Solar PV advice

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Fintray
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Re: Solar PV advice

#171

Post by Fintray »

I can't see any problems with that; if you can, make sure everything is torqued to the correct amount.
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Richard77
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Re: Solar PV advice

#172

Post by Richard77 »

Fintray wrote: Wed Mar 05, 2025 7:38 pm I can't see any problems with that; if you can, make sure everything is torqued to the correct amount.
Thanks... electrician will fit it all, so will remind them. I will make up the cables myself though.

Just thought I read that every cable length should be exactly the same length. But my longest run needs to be 1.2m, so can't butcher my original 2m cables to all be the same lengths :(
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nowty
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Re: Solar PV advice

#173

Post by nowty »

Don't worry too much about slightly different cable lengths, no system is exactly perfect. Who cares if your using say 1% or 2% more from one battery than the other, if you make a potentially shorter cable longer just for the sake of being equal, you will end up wasting more energy overall. The batteries themselves won't be perfectly equal either.

Also re-torque up a month or two after going operational, its surprising how stuff beds in from the temperature cycling.
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pudding
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Re: Solar PV advice

#174

Post by pudding »

Its all the cables to the batteries that should be the same length so each battery sees the same resistance/voltage drop, it doesn't matter if the Keto to inverter cable length is different from the battery ones, that's fine.
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Richard77
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Re: Solar PV advice

#175

Post by Richard77 »

Cheers nowty....
pudding wrote: Wed Mar 05, 2025 8:14 pm Its all the cables to the batteries that should be the same length so each battery sees the same resistance/voltage drop, it doesn't matter if the Keto to inverter cable length is different from the battery ones, that's fine.
Thanks pudding... I was thinking along the same lines. Think I just wanted some reassurance before I start cutting!
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Re: Solar PV advice

#176

Post by Richard77 »

Trying to make the cables up and these 35mm² lugs will not fit on these 35mm² cables!!!

<Loud scream>
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nowty
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Re: Solar PV advice

#177

Post by nowty »

Richard77 wrote: Thu Mar 06, 2025 11:18 am Trying to make the cables up and these 35mm² lugs will not fit on these 35mm² cables!!!

<Loud scream>
Cut a few strands off the wire until it does fit.

If your using welding cable which has many strands, they sometimes fluff up a bit and can be difficult to get in.
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Stinsy
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Re: Solar PV advice

#178

Post by Stinsy »

Richard77 wrote: Thu Mar 06, 2025 11:18 am Trying to make the cables up and these 35mm² lugs will not fit on these 35mm² cables!!!

<Loud scream>
The other problem is more common: where "35mm²" is really 25mm² and the lugs are therefore loose!
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Richard77
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Re: Solar PV advice

#179

Post by Richard77 »

It doesn't even seem close to going on... :surrender:
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Re: Solar PV advice

#180

Post by pudding »

Any pics? Shouldnt be that far out?
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