I am a new PV householder - advice please. Unbalanced strings and wrong inverter

[juniperz]

what's this rasberry stuff about then?

I too want to look at stuff like this in August, as it seems there's been a fair few new products come along recently.

It is a very cheap computer with an ARM processor so it will not run Windows (well maybe a flavour of Windows 8) and runs linux, possibly Android.
"The Raspberry Pi model B board is supplied as the circuit board only, and comes without operating system, SD card, power supply, keyboard, case or cables. "
I think it could be used for monitoring an inverter like my Power One by adding a USB cable, a USB wifi adapter, an SD card with an operating system on it and a power supply (same as an android phone - micro USB plug). And a USB keyboard to set it up. And maybe a lego case! Then just leave it to consume something like 2 watts.

 

[Worcester]

Raspberry Pi | An ARM GNU/Linux box for $25. Take a byte! - A whole new can of worms - a linux computer for £25 ! (that's UK inc shipping)

Geeksville :1eye:

 

[Gavin A]

hmm luckily, one of my team is even geekier than me, and has a sideline in taking old laptops apart and making them work again, so this could be on.

 

[wstevew]

I have a Raspberry Pi. Not done much yet apart from boot up XBMC (Media Centre). I dont think it will become a useful android device as current android devices now have approx 4 x the memory of the Pi and at least 2x the processing power. More than enough power to monitor an inverter and upload to the web and some more.

For android the MK802. about twice the price of the Pi though.

http://www.engadget.com/2012/06/07/mk802-android-4-0-mini-pc-hands-on-impressions/

 

[Worcester]

I nearly hijacked this to talk about PI's so I've started a new thread instead!

p.s. I respect and understand the work you've done on your Android monitoring system for the SMA inverters.

 

[juniperz]

You have a point - strange. I don't think it is when the inverter is at its hottest (that seems to be an hour earlier) but it interesting that the Temperature takes a dip at the same time.
There is not tree or pole, but the scaffolding is still up, so the top lift does cast a shadow on the garage - though I think that is a bit later in the day. And that 3:05 dip is always back on the normal curve by 3:15...

Scaffolding still up because I have them coming back to take a look at the tiles.

I got my wife to check the temperature in the attic - 42 degrees C at 4:20pm. I would like to know what it is at 2pm, when the inverter is at peak temp.

I am a bit disappointed that after the peak of 3608W on 19th July, I haven't got above 3339W since, in spite of gorgeous weather.

While I am rambling, anyone sending data to PVOutput.org using Aurora Monitor on a Raspberry Pi??

Replying to myself. I think the inverter is limiting itself when the internal temp is above 70 - and it has been as high as 78, so I am generating less than that peak of 3608W before I was connected to PVOutput. I will try an electric fan when I finally get home tonight. (The irony of a powered fan and laptop to get electricity. And of generating less when the weather is the best of the year).
I have ordered a Raspberry Pi to play with though - 18 weeks lead time at RS and 5 weeks at Farnell - they are popular little things...

 

[sedgy34]

Replying to yourself
I think your thread is coming to an end

 

[Somecamel]

Re: Take advice n solar Panel Installation problems

Shameless Plug

 

[SolarCity]

Yep, and he's gone now. In just 1 hour he has made 5 posts - in one he praised the training course he had taken, in another he was bigging up HIS company Solawise and then in another he was praising the company that fitted the panels on his home - Solawise.

All of this in the kind of grammar that would make Jeremy Kyle raise a plastic eyebrow.

 

[Ecohouse]

This all sounds very wrong to me, I am a system designer. sound to me like you have 3 possible solutions. If the system is split my suggestion would be one central inverter for the main array and 2 Soladin slave inverters for the additional 4 panels or a Solar Edge inverter with individual power optimizers or micro inverters.

The twin tracker will be sufficient for spliit arrays but the loads are to unbalanced in this configuration.
Hope that helps

 

[Dan]

Don't mind me while I bump some threads in the solar PV forum. If they're not current or applicable topics, just ignore the threads; they'll drop off the page. If they are, feel free to chip in and chat solar stuff in the solar panels forum.