diy solar

diy solar

I'm confused... the PV watts won't go above 1.3k, SPF 12000T DVM with 3 x 48v 100 AH Lifepower 4 batteries, 18 x 320 Renogy panels

Bobby Cannon said:
When using LI mode, which means the Growatt Inverter is talking (or rather listening) to the EG4 batteries, this setting cannot be changed. It's controlled by the unit.

View attachment 98116
When charging at a limited 25A (1.3kw) from solar, this value reads 50A.
Click to expand...
Did you ever see it produces a lot more power before or it has been like this from the beginning?
What happen if you remove the communication between the Growatt and the EG4 battery and set it up as dumb battery?
 
Bud Martin said:
Did you ever see it produces a lot more power before or it has been like this from the beginning?
What happen if you remove the communication between the Growatt and the EG4 battery and set it up as dumb battery?
Click to expand...
When I had the AC on the panel it did jump to ~3000 at one point.

However, I did not mention the other issue so people wouldn't get distracted, but I have another 100ah battery coming Monday because the manual of the inverter says there should be 400 ah of battery and I only had 300 ah. But the batteries would go into ALM and the inverter would shut off when the inverter was only on battery.
 
OK, so updates. I tested each string individually. Meaning I turned off my PV combiner, disconnected all strings then I connected each string individually to ensure that each of them could deliver voltage and current. I tested each string individually at the Growatt panel. All of them, at the time of testing, was delivering approximately 9-11 amp each string. This means that I should have at least the ability to hit ~60 amps of charge / usage.

The inverter was stuck only pulling 24-25amps (1.33kw). This is literally only 2/2.5 of the 6 strings that are available. Also, after the end of the day my battery was a measle 60% charge... even though it had plenty of solar all day to charge... Crazy. The problem is it was a very humid day, and we have a large dehumidifier that kicked in many times throughout the day.

I have the parts installed so I can put the AC on the system. We'll see when the AC starts pulling ~3-3.5kw from the Inverter if the inverter will try and pull more from the panels.

Oh, and we have another battery being delivered today so I'm excited to see if the SPF 12000T DVM can run the AC on just battery (no grid / no solar). Currently if I try to run the AC and house (~3-4kw of AC) the system will shut down and all batteries will go into ALM (alarm).

Stay tuned for more!
 
acdoctor said:
I would love to know if the charge rate goes up when you add the other battery.
Click to expand...
I don't think it will. It turns out that the Growatt listens for the EG4 "master" battery. However even though I have 1 battery in "master" mode and the other in unique address, the other batteries never communicate. Now if I put all batteries in unique addresses then use the software tool to read them, they will all communicate. In the proposed master battery with all slave batteries, the slave batteries don't actually communicate which means the Growatt couldn't know about them. Adding more batteries that it won't know about, shouldn't / won't change how it works.
 
Have you tried charging the battery manually from the growatt with communication disconnected?
 
Bobert said:
Have you tried charging the battery manually from the growatt with communication disconnected?
Click to expand...
We'll I've tried to run it in US2 mode (no comms mode) but when I do the inverter thinks the battery is 100% even though it at the time was around 70%.

So no, I haven't figured out the magic settings to make US2 to work. I'm thinking that is what I'm going to have to figure out.
 
Maybe that’s where the problem lies. If the growatt only thinks you have 1 battery the recommended charge rate in the specs of EG4 is really low.
Don’t your growatt have a non lithium self defined setting?
Is there no guidance from SS on settings to allow the growatt to communicate with the other batteries. If not the coms is worthless.
My understanding of coms is if any of the BMS sees an issue it communicates to reduce or stop charging. If it is only listening to one the rest could be in trouble and number one be completely happy.
 
Bobby Cannon said:
We'll I've tried to run it in US2 mode (no comms mode) but when I do the inverter thinks the battery is 100% even though it at the time was around 70%.

