External limiting an GTIL2 SUN-1000G2 with raspberry

Btw for accurate monitoring logging with Cts in series or parallel, I wouldn’t use the information off of these inverters. They are cheap things. I use an Iotawatt for monitoring/logging. You could get an emporia but their graphing is no where near as accurate/detailed as Iotawatt
 
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Here I have a test program for you, with which you can test the communication to the inverter.
Hello everybody,
Thank you so much for your example.
I connected the ESP-01 directly (without MAX3232). It works well.
Do you know how to get more information? F.e. which register does contain "Grid Watt" information?
 

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Attachment official RSS protocol in chinese language (needs to be translate with google to english)
I translated document, did some tests, my summary next:
It's a huge headache. When inverter processes modbus request, it stops production, so you cannot poll the device very often(every 10 seconds), because it can't go to needed performance.
I think registers 109-116 are work, but we can't see values cause inverter stops the work in process request.
 
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Reading the Inverter data and setting the output power works (via RS232). Thanks for the fine information in this thread that helped me.


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Hi, does your solution work til now?
I controlled my SUN1000 GTIL2 by use of a digital potentiometer and a raspberry pi. The solution worked for several month but recently the dPot died and I´m looking for a more stable solution.
regards, Walter
 
Sorry for writing in german, but the following text is an answer to a private message of member @mondurlauber. He has disabled private messaging, so I can't answer him directly.

I will do an answer here later in english with pictures of my actual solution (digital potentiometer on a Raspberry Zero W)

######################### ATTENTION GERMAN LANGUAGE :) ###################
Hi,
Das mit der 0-2V Regelung war nicht stabil.
Ich hab dann auf "Digitalpoti" umgestellt.

Von Anfang an:
Man muss den Inverter ffnen und intern das Kabel einer der beiden externen Buchsen (internal/external Limiter) umstecken auf den freien 3-Pin Stecker gleich daneben. (Ich schau ob ich noch Bilder habe)
Dann das externe Kabel, da normalerweise zur Messzange geht (mit dem Metall-Schraubstecker dran) abschneiden und ein Poti dran (0-10k).
Jetzt ist "manuelles" Regeln 0-1000Watt mglich.
Da das natrlich nicht von einem Raspberry/Arduino/sonstiges gesteuert werden kann hab ich ein digitales Poti an einem Raspberry Zero W angeschlossen und regle das jetzt so. Geht aber mit Arduino genauso, das Digitale Poti ist ein SPI Gert wo man einfach 0x00 bis 0xFF hinschickt. (echo -ne "\x00" > /dev/spidev0.1)

PMODDPOT heisst das Digitale Poti.
https://www.conrad.at/de/erweiterungsmodul-digilent-410-239-1526982.html
Hallo,

ich schreibe jetzt auch mal in deutsch, weiß aber eh nicht, ob du überhaupt in diesem Forum noch aktiv bist.
Ich hatte auch eine Lösung mit diesem dPot (AD5610) umgesetzt, die auch für einige Monate ganz gut lief. Leider ging das dPot vor einige Tagen kaputt, der Wiper hat wohl keinen Kontakt mehr; vielleicht war der Strom zu hoch.
Hast du deine Lösung mit dem dPot zum Laufen bekommen und funktioniert sie noch immer?
 
Hallo,

ich schreibe jetzt auch mal in deutsch, weiß aber eh nicht, ob du überhaupt in diesem Forum noch aktiv bist.
Ich hatte auch eine Lösung mit diesem dPot (AD5610) umgesetzt, die auch für einige Monate ganz gut lief. Leider ging das dPot vor einige Tagen kaputt, der Wiper hat wohl keinen Kontakt mehr; vielleicht war der Strom zu hoch.
Hast du deine Lösung mit dem dPot zum Laufen bekommen und funktioniert sie noch immer?
If the wiper current is the problem, you could use 4 modules at the same time : 2 string parallel from 2 in series.
 
If the wiper current is the problem, you could use 4 modules at the same time : 2 string parallel from 2 in series.
I‘m not completely sure, if the current was to high. I use a resistor of 110 ohms in series to limit the current. Are you using your described solution, sounds theoretically ok? And when for how much time? I‘m looking for a stable solution.
 
