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Growatt Maximum Charge Current setting...

I had a hard time with pin one. Might be crossed... maybe.
Again, you could use 4 cables, as if you only had 4 batteries. Then try the Li again.
?????
Hi... Could you confirm that you found your battery to battery cables to be pin-to-pin with none crossed. Thanks!
 
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Ok, confirmed!!! Every wire straight through. NO cross wires, I triple checked 1 and 2 also 7 and 8.
Thanks very much for double checking the cables!! I know it was probably a hassle but much appreciated! At first (the other day) I was thinking in terms of Ethernet and it would of been a problem. But I was overlooking the fact that they talk in RS485 which is indeed a two wire transmission using differential voltages on just two wires. I used a provided USB to RS45 cable from S.S. to confirm that they were indeed using just pins 7 and 8. So in theory, having 1 and 2 crossed shouldn't matter (or 4 and 5 for that matter). But then again, who knows how things are wired internally.

Just to double check, you are using eg4-LifePOWER4 batteries (no screen) and how many?

Anyway, with more looking into the RS485 communications, I read that although it's a two wire protocol, it requires a common ground reference voltage of zero for all communicating nodes (i.e. inverter and batteries) to work best. I did not have my batteries grounded yet! They are supposed to be grounded by bolting them to the rack but S.S. sent me a rack with all the nuts in the wrong location for bolting the batteries in (non of the four holes on the battery flange lined up with the nuts). I didn't notice until all the batteries were in and wired. Not about to pull everything so just didn't worry about it (not like they were going anywhere). Didn't realize ground could impact the communications! Well, after getting everything grounded, the communications must of improved because I'm seeing higher draws from the solar panels now!!! Power charts are making more sense and I'm seeing solar power where you can see normal fluctuations (not flat-line stair steps as before). There is still some stair-stepping but it is always at well defined battery SoC levels (95%, 90%, etc.) and MCC (Max Charging Current) is being set automatically by the inverter also at well defined levels (25A, 50A, 100A (I could NEVER get it past 50A before)). I'm assuming this is to take it easy on the batteries when they are near the top end of charged. To see if it ever pushes past MCC of 100A (my panel array would probably at max put out 120A), I'll need to put a heavy heavy load on near maximum illumination part of the day.

So, I'm feeling better but need to do a bit more monitoring. If you have a few minutes... could you look at this chart and see if it looks now like reasonable behavior? Thanks!

Solar Energy Chart 11 with Comments.jpg
 
Well, see we both learned something about the batteries need grounded. Mine are, and yes lifpo4 non screen.
Yes, your chart represents/reflects the same behaviors I see in those conditions. ?
That's as far as I can help, at this point.
I'm very happy you got your system working!!
Thank you for the update, others will likely be able to use this information too.
 
That's what makes projects like this fun... learnings things! So moral of the story... ground the batteries (and cabinet) to the same ground as the inverter! Just like the instructions say to do! :rolleyes: So what are your battery dip switch settings? Mine are: Battery 1 (Master) - D D D D, Battery 2 - D U D D, Battery 3 - U U D D, Battery 4 - D D U D, Battery 5 - U D U D. Thanks!!!
 
Thanks very much for double checking the cables!! I know it was probably a hassle but much appreciated! At first (the other day) I was thinking in terms of Ethernet and it would of been a problem. But I was overlooking the fact that they talk in RS485 which is indeed a two wire transmission using differential voltages on just two wires. I used a provided USB to RS45 cable from S.S. to confirm that they were indeed using just pins 7 and 8. So in theory, having 1 and 2 crossed shouldn't matter (or 4 and 5 for that matter). But then again, who knows how things are wired internally.

Just to double check, you are using eg4-LifePOWER4 batteries (no screen) and how many?

Anyway, with more looking into the RS485 communications, I read that although it's a two wire protocol, it requires a common ground reference voltage of zero for all communicating nodes (i.e. inverter and batteries) to work best. I did not have my batteries grounded yet! They are supposed to be grounded by bolting them to the rack but S.S. sent me a rack with all the nuts in the wrong location for bolting the batteries in (non of the four holes on the battery flange lined up with the nuts). I didn't notice until all the batteries were in and wired. Not about to pull everything so just didn't worry about it (not like they were going anywhere). Didn't realize ground could impact the communications! Well, after getting everything grounded, the communications must of improved because I'm seeing higher draws from the solar panels now!!! Power charts are making more sense and I'm seeing solar power where you can see normal fluctuations (not flat-line stair steps as before). There is still some stair-stepping but it is always at well defined battery SoC levels (95%, 90%, etc.) and MCC (Max Charging Current) is being set automatically by the inverter also at well defined levels (25A, 50A, 100A (I could NEVER get it past 50A before)). I'm assuming this is to take it easy on the batteries when they are near the top end of charged. To see if it ever pushes past MCC of 100A (my panel array would probably at max put out 120A), I'll need to put a heavy heavy load on near maximum illumination part of the day.

So, I'm feeling better but need to do a bit more monitoring. If you have a few minutes... could you look at this chart and see if it looks now like reasonable behavior? Thanks!

View attachment 110370
Hello, i am having the same problem and solar was installed by a solar company(well so they claimed) I contact them to explain why I paid for a 3600watt system and is being capped at 2600watt and 50 amp charge
..at first I thought I had insufficient amount of panels so i went and bought 4 more (to add to the original 8 @450watt each) only to still be capped at 2600watt much earlier like 8:45am... Instead of 11:30am... The 12 panels are connected in 3 parallels which consist of 4 panels in series going into a combiner box and 6k growatt inverter(i see in manual that max pv input should be 5000watts but i now have 5400watts but i thought the panels would not get to that seeing I was not getting close to the 3600 from the 8 due to effeciency loss before I realise it was maybe capped not maxed) with a 10kwh 200ah lithium battery which is aimed as being off grid and the main utility is backup only when solar and battery is not available. Seeing that this conversation thread was 1 year ago and I am late in the game to ask questions but is it possible to explain the grounding that you mentioned? Is it the ground on the case of the battery and the ground on the case of the inverter you were talking about? See pictures attached. If so i looked on mine I they are left empty. (by the way my communication is from CAN on battery to BMS on inverter) And how did you connect your inverter ground and battery ground to a common ground as mentioned?
 

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