round that up to 500 watts. That results in a 2.1 amp draw at 240 volts AC. That at 800 feet using 12 AWG wire actually gives you a voltage drop of 2.4%.

Personally I would go with bigger wire than that to future proof it, but that is based on budget. Definitely install big enough conduit to be able to install larger conductors in the future....

Patrick

 

[Quattrohead]

I think 10awg uf is the least expensive cable you can buy for the amperage.
Run that and then see what voltage is being dropped under load, do some calcs and decide if you want to breaker it at 15/20/30 amps.

 

[webbbn]

I think 10awg uf is the least expensive cable you can buy for the amperage.
Run that and then see what voltage is being dropped under load, do some calcs and decide if you want to breaker it at 15/20/30 amps.

I don't know all the details of underground wiring, but it looks to me like copper 10 awg UF is about the same price as 2 awg aluminum.

 

[Bluedog225]

I could be pretty comfortable with 4000 watts. To run a mini split or two and some lighting.

Supplemented by solar arrays.

20a at 240v with 2-2-2-4 mobile home feeder at 800 feet. Would seem like luxury. And maybe affordable.

I’m way over my head though in terms of this. I appreciate the input.

 

[Bluedog225]

Of course, my quattro doesn’t accept 240. Darn it. Will need a step down.

 

[Bluedog225]

Merry Christmas everyone!

If I have to feed the Quattro with 120, and I think I need to run the line at 240, does it make sense to run 240 only? Then transform it down for the Quattro to service my 120 loads. And that would let me run air con on 240.

I’m thinking that only requires 3 wires. Is that right?

Thanks

 

[400bird]

The grid provides 2 hots and a neutral. You add the ground on site.
I'd advise against running 120 only to the place. You're already in the trench, I'd be pretty upset myself if the situation changed later and I wanted split phase.
Run the wiring for split phase even if you only hook up to one leg.

 

[Bluedog225]

Agreed on the 240. It sounds like 3 wires at 240 and the highest ampacity I can afford.

Along with one of these. 32 amps at 240 volt. It may be worth doing.

 

[Rocketman]

The 2-2-2-4 UF would be good. But you don’t need the #4 (that’s ground - you supply ground locally). See what other options you have maybe a 2-2-2 or 1-1-1.

 

[400bird]

Oh, I should add that my comment above is assuming the meter/disconnect will be at the load end, not at the utility pole. If the utility makes the drop at the pole and requires a disconnect there, you would need a ground wire in the trench.

 

[Bluedog225]

That’s too bad. The meter will be set the pole.

 

[time2roll]

As long as there is a battery at the cabin I would go 240v and use a separate charger like a MeanWell to keep the battery topped up only.
Will not need so much power if it runs 24/7 keeping the battery topped up.

 

[400bird]

That’s too bad. The meter will be set the pole.

The neutral/ground bond needs to be at the point of first disconnect. I think you'll be forced to put that at the meter, which means you've got to have a separate ground and neutral from that point towards the house.

 

[timselectric]

Agreed on the 240. It sounds like 3 wires at 240 and the highest ampacity I can afford.

Along with one of these. 32 amps at 240 volt. It may be worth doing.

View attachment 185030

This would be a waste of money.
An autotransformers neutral must be connected to the existing neutral if it's fed by a split-phase service.
So, you have to run the neutral, either way.
I'm not sure how much that autotransformer costs. But it's probably cheaper to get a Chargeverter.

 

[400bird]

What's the point of the auto transformer in this set up? Is it just trying to save cost and run one less conductor (neutral) in the trench?

 

[timselectric]

What's the point of the auto transformer in this set up? Is it just trying to save cost and run one less conductor (neutral) in the trench?

I believe so. But it doesn't work that way. You still have to run the neutral.
So, it's pointless. Cheaper to just run the 4 conductors. And use whatever you want from them.

 

[Bluedog225]

Ok. Got it. This is what I’m trying to figure out. Thanks for the input.