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tomqu7 Senior Member Joined: 09/11/2012 Location: AustraliaPosts: 168
Posted: 10:46pm 30 Dec 2012
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ts still unclear what you are talking about or how this is setup.
Are these PV strings all parallel connected, or do they go to an inverter with 2 isolated inputs.
As it make little sense to have 2 different voltage strings.
Also what inverter is in use here, because 800 volt seems awfully bloody high, and many inverters dont go above 550 volts max.
To me something is cocked up here either you or your system or both.
Edited by Downwind on 30 December 2012 at 3:50am
the pv 1 string and the pv2 string connects to a macsolar 5 kw inverter
one string is 12 panels and one string 13
the inverter takes 40-60 % over voltage the 4 ports on the bottomn of the inverter are occupied
one string is 200 volts one is 400 volts corection
one 1700 watts one 800 watts
they sit on on my roof 4 rows of 5 panels ( 1 row 7 1 row 8)
so may be they forgot to connect the 2 halves
so one half is 3 kw other half with the 10 panels 2 kwEdited by tomqu7 2013-01-01
MOBI Guru Joined: 02/12/2012 Location: AustraliaPosts: 819
Posted: 12:26am 31 Dec 2012
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Four rows of 5 panels = 20 panels.
1 row 7 and 1 row 8 = 15 panels.
Something doesn't make sense here.
Are you able to do a circuit sketch of what you think you have and post a photo of the sketch so that we can better understand what you are trying to do.
I suspect that your two strings of panels are then connected in parallel, but the string voltages suggest that strings are made up of different voltage panels to one another.
We'll get to the bottom of this yet.
David M.David M.
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333
Posted: 12:40am 31 Dec 2012
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OK, so now volts have become watts.
Or is it just me that's confused..........??
Mate you need to slow down on what you post and actually get your facts correct, you can post as much as you like just get the information correct when you post, or you come across as a total nutter??
As for the macsolar 5 kw inverter, i would not know that inverter if it bit me on the ass, so do some research on the inverter information and post the details or at least post a link to the inverter data on the forum.
We or at least i am, a lazy bugger and will check a link, but wont go off searching for information because you are to lazy to do it yourself.
It comes back to giving the correct information and the tools to work with, then we can give answers that might help you.
Now just on a guess and from the bread crumbs of information i can understand, you imply you THINK you are missing about 1/3 of capacity.
So this might result from one string being at 400v and 1 string at 200v, this COULD mean the inverter never sees the 200v string which is 1/3 of the system.
Cause....... perhaps the way the inverter work.
Some inverters have 2 pairs of inputs but both sets are looped with a bus bar inside feeding to 1 MPPT.
Now some other inverters have 2 pairs of inputs, and each pair with its own MPPT (2 x MPPT), this type of inverter you can have 2 strings at different voltages, where with a single MPPT you CAN NOT
If your inverter is a single MPPT then 1/3 of your panels will never produce enough voltage compared to the other 2/3 to reach the inverter, as the blocking diodes in each panel will be working overtime to prevent 200v being pushed back into the 200v string.
Do you understand? either do the research yourself, or give us links to information to work with, or its just underpants answers we can give you..
Edited by Downwind 2013-01-01Sometimes it just works
Do you have a voltage regulator between the battery bank and solar panels? If so check the specs on the voltage regulator. No doubt you will be able to connect the panels in parallel using blocking diodes or perhaps if the regulator can handle yo can connect the panels in series (max voltage in regulator 37.26 + 28.9).
Thankyou.
Regards Darcy Randall, Perth Western Australia
tomqu7 Senior Member Joined: 09/11/2012 Location: AustraliaPosts: 168
Posted: 02:25am 06 Jan 2013
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s still unclear what you are talking about or how this is setup.
Are these PV strings all parallel connected, or do they go to an inverter with 2 isolated inputs.
As it make little sense to have 2 different voltage strings.
Also what inverter is in use here, because 800 volt seems awfully bloody high, and many inverters dont go above 550 volts max.
To me something is cocked up here either you or your system or both.
ONE STRING IS 400 VOLTS 600 WATTS
OTHER STRING 200 VOLTS 300 WATT THIS IS THE RATIO
ONE STRING IS 13 PANELS OTHER STRING 12 PANELS
EACH STRING GOES TO ONE PORT IN MAC SOLAR 5 KW
ONLY DOING 20 KW PER DAY
ON THE ROOF THERE ARE 2 ROWS OF 5 PANELS 1 ROW OF 7 1 X ROW 8
Downwind Guru Joined: 09/09/2009 Location: AustraliaPosts: 2333
Posted: 04:01am 06 Jan 2013
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Tom,
Again you are hijacking someone elses thread and its best to start your own thread on your own subject matter.
Did you read my last post on inverters and MPPT and how it can make a difference from one system to the other.
You still have not given any information about your inverters or links to data on your inverters.
All you do is quote the same garbage and no information to work with, expecting a miracle answer.
Please give some better information and links to data on your inverters to work with.Sometimes it just works
tomqu7 Senior Member Joined: 09/11/2012 Location: AustraliaPosts: 168
Posted: 07:09pm 06 Jan 2013
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re differnt voltages
u can use micro inverter I think and use different panels
they are still a bit expensive
aprox 180 each
readyakira Senior Member Joined: 17/07/2008 Location: United StatesPosts: 114
Posted: 10:04am 07 Mar 2013
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ok so, we have a total of 25 panels... a row of 5 a row of 5, a row of 7 and a row of 8. together they are wired as a series of 12 and a series of 13?
So, first they should be a lot more equal in output then what they are if there is only one panel difference in the two strings. so either you have a bunch of mismatched panels or there is a wiring fault somewhere. (my best guess given your post.)
That would be my starting point first and foremost.
Second how about at least a model number for that GTI you are using.
The panels go directly to the GTI and not some battery bank first is appears. Ok then we NEED at very least the model of that GTI.
(and I consider myself a n00b..... Who knew?Don't you think Free/Renewable energy should be mandatory in new buildings?
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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