Generation Loss and Surge on a cloudless sunny day ?

[Hydroteam]

Hi,

I have posted here a graph of the last two days of generation from my PV system.

Both days pretty well the same, with sunshine throughout.

I had a "funny" yesterday between 9 and 10 in the morning, an apparent loss of power and then a surge. Nothing to explain it, no clouds in the sky, no shadow issues and no error messages on the inverter logs.

The data is from the SMA sunnybeam monitor, but looking at the Inverter data through Sunny Explorer shows an identical profile so it is "genuine" inverter data.

I noticed a similar occurrence a few days after installation in November but put it down to a "settling down period glitch" and thought nothing of it.

I can only assume it is an anomaly caused in the inverter rather than the generation from the panels themselves.

Does anyone have any suggestions as to the cause and is it something I should be concerned about?

Thanks...

[ovonrein]

This looks like a "bucketing" error, no more.  Could be the charting s/w, although you say that it happens with Beam and Explorer (which are unlikely to share one charting engine).  So might be a glitch in the data gatherer on the inverter itself.  Which inverter is this?  Did the chart originate from data Exported from Explorer or from data imported from Beam?

[Hydroteam]

Hi Ovonrein,

Thanks for response, I tend to agree with you and hope it is a data anomaly rather than what is actually happening in the inverter.

The data in the graph originates from the sunnybeam csv files, but I also see the same data profile when "communicating" with the inverter through the SMA sunny explorer program, which implies to me that this is "valid" data logged in the inverter.

The inverter is a SMA 4000TL

[ovonrein]

I have the same inverter but have never seen this before (mind, my system's only 3 month old).  How old is your inverter?  Might it benefit from a f/w upgrade?

[Hydroteam]

3 months also, installation was early November - can we, as users, do the firmware upgrade or does that need an installer password?

[ovonrein]

We are supposed to be able to do it ourselves.  Check (via Sunny Explorer) which f/w version is installed on inverter, and then check on SMA web site whether there is a newer version.  Then check change logs whether there is any mention about any changes to the data logging between your version and theirs.  If not, drop an email to SMA and ask about this weird phenomenon.

[Lurk]

I think I have an issue - my inverter has just thrown a wobbler-  second decent day of sunshine this year and it 'trips' recording as 'grid' problem.... Ive powered down and reset its fired up fine. Now I have a smaller system on the same supply and no fault - so am stumped - will monitor over the next few weeks to see what happens. Blooming typical having just set the washing machine going and then finding out half the power that should be there isn't ! Cloudless sky and just above freezing having warmed up from 8 below freezing at 9am. Its now putting out 1,014w from 10 of 220w panels so hard to think it got a surge from the panels ?
Any ideas ?

[Hydroteam]

I have seen quite a few threads on inverters tripping and they all seem to point to either:

- use of 30A wiring as opposed to 100A wiring or something along those lines

or

- incorrect UK setting of the inverter

What inverter do you have?

[Lurk]

Inverter on my 'suspect system is a SB 2000HF-30
lurk

[marshman]

Inverter on my 'suspect system is a SB 2000HF-30
lurk

Two things to check:

1. Make sure the inverter is set to UK G83/1

2. If you have access to the inverter log files - I'm not familiar with your inverter - but on my SB3000 I can see the grid voltage and see what it gets up to. Mine regularly trips in the summer months displaying grid xxxxxx   and its caused by the grid volts going too high. I would be suprised if this was the problem at this time of year but if you are in a rural area and because you have two systems on the same feed this may cause the inverter to trip. The fact you other system doesn't could be due to several factors - one of which may be a slightly shorter AC cable run so less volts drop. But I think the key is to look and see what the actual error is.

Roger

[Lurk]

When it fires up it appears to be set up for UK - I will check again - can this be done through SB explorer ? while the system is running or is only on the inverter start up screen ?
How would I enter get access to the log files - or are you referring to the output files via SB explorer

yep very rural area - the smaller system is on a 60mtr run via 240v 32amp spur to the workshop CU. The main system is on a 6 meter cable run direct into the main house CU and in-comming 240v supply. Iwill be checking the logged output a bit more carefully - having said that only the main system is on the Explorer so maybe the smaller system reset itself quicker than the larger ?

lurk

[Iain]

Hi
I had issues a while back with the inverter tripping out about 6 times in a day. I phoned up the power company and found out they were doing line switching that day causing spikes. Worth giving them a call to see if any work is being carried out in the area or if there are any large load /generators in the area that could cause fluctuations.. Mine has been OK since that day.
Iain