Balcony solar PV

[Countrypaul]

How big are the actual cables?

[Joeboy]

How big are the actual cables?

25mm sq 170A according to the purchase sheet.

Anecdote time. I had a small section of smaller dia cable I fitted. One size down so likely 20mm sq. Man that bit was warm to the touch. No idea how I fitted that but it was a lesson in cross section heat flow. Replaced it with a cut off from the most recent 25mm sq purchase and it immediately plummeted in temperature

These thoughts lead me into territory I'm not overly familiar with. Resistance in batteries, cable run quality etc. More so though is the thought of power flowing from PV and then disappearing into the pool that is the battery. I guess I'm hydraulic thinking again. Want to get all I can out of this system as it's pretty much complete and the upcoming ashp will add its own demands which I'd like to trim as much as possible.

[Countrypaul]

Sorry Joe,

I can't quite understand how everything is connected, there seems to be lots of bits of information rather lie a jigsaw without a picture of how the finished product is supposed to look. Any chance of a diagram showing the details? or a pointer to one if you have already posted one and I've missed it.

[Joeboy]

Sorry Joe,

I can't quite understand how everything is connected, there seems to be lots of bits of information rather lie a jigsaw without a picture of how the finished product is supposed to look. Any chance of a diagram showing the details? or a pointer to one if you have already posted one and I've missed it.

Understood, I'm far away from it all and dont carry that stuff on my phone. This afternoon has been excellent as multiple thinking moments. I'd forgotten that I had info on cables. I've run them flat out in the best days (3 in a row) that Summer could throw at us and even peaking over 8kW for extended periods we had no hot cables, mildly warm at best . Thank you for the 170A pointer.

I then begin to think about quality cables. Multistrand, imports of varying weights. When I bought I went for cables marked as welding cables. Good chance of better quality copper, build and insulation in a welding cable as killing the operator with shonky gear gets you straight into court.

A bit caveman in thought but as with known cable heat it's a strong indicator that we'll be OK at 150/85, up 25A potentially.

Again, thank you for that 170A direction, much appreciated.

[Countrypaul]

I remember reading a Vicron document about connecting multiple power sources to multiple power consumers using bus bars. I think it was multiple charge controllers to multiple sets of batteries but am not certain. I do remember that they advised against putting all of each kind at one end, and if ircc they suggested alternating the two types as that minimised the load on any single part of the bus bar. You might be in a similar position. Unfortunately I cannot remember the document name/title so not sure what to search for.

When at work (software development/consultancy) we often foound that explaining a problem to someone else, even if they did not understand it, resulted in a light bulb moment of how to approach or solve the problem even with little to no input from the person it was explained to.

I on;y asked about the cable size since it seemed an obvious potential limitation, I had little idea of where it would lead to so hopefully it has helped.

[chris_n]

I remember reading a Vicron document about connecting multiple power sources to multiple power consumers using bus bars. I think it was multiple charge controllers to multiple sets of batteries but am not certain. I do remember that they advised against putting all of each kind at one end, and if ircc they suggested alternating the two types as that minimised the load on any single part of the bus bar. You might be in a similar position. Unfortunately I cannot remember the document name/title so not sure what to search for.

When at work (software development/consultancy) we often foound that explaining a problem to someone else, even if they did not understand it, resulted in a light bulb moment of how to approach or solve the problem even with little to no input from the person it was explained to.

I on;y asked about the cable size since it seemed an obvious potential limitation, I had little idea of where it would lead to so hopefully it has helped.

That to me is the whole point of forums of this type, while you are putting your ideas or work into words you have to spend more time thinking over what you are actually doing and what you hope to achieve. Often leads to a Eureka moment!

[Fintray]

I remember reading a Vicron document about connecting multiple power sources to multiple power consumers using bus bars. I think it was multiple charge controllers to multiple sets of batteries but am not certain. I do remember that they advised against putting all of each kind at one end, and if ircc they suggested alternating the two types as that minimised the load on any single part of the bus bar. You might be in a similar position. Unfortunately I cannot remember the document name/title so not sure what to search for.

Wiring Unlimited page 37/8.

[Joeboy]

I remember reading a Vicron document about connecting multiple power sources to multiple power consumers using bus bars. I think it was multiple charge controllers to multiple sets of batteries but am not certain. I do remember that they advised against putting all of each kind at one end, and if ircc they suggested alternating the two types as that minimised the load on any single part of the bus bar. You might be in a similar position. Unfortunately I cannot remember the document name/title so not sure what to search for.

When at work (software development/consultancy) we often foound that explaining a problem to someone else, even if they did not understand it, resulted in a light bulb moment of how to approach or solve the problem even with little to no input from the person it was explained to.

I on;y asked about the cable size since it seemed an obvious potential limitation, I had little idea of where it would lead to so hopefully it has helped.

Thank you, I've definitely split how the load(s) hit the batteries. Not to say I won't look to check for heatspots and improve cabling if need be once Spring rolls around again. I spent morning booking bus rides to Cappadocia along with digs and balloon rides too. Mind was brought back into focus with that simple cable size query.

I've got time on my side as it's 5 months before we'll see the big loads incoming again. 6 months before consistent large inflows. I'm willing to shell out to obtain the hoped for 0.75MWh extra across the year. Hoping too for Xmas discounts on a Victron.150/85. Best price so far for posterity within UK is £353 including post.

[Countrypaul]

I remember reading a Vicron document about connecting multiple power sources to multiple power consumers using bus bars. I think it was multiple charge controllers to multiple sets of batteries but am not certain. I do remember that they advised against putting all of each kind at one end, and if ircc they suggested alternating the two types as that minimised the load on any single part of the bus bar. You might be in a similar position. Unfortunately I cannot remember the document name/title so not sure what to search for.

Wiring Unlimited page 37/8.

Thanks Fintray,

I was thinkmg mainly of section 4.10 (p39), but then also ... well the whole rest of the document
Just in case there are multiple revisions, this is the one I loooked at now: https://www.victronenergy.com/upload/do ... pdf-en.pdf

[Joeboy]

That's the first week in for the Hoymiles microinverter in Turkey. It has done its job with no drop out so I've neatened it up and calling it done. We continue to run the 28W big blue folding panels on all the 5V batteries, lights etc so it's going well.

Not seen a golfball sized hailstorm in a few years here but should be OK on the vertical with an overhang.