So no, I haven't figured out the magic settings to make US2 to work. I'm thinking that is what I'm going to have to figure out.
Click to expand...
For the sake of testing I would discharge the batteries until the growatt would charge them to be sure it can actually make full use of your array. Obviously you have a lot of irons in the fire with another battery coming and now might not be the best time for that experiment. If the issue persists though I would want to be sure that you unit can actually utilize your full array before messing to much with com settings.
 
I am in another thread where several people have EG4 batteries and the new EG4 AOI and are having coms trouble. @RichardfromEG4 thinks it’s a cable problem. I don’t know if the cables come with the batteries or the inverter?
 
acdoctor said:
I am in another thread where several people have EG4 batteries and the new EG4 AOI and are having coms trouble. @RichardfromEG4 thinks it’s a cable problem. I don’t know if the cables come with the batteries or the inverter?
Click to expand...
The inverter communicates because if I remove the cable it will "Error 20". The communication is good.

However, based on my research of monitoring the RS485 link between the Growatt and EG4 batteries, only 1 battery sends out data. The rest do not.

I don't think this has anything to do with my problem but maybe it is.
 
RichardfromEG4 said:
We are making the cables on site at this point and including them with the inverter. We haven't been able to duplicate the error with us making the cables at the distribution site since we started terminating both ends of the PIN OUT. If you are having this issue give SS a ring to get a new cable sent out or you can make your own (PIN 1/2 -battery to PIN 3/5 -inverter).
Click to expand...
I don't understand this because if I plug in the cable from the BMS to the Inverter it will not error 20. But are you suggesting that the cable being plugged in may not error 20 but still not be communicating?

The reason I feel it must be working is because the battery percentage, cut offs, etc are working as expected in LI mode (setting 5). So how could communications not be working.

BTW, I'm using a standard network cable between the Inverter and the main battery (master mode, all switches down).
 
RichardfromEG4 said:
We are making the cables on site at this point and including them with the inverter. We haven't been able to duplicate the error with us making the cables at the distribution site since we started terminating both ends of the PIN OUT. If you are having this issue give SS a ring to get a new cable sent out or you can make your own (PIN 1/2 -battery to PIN 3/5 -inverter).
Click to expand...
Also does this mean

* Battery Pin 1 -> Inverter Pin 3
* Battery Pin 2 -> Inverter Pin 5

Also is this true for the Growatt SPF 12000T DVM?
 
Bobby Cannon said:
Also does this mean

* Battery Pin 1 -> Inverter Pin 3
* Battery Pin 2 -> Inverter Pin 5

Also is this true for the Growatt SPF 12000T DVM?
Click to expand...
The manuals do not agree.

The Growatt manual says pin 1 and 2 are data pins for the BMS port for the SPF 12000T DVM.
The EG4 manuals says pins 7 and 8 are the data pins for the RS485 ports for the EG4 Lifepower4.

But it has me thinking. Is the inverter considering a cable plugged in enough for the error 20 to go away... without having good communications? But if so then how does it know all the values unless they are defaults?

Interesting, I need to think more about this.

Growatt Manual
1655133499754.png

EG 4 Manual
1655133630231.png
 
Something else to consider. I powered down the inverter then turned off all batteries. Then I turned the back on but left the inverter in the "off" or wait mode. BOOM, the inverter pulled a full 40amps via the PV input.

1655134138487.png

Now during my time of monitoring the RS485 port between the Growatt and EG4 batteries I have noticed that there are times when the EG4 master battery will not chatter like it is supposed to. This happens no matter which of the 3 I choose to be the master battery.

I think I need to resetup my RS485 sniffer to monitor the comms.
 
You must log in or register to reply here.

Similar threads

Ryushin
It's Working!!! Sol-Ark 15K, 33.52kW with 67 Panels AC+DC PV, 25kW SOK Batteries - Photo Diary
4 5 6
Replies
117
Views
6K
Ryushin
Ryushin
C
Tiny House System Diagram - Please feedback! - Growatt 12000T DMV-MPV, 4x Jakiper 48V batteries, 8x 455W Jink Bifacials
Replies
5
Views
678
CubesAreShapes
C
Back
Top