I‘m not completely sure, if the current was to high. I use a resistor of 110 ohms in series to limit the current. Are you using your described solution, sounds theoretically ok? And when for how much time? I‘m looking for a stable solution.
I don't use this myself. But if it worked with one module for a given time, I would suspect it would work longer ( how much is the question ... ) if you split the power generated in the dpot over 4 dpots. I don't directly see a better/other solution ...
 
Hi, my 2kW unit seems to have some "problems". I really need some helps to verify it and identity the possible cause...

Basically, my unit may suddenly shut itself down after outputting 500-600W for around 3hrs. The LCD goes black and a sparkling sound from the AC plug. Not sure it is due to short circuit or due to quick disconnect.
However, it is not completely dead. If I disconnect the AC, wait for few minutes, then reconnect. The inverter LCD will turns on and works again normally, for a few hours.

One of the possible cause I could think of is overheating. Interestingly, the fan on my unit doesn't spin. When the load is over 1kW, it may spins for like a few seconds, then will turns off completely.

When outputting 500W, the fan on my unit is off. After rebooting it from the shutdown, the temperature shown on the LCD is around 50degC, and the casing is relatively warm to the touch.

Is the temperature readings normal?
Is the fans on my unit faulty? Has anyone encountered similar problem?
 
Hi, my 2kW unit seems to have some "problems". I really need some helps to verify it and identity the possible cause...

Basically, my unit may suddenly shut itself down after outputting 500-600W for around 3hrs. The LCD goes black and a sparkling sound from the AC plug. Not sure it is due to short circuit or due to quick disconnect.
However, it is not completely dead. If I disconnect the AC, wait for few minutes, then reconnect. The inverter LCD will turns on and works again normally, for a few hours.

One of the possible cause I could think of is overheating. Interestingly, the fan on my unit doesn't spin. When the load is over 1kW, it may spins for like a few seconds, then will turns off completely.

When outputting 500W, the fan on my unit is off. After rebooting it from the shutdown, the temperature shown on the LCD is around 50degC, and the casing is relatively warm to the touch.

Is the temperature readings normal?
Is the fans on my unit faulty? Has anyone encountered similar problem?
I think your guess is right, that it seems like it is over heating. I run mine at around 250watts each and the fans go on and off frequently. Sounds like the issue with the temperature sensor control having some problem. Maybe check if the temperature sensor has any issues like not mounted where it suppose to be or lose wire or etc. If still not sure then definitely return it.
 
I think your guess is right, that it seems like it is over heating. I run mine at around 250watts each and the fans go on and off frequently. Sounds like the issue with the temperature sensor control having some problem. Maybe check if the temperature sensor has any issues like not mounted where it suppose to be or lose wire or etc. If still not sure then definitely return it.
Thanks for your info! I think my issue is (somewhat) solved. Just an update and maybe can help someone if encountered similar issue.

I think the fan controls in my unit is broken or something. Fans are working fine with I powered them externally. I can measure 3V-5V at the fan connectors (with fan unplugged) when the inverter is outputting 500W, but the fan just doesn't spins. Also, i noticed there is a blinking blue LED inside (see attached image), not sure what it means.
1639557271501.jpeg

So i unplugged the fans and powered them externally at 8V using a raspberry pi power supply + boost converter. There are three fans, two 12V fans blowing air into the unit, and a smaller 9V fan to cool the MOSFETs' heat sink. I just remove one of the screw for the 12V fan, and tuck all the wires through it.
1639557249679.png

Tested few days with the fans powered externally, the inverter stays below 40degC, and no longer has the weird shutdown. :):)
 
Thanks for your info! I think my issue is (somewhat) solved. Just an update and maybe can help someone if encountered similar issue.

