Fronius/Sanyo/SMA compatability problems?

[Energetic]

Does this issue occur on the SB 1200/1700/2500/3000 inverters or is it just a problem with the HF (and TL?) ranges?

I would be amazed if the SBXXXX series has a more sophisticated tracker than the HF range...

 

[Energetic]

So ... is this issue only present with somekind of partial moving shade on panels ??

Our experience is that this is hard shading such as a chimney in our case shading not more than a third of ONE panel but moving throughoutt the day causing the operation of the diode. The inverter 'sees' a step change in voltage as the diode reverse biases but to the human eye it looks like a very slow moving bit of shading...

 

[mdovey]

I would be amazed if the SBXXXX series has a more sophisticated tracker than the HF range...

Quite the opposite - it may be that the problem is because the tracker in the HF range is too sophisticated. I'm not an expert here, but I could quite see how a less sophisticated tracker might take a longer time to scan for peak movements, or is less precise in voltage measurements (and hence be looking at a broader voltage range for the peak), and the issue with Sanyo panels would not show up.

SMA tell me that the SB1200/1700/2500/3000 hardware is not compatible with optitrac so there will not be a firmware upgrade to support it (of course the firmware upgrade process on these inverters is more complicated than on the HF range).

 

[Energetic]

Quite the opposite - it may be that the problem is because the tracker in the HF range is too sophisticated. I'm not an expert here, but I could quite see how a less sophisticated tracker might take a longer time to scan for peak movements, or is less precise in voltage measurements (and hence be looking at a broader voltage range for the peak), and the issue with Sanyo panels would not show up.

SMA tell me that the SB1200/1700/2500/3000 hardware is not compatible with optitrac so there will not be a firmware upgrade to support it (of course the firmware upgrade process on these inverters is more complicated than on the HF range).

Hadn't considered that, quite possibly. One of the things we turned up it that the MPPT's SMA use were developed for wind turbines originally and then modified for solar, i guess it's possible that higher voltage fluctuations in turbines required a wider voltage scanning range which was trimmed for the HF range. I'm no expert either...

 

[ChasT]

I have a 3KW system which I have been having problems with since installation. Originally I had an SMA inverter but the problems were still the same.

The system works well in general but there are occasions when the system power will decrease over a period of time (30-45mins) in bright and sunny conditions. When I spot this occuring I have to shut the system down for a couple of minutes. When the system boots up again the output is good. The difference can be from 250w before shutdown to 2KW afterwards.

There is sometimes shading on the panels and I accept that there will be a drop in output because of shading but the shading is still in the same place after the system has booted up again so how can that be a problem, especially after only a couple of minutes?

I have contacted the installers who have been very helpful but I gather that Fronius and Sharp are not being very helpful. Whatever theories that people come up with all sound very reasonable until you add the arguement 'but why does the system suddenly work well after I turn it off and on again'.

Any help would be gratefully recieved.

I have pretty much the same problem. On a day of continuous, uninterrupted sunshine my Fronius will spend about 2 hours shutting down and will then suddenly reboot. The shutdown seems to start when the shadows reach a certain point but I haven't cracked what's the trigger for the reboot. Any passing cloud or turning off the panels will force a reboot. I got a smoke screen from Fronius, but I guess the mpp tracking software isn't up to the job.
If these things are liable to misfire in shaded conditions I feel we should have been warned. Were you? Let me know how you get one because I'm not too happy about being told that the only solution is to remove my chimney

ChaT

 

[Energetic]

Sounds like it's possible, what panels, how many and which fronius inverter?

 

[ChasT]

TL jnverter with 14 Sharpe 250s. Fronius' view is that the problem can only be fixed by removing the chimney.................
I still can't believe that a computer can spend 2.5 hours shutting itself down from 2.5 kw to 250 watt, without there being some check in the code to identify this.
ChasT

 

[Earthstore]

Change the inverter for an SMA and switch on the optitrac, that should cure your problem.

 

[Energetic]

Fronuis are developing their new range and so will not be doing any updates for the TL's. Optitrac may be the only way out of it. We managed to get fronius to take their inverter back so we could get an sma. PM me if you want details.