Hi,

Does anyone know why this is happening? I cant see any trees etc which might be shading the panels. Please see pic

Regards

1 hour ago, Slarty said:

Does anyone know why this is happening? I cant see any trees etc which might be shading the panels. Please see pic

batteries full and nowhere else to with the power that could be produced, maybe?

Perhaps some more details would help like how big is the inverter and what specs and settings for SOC etc are you running? Also is this constantly the case?

@Kalahari Meerkat I don't think it is a case of battery full if you look at the production after the gap at 12:00 it resumes again. I think he is referring to that 12:00 sudden dip.

Is there any fault codes on the inverter perhaps? What I'm looking at is that 5k+ spike at 12:00 and wondering if something isn't tripping the inverter or something but again hard to determine without knowing a tad bit more. I take it there was no clouds either that could have caused the sudden drop?

I have 2 inverters both 5kW so 10kW in total. The settings are:

Zero export to CT

Load first

TOU settings:-

00.00 to 05.00 60%.

05.00 to 00.00 40%

2 hours ago, -cK- said:

What I'm looking at is that 5k+ spike at 12:00 and wondering if something isn't tripping the inverter

If the inverter was tripping, you'd expect the load should also be interrupted, but it just keeps operating. One would also maybe notice if the power goes off.

@Slarty can you see if the load is just being transferred to grid or battery during that time?

What panels do you have, how are they connected, and can you show the PV1 and PV2 Voltage during that PV outage, for both inverters?

Nothing is tripping the inverters. If the batteries are full at this time, I would have thought there would be a sharp cut-off as per the photo and remain down but then it zooms back up again! I will look more closely tommorow at midday. Thanks for your help

Maybe the inverter is throttling the PV because it exceeds the MPPT rating? Then after midday when the angle isn’t perfect it resumes again?

@Slarty do you have a "PV diverting" device installed in your setup? Something what is able to heat the water in geyser for example, based on the excess PV generation?

2 hours ago, Denns said:

Maybe the inverter is throttling the PV because it exceeds the MPPT rating? Then after midday when the angle isn’t perfect it resumes again?

Based on the short period with a very small difference in angle I doubt that it will cause such a big drop. Also as said why does the generation pick up so much with not a increased load to cause it.

7 hours ago, Scorp007 said:

Based on the short period with a very small difference in angle I doubt that it will cause such a big drop. Also as said why does the generation pick up so much with not an increased load to cause it.

Fair point. Maybe there isn’t anything wrong and it’s just an issue with the data logger. Mine creates gaps if the network drops.

1 hour ago, Denns said:

Fair point. Maybe there isn’t anything wrong and it’s just an issue with the data logger. Mine creates gaps if the network drops.

I have had long drops lasting many hours where the logger would not connect to the WiFi if the WiFi is on a cell phone hot point. Tried it out for days and then moved the connection back to a normal router and no problems after the move. The key point is that via hot spots loggers can create a lot of unexplained problems when it comes to connections.

12 hours ago, GreenFields said:

If the inverter was tripping, you'd expect the load should also be interrupted, but it just keeps operating. One would also maybe notice if the power goes off.

@Slarty can you see if the load is just being transferred to grid or battery during that time?

What panels do you have, how are they connected, and can you show the PV1 and PV2 Voltage during that PV outage, for both inverters?

Not necessarily, I had this happen when people didn't check the active loads and accidentally tried pulling 8-9kw load on a 5kw inverter and it just threw me to grid power and tripped the inverter alarm with an over current fault. I only noticed it as I was at my pc and heard the ups of the pc actually flipping its relay. Not sure if I had to manually intervene by restarting the inverter or whether the inverter just cleared itself after a while once I brought the power draw back down.

But given this is 2x 5kw inverters I doubt that is the case.

On the suggested data logger issue would it not also have gaps in the consumption graph if it drops off network or have you all had intermittent data drops like just one bit of the stream and the rest records fine?

There's a sharp increase in the demand for power just before PV consumption drops off. Coincidental? Check the other logs available to you. See if there is an error message that corresponds with the time of that spike.

As a general rule these devices must balance grid, PV and battery. It would give you a fuller picture if you can see what is being drawn from grid and battery at the same time that spike happens and PV drops off.

Do you think it could be a software bug so it just stops for some reason.