I think the fan controls in my unit is broken or something. Fans are working fine with I powered them externally. I can measure 3V-5V at the fan connectors (with fan unplugged) when the inverter is outputting 500W, but the fan just doesn't spins. Also, i noticed there is a blinking blue LED inside (see attached image), not sure what it means.
View attachment 26627

So i unplugged the fans and powered them externally at 8V using a raspberry pi power supply + boost converter. There are three fans, two 12V fans blowing air into the unit, and a smaller 9V fan to cool the MOSFETs' heat sink. I just remove one of the screw for the 12V fan, and tuck all the wires through it.
View attachment 26626

Tested few days with the fans powered externally, the inverter stays below 40degC, and no longer has the weird shutdown. :):)

The fan issues with these inverters is real.. on that Facebook group, I have shown how I fixed mine and others have shown other ways
 
Hi all, based on the article


I build a SMD circuit board, 50 x 24mm, which can control two Solar grid inverters using the potentiometer interface, 0-3.3V => 0- 100%
( VCC = 3.3 Voltage, + 2 Inputs to control + 2 output connectors) - testet currently on GTIL 1000 but only up to 250W - because only lean out by a friend.

If interested let me know via PM.
 
Hi Moritz71,

Based on your previous post I can't figure out how you set the output power of the sun inverter. Are you using a Modbus register for that? Which one is?

Many thanks
 
Hi Moritz71,

Based on your previous post I can't figure out how you set the output power of the sun inverter. Are you using a Modbus register for that? Which one is?

Many thanks
Hi , I used the Potentiometer Input connector, and connect that to my PCB circuit I built - it works nice and the sun inverter can be controlled nearly linear with 0 .. 3.3 V Input here ....
 
ok, I tried some things myself just now.

Applying an external voltage doesn't do anything with my GTIL2.
I did hope to control it using an DAC as you do it with DCDC converter feedback resistors etc.

Then I tried limiting using a fix 1k resistor, that dropped the power from 450 to 340W.
But the current! 300mA through 1k, that explains why digital Rpot die, it's way too much for them.

I suppose nobody did examine the controller PCB any further?
I can not get the PCB out right now, but it would be interesting to see where the 2pin connector is connected to, I could not beep it with my multimeter today, not enough time to do so :/
 
ok, I tried some things myself just now.

Applying an external voltage doesn't do anything with my GTIL2.
I did hope to control it using an DAC as you do it with DCDC converter feedback resistors etc.

Then I tried limiting using a fix 1k resistor, that dropped the power from 450 to 340W.
But the current! 300mA through 1k, that explains why digital Rpot die, it's way too much for them.

I suppose nobody did examine the controller PCB any further?
I can not get the PCB out right now, but it would be interesting to see where the 2pin connector is connected to, I could not beep it with my multimeter today, not enough time to do so :/
Nice piece of information NikA.

I was hoping this pmod dpot would be a good solution. It can only handle 4.7mA continuous.

"Care must be taken to ensure that current flow between the wiper terminal and either terminal A or B must be
limited to a pulsed ±20mA or a continuous 4.7mA so that the power dissipation capabilities of the on-board chip is
not exceeded."
 
Need help to raise the output of the GTIL2 (lower my draw from the grid) around 200w more. (I'm in USA, 240v Split phase and know about the unbalanced load on the different phases. Didn't go with 1kw on each Leg due to wanting around 6KW or more I didn't want 6 units vs 3)

Currently I only have one inverter but I plan on adding another two shortly and for the most part I'm close to zero (I have 14.8k Enphase solar permitted and pushing back to the grid all day so back feed is not an issue) but always using around 200watt ish from the grid when solar is not producing.

I have a single (for now) GTIL2 200w and I have extended (Cat7 wire around 40-50ft) and installed 2 clamps in series (iotawatt ACCuCT 100A 50ma)

I originally had a pot trimmer (uxcell a14052600ux0954 10 Piece 10K Ohm 3296W 3 Pins Trim Pot Trimmer Potentiometer, 3296W-103) installed near the clamps but I found turned all the way it was still pulling from grid and the other way made it even worse so I removed it from the wiring.

So my question is if adding resistance to the line only makes it worse what can I do?

Also when I split the output to two inverters will this change anything?

Can I have it split to 3 inverters with one set of clamps? ( I think 3 if my goal right now) my electric hotwater heater and other big loads when on pull 5,500w
 
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I've read some things on German forums, but all are just about the 1000W GTIL2.
This one you can control with a small change to its controller PCB and then you just need external 0 to 5V and a resistor voltage divider.
That is the solution I'd like for the 2000W GTIL2, but it seems it only works with the 1000W version :(

For me this means right now: I have to buy the 1200W Soyo inverter and control it via RS485 :/
 
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