About to spend a lot of money tomorrow on this system (am I making a mistake?)

sunshine_eggo

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Well nobody trashed the Victron dealer who told me the AutoTransformer (placed in Location A) would solve the problem of powering the GSHP and providing 120V to the cabin. So it seems that this should work.




Thank you fellas for digging into that. @Hedges do you agree the most that GSHP will demand is 4600W which is no issue for the Multiplus supplying 8KW?

He will once he sees RLA and LRA are the same. :)
 

AlaskanNoob

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He will once he sees RLA and LRA are the same. :)
I tried to confuse him by giving him a long PDF with lots of charts and then not telling him which model number I was using.

I personally get confused beyond watts = volts x amps. I'm pretty proud of myself for learning that but anything beyond that confuses me.

I'm sure you folks do a lot of facepalming from my posts since I'm way over my head. Now just imagine that I'll be doing the trenching with an excavator and digging the horizontal loop and I also don't know what I'm doing with an excavator. I'll no doubt have to cut some trees down while I do that, and I barely know how to use a chainsaw. It's a real party up in my neck of the deep dark woods...
 
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AlaskanNoob

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One tiny little hitch....but a good one (for me). I just got a solid quote for BlueNova 48V 100AH batteries that would save me a bunch of money and possibly avoid a 10 week delay getting the batteries. They are compatible with Victron too.

Anybody know anything about these batteries? A search on this forum didn't return much and Will hasn't made a video on them that I've found. Nor are there many recent videos about them on YouTube.
 

AlaskanNoob

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I found this discussion of them. Can't seem to find the specs for that battery though so I'm not sure what max charging current is.


And a better discussion here.


I think I'll stick with the Pylontech order since this project is pretty important to get right. Plus I don't want to hose the guy on this forum that is selling them to me.
 
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sunshine_eggo

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After the AutoTransformer does what it does it's still going to send 230V down that long 500 foot wire right? So for wire sizing nothing should change?

No. You'll need to run 4 wires now. L1, L2, N and G. It probably comes down to the following:

Is it cheaper to run 4 wires to each cabin, or is it cheaper to run 2 wires to each cabin and have an autotransformer at each cabin? I would ask your dealer about that.
 

AlaskanNoob

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No. You'll need to run 4 wires now. L1, L2, N and G. It probably comes down to the following:

Is it cheaper to run 4 wires to each cabin, or is it cheaper to run 2 wires to each cabin and have an autotransformer at each cabin? I would ask your dealer about that.
He's telling me the AT will be right next to the Multiplus. Which will be 500 feet away from the cabin. Haven't talked to him about the wiring though.
 

sunshine_eggo

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He's telling me the AT will be right next to the Multiplus. Which will be 500 feet away from the cabin. Haven't talked to him about the wiring though.

Note that while we've been talking 230VAC, the MP is adjustable to 240VAC, and I would recommend that.

Right. The AT is what gives you the 120/240VAC split phase from the MP 240VAC single phase thus requiring you to run L1, L2, N and G to each cabin. L1, L2 and N need to be the beefy boys, but G can be 8awg.

Actually, even with the the AT at each cabin, you'll still need to run L, N and G from the MP to each cabin AT, but the G can be 8awg as in the other scenario.

BTW, what is location A?
 

AlaskanNoob

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Note that while we've been talking 230VAC, the MP is adjustable to 240VAC, and I would recommend that.

Right. The AT is what gives you the 120/240VAC split phase from the MP 240VAC single phase thus requiring you to run L1, L2, N and G to each cabin. L1, L2 and N need to be the beefy boys, but G can be 8awg.

Actually, even with the the AT at each cabin, you'll still need to run L, N and G from the MP to each cabin AT, but the G can be 8awg as in the other scenario.

BTW, what is location A?
So I was planning on running 230V with a 1 AWG or 1/0 wire. Now that it's going to be split up, can I assume those wires will be smaller? I'm not going to have to run 3 x 1 AWG wires will I to cover the 500 feet along with the 8AWG?

Location A is where the PV, inverter, SCCs, and AT will be located. It's the only sunny spot on our property but it's 500 feet from our cabin.

When you say auto transformer at each cabin....I'm planning on keeping that component at Location A with all the other solar equipment. I don't need another autotransformer at the structures I run the wires to right?
 

sunshine_eggo

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So I was planning on running 230V with a 1 AWG or 1/0 wire. Now that it's going to be split up, can I assume those wires will be smaller?

No.

I'm not going to have to run 3 x 1 AWG wires will I to cover the 500 feet along with the 8AWG?

You will need the previously calculated 3 thick wires (instead of the 2) and an 8AWG ground.

Location A is where the PV, inverter, SCCs, and AT will be located. It's the only sunny spot on our property but it's 500 feet from our cabin.

Is there already a structure at location A?

How far is B from C?
 

Hedges

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Well nobody trashed the Victron dealer who told me the AutoTransformer (placed in Location A) would solve the problem of powering the GSHP and providing 120V to the cabin. So it seems that this should work.




Thank you fellas for digging into that. @Hedges do you agree the most that GSHP will demand is 4600W which is no issue for the Multiplus supplying 8KW?

I sure appreciate you guys keeping me out of trouble by providing your generous expertise and making this forum a goldmine for dummmies like me.

Total unit FLA 25.3A x 230V = 5819 VA

So you at least need that.
"Fan motor FLA 3.9A", let's assume 19.5A starting surge, 15.6 A more than running. 3588W more.
If you're lucky, fan is started up first while compressor isn't running.
But at least plan on 9.4kW surge. I think you should have a bit of extra power available, and obviously I can't guarantee we've interpreted the data sheet correctly and conservatively.

I find no mention of "PF" or "Power Factor".
I would like inverter drives to present a simulated resistive load (PF = 1.0, current drawn is a perfect sine wave), but some just swallow little gulps of current off the peak of voltage sine wave.
Such loads could present a larger demand on your inverter.
Maybe ask vendor of GSHP about what size generator and inverter are needed to run it.
 

AlaskanNoob

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No.



You will need the previously calculated 3 thick wires (instead of the 2) and an 8AWG ground.



Is there already a structure at location A?

How far is B from C?

Perfect. So the expensive wire just tripled because whatever could flow through one wire before has been split up and needs to go through three big wires now? I knew I didn't like science. The hits just keep on coming!

B and C are very far from each other with A between them. 800 feet or so.
 
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