Growatt Maximum Charge Current setting...

[Darren67-72]

I understand your frustration. Your state of charge should be bouncing from 99% to 100% with the sernerow you described.
Bummer.
Did you try oso with Li setting? It's my last suggestion, and hope you keep us informed on this issue.
I'll keep looking at this issue, for something I may have missed.

 

[jsl10]

I understand your frustration. Your state of charge should be bouncing from 99% to 100% with the sernerow you described.
Bummer.
Did you try oso with Li setting? It's my last suggestion, and hope you keep us informed on this issue.
I'll keep looking at this issue, for something I may have missed.

No, I hadn't tried OSO. I'll go do that right now...

 

[Darren67-72]

I recieved a call from a guy today, having this same issue with one of his two inverters. His frustration is, it is his new inverter that has the limit. That doesn't make sense, unless his newest inverter is actually built before his older one.
You never know the program dates when ordering. Anyway, good luck.

 

[Darren67-72]

It should be noted, if your batteries are near full charge, they will never pull 50 or 60amps anyway. The inverter will taper the charge down near full for a slower top off. This is the proper way charge controler work.

 

[jsl10]

I changed setting 14 to OSO, turned the inverter off, waited and then back on. I did not power cycle the batteries though. Sadly, nothing changed. Your guy is getting the same capped solar power with Li setting??? If so, he should contact Ethan Rogers at Signature Solar and let him know. Maybe there is a problem in the newer inverters (new doesn't always mean better!). My inverter isn't all that old either. Maybe with more complaints, there could be a firmware fix.

 

[jsl10]

Also, does your guy have the same two Growatt inverters and using the same settings on both?

 

[Darren67-72]

I'm sorry I could not help either. But, I'm never done looking for answers until we get it figured out.
This guy has the same issue with a different inverter brand all together.
Good luck, good day!!!

 

[jsl10]

Thanks for all your help in trying to figure out this mystery! I'll continue to post here any new things tried and results. In the mean time, I'll switch back to US2 settings.

 

[jsl10]

I notice in the battery manual it says it uses pins 7 and 8 for data on it's communication port. RG45B spec. says that pins 7 and 8 are Bi-Directional Transmit + and -. So that's fine. I pulled all the battery to battery cables (the little ones supplied with batteries). I tested all four on my Ethernet cable tester. For three of them, it shows pins 1 and 2 (normal Transmit + and -) cross split. All the other pins show fine. If they are not using pins 1 and 2 that should be fine. Maybe they crossed them deliberately to eliminate potential noise. Anyway, on ONE of the cables it also shows pins 4 and 5 also as a crossed split pair! The RG45B spec says that pins 4 and 5 (along with 7 and 8) are used also for Bi-Directional Transmit + and -. So effectively pins 4 and 5 are the same as pins 7 and 8 and probably all feed into some communication chip in the battery. If like all Ethernet, if all batteries "see" all traffic on the cables (ignoring all but what's addressed to them) having pins 4 and 5 on a single cable crossed, could screw up the entire daisy chained communication link. Wouldn't it? I know checking cables is a long shot but the fact that a single cable is different than the others makes me wonder! Thoughts???

 

[Darren67-72]

I have some thoughts, (ha ha) you are almost talking completely over my head but, what little I know.... others here have said growatt cables are hit and miss. So, you might be on to something. The 50amp limit I had, sounds the same but, you may have a bad cable(s).
While I was on "US2" my batteries would get out of balance every day. I use at least 50% of capacity every night. (I have 30k batt.)
Now on "Li" they stay balanced. Point being, let me test my known good cables and I'll get back with you. So as I can.

 

[jsl10]

I figured testing the cables was a VERY big long shot but I pulled all the short battery to battery cables off (not being used in US2 mode anyway) and dug out an RJ45 tester I had. And sure enough, out of five cables showing only pins 1 & 2 crossed, ONE cable also showed pins 4 & 5 crossed. Pins 4 & 5 just happen to be the same data as pins 7 & 8. This would effectively short out the entire communication daisy chain. So who knows what the inverter was thinking about the batteries. It probably didn't have a clue so to be safe was dishing out the solar power with a thimble! At least that's my theory. I'll have to test tomorrow. I'll let you know!

 

[Darren67-72]

Wow, I'm too old for that crap... I need a magna fine glass and 4 hands for that job.
I tested 5 of my six (blue) rs485 cables. Just could not get myself to do the last one. They are all straight through. Ie: Blue to blue, #1 to #1, ext.

 

[Darren67-72]

No fancy tester here. Hope you can get a mental picture of that. Using my belly and knees together.

 

[Darren67-72]

Oh crap. I only tested wire to wire, that is end to end. 1,4,6,8 I did not check all 8 pins.

 

[Darren67-72]

Typo 2 4 6 8

 

[jsl10]

Ya, I hear ya! But that's where a tester comes in. It can check for split-pairs. That's odd that your short cables (supplied with batteries?) don't show pins 1 and 2 crossed. All mine do. Of course, on the tester even that seems intermittent. Sometimes they are crossed and other times not. Might be my old tester. But on the bad wire, it's very consistent in saying 4 & 5 are crossed. So I figure 1 & 2 must be deliberate. Almost feel like ordering a set of new short cables!

 

[Darren67-72]

Ok I check 12345678 give me a few minutes.....

 

[Darren67-72]

I know you are going to think I'm crazy but, my cables came in the box with each battery (each separate) and none of the pins cross. Best I can tell, with my sharpest point tester, all pins go straight through. Tested all 8 pins.

 

[Darren67-72]

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.
?????

 

[jsl10]

Good job testing all your cables. I know what you mean about needing a magnifying glass. Previously I tried just testing with my multi-meter but the meter's test leads were to thick to make contact with the little pins in the connectors. Anyway, with five batteries I only needed four of the short ones that came with them (I used my own cable to go to the inverter). So I have an extra! All five of my cables showed pins 1 and 2 crossed (at least some of the time on my old tester). Since pins 1 and 2 are used for different data, that might be deliberate to reduce noise. Anyway, I already plugged the short cables back in with the "bad" one tossed aside and replaced with my spare! I'll re-set the battery type to Li tomorrow when I get enough sun to tell if it's being capped still. I REALLY hope this fixes it.