Good question, looks like @Bud Martin is having the same issue, my Growatt has a 240v 75lbs transformer so without an Oscilloscope or others suggestions, I could not tell you. Mabe someone else can chime in.We have been checking and rechecking all of the wiring for a couple of weeks to ensure that it is not something we did. Battery voltages are stable with sun at the float when charged. After sundown it stays stable at 26.5V under no load. When both fridges are running the voltage drops to 26.2V then rebounds back to 26.5V after they shut down. I usually have 26.2V at sun up. I have checked these voltages everyday and have multimeters laying at both fridge outlets. I also have Kill-A Watts plugged in to observe the fridge outlets.
We have checked voltages at every connection leaving the Growatt to the disconnect, to the breakers, at the outlets. When the fridges run together, the voltages fluctuate and the Kill-A-Watts show the frequency bouncing around a little. But when the fridges are not running, all is stable. I have test the inverter under heavy loads with two heat guns pulling to capacity, and the voltages are stable. It is only when two fridge compressors are running.
Could they be feeding noise back and causing this?
The flickering was there from day one, but I never really noticed as I wasn't looking for it. The flickering starts out very softly, then gets more intense as the compressors run longer. It only happens when both are running at the same time, and you have to open the fridge at that exact time. Once I realized this could be a problem, I started looking for it, and opened the fridge every time I heard the compressor run, then you start seeing it more often and watching it longer to see it intensify. We have been looking for the problem for weeks now."I have a Growatt 3000 LVM 24V inverter. I have been so happy with it until recently." So the problem just started? It was running with the two fridge in the past with the same exact setup fine without any flickering until now?
That would be easier, but the idea is to have four very important things running in the event of an outage. We have frequent outages, and in winter they are quite long sometimes. We are often gone on weekends during the summer. So we need to have the following running when we are not home, and an outage occurs. We do not want a flooded basement, and spoiled food.I am wondering if it wouldn't be easier to just only run one fridge off the Growatt. Move the most efficient unit back to grid?
That would be easier, but the idea is to have four very important things running in the event of an outage. We have frequent outages, and in winter they are quite long sometimes. We are often gone on weekends during the summer. So we need to have the following running when we are not home, and an outage occurs. We do not want a flooded basement, and spoiled food.
2 fridge/freezers
1 upright freezer when being used
2 sump pumps
We have other things running on the solar which is a bonus, along with a smaller electric bill. We had plans to add an additional Growatt to cover our furnace in the winter. That is now out for me.
This is very likely nothing to do with the rods in the ground.
Its very likely about having multiple bonds between neutral and ground.
You can isolate your panels for a test.
I guess I'll just move along.
I looked at #24, and it is only available when connecting Growatt's in parallel (expansion). I am not sure that any parameters above #22 can be accessed. Thanks!@Repro...I just saw this thread. Having a similar issue...
- I have the Growatt 3000TL-LVM-48P
- Among other loads, I had it running a full size Whirlpool side-by-side fridge on a dedicated 20A circuit. I thought it was running fine for several days, but one day wife said lights inside were flickering on both sides (fridge/freezer).
At the moment the system is disconnected. I was planning to troubleshoot the issue in the coming days. I put the fridge back on its original utility grid circuit in the meantime. Working fine.
Like @smoothJoey was mentioning (on the first page of this thread), I was skeptical the earth ground thing would solve the problem. I think he was onto something where he mentioned the neutral-ground bond causing ground loops.
As I understand it, the Growatt will unbond neutral and ground when powered by AC input, but will automatically bond ground-neutral when running from battery/solar, after the ATS makes the transfer. Could that be creating a problematic ground loop? This would explain why a different inverter you hooked up does not cause the same issue as the Growatt? Can the Growatt be set to NOT do its N-G bond thing? I believe there may be a setting for this (#24 possibly?).
It seems SJ left the thread, but maybe he will come back to offer ideas.
I don't know what you mean by Tier 1? I know what Tier 1 solar panels are, but that will not help me. Can you elaborate please?Here is my suggestion as I am in a similar situation with wanting the freezers protected in case of outages. Move the GroWatt to the furnace. Buy a Tier 1 unit to user on the freezers, etc. Samlex or Victron. Others are better at knowing the Tier one units. I need to do this as well - then the GroWatt becomes the backup. One is none, two is one.