Tripower issues

[edexlab]

A Job I did last year which has been working flawlessly for 12mths has developed some problems and I'm a bit baffled to be honest!

There are 2 Tripowers a 1000TL and and a 15000tl Its developed over the last couple of weeks when the owner and the company I did it for reported various fault codes and occasional tripping of a 300mA RCD So I went to check, first I checked the events and there are numerous event logs of: Phase/Neutral conductor missing Grid overvoltage Grid undervoltage too fast Installation grid failure

Now it does seem fairly obvious there's a supply issue so I did all the basic electrical commissioning tests AC/DC no problem and the RCD tests fine The supply ZE/ PFC is slightly different to when it was tested but I expected this So next I then checked the tightness of every connection in the system and because its connected via a generator shutdown system I checked all the Contactors and Timers and its like it was installed yesterday I then rigged up 3 digital meters onto all phases (not having any other monitoring gear with me) and start the system up while I'm watching the voltages , everything is normal Generator relays working and no real fluctuation on each phase (I appreciate the three meters will vary but I'm just looking for a loss of a phase or an irratic voltage Next checked the events log and the events listed above are shown. to confirm the Neutral I did the same again with the meter on the neutral and a phase rotation tester on the phases just as an indicator to warns of a phase missing no issue except for the events codes as above

So to all intents the PV system and the electrical supply looks squeaky clean But I don't see how 2 inverters can both have exactly the same events precisely at the same time , the data has been forwarded to SMA as they don't think it can be a software issue. I've recommended having the supply monitored at various point throughout the system to try and pinpoint the problem I personally think there could be a supply issue occurring and perhaps some Harmonic issues but these haven't cropped up before so if anyone has had any similar issues I'd be very interested.

 

[edexlab]

apologies for the spacing of the above post I did space it to make it easier to read but for some reason it keeps coming up like it has

 

[Gavin A]

could be a fault at the suppliers end.

We had similar on a system which resulted in similar faults and it turned out to have been some builders in another house on the street had put a digger through the supply cable up the street, and the fault went away once the supply company came in and fixed it.

 

[Marvo]

apologies for the spacing of the above post I did space it to make it easier to read but for some reason it keeps coming up like it has

I paragraphed it for you.

There's a known issue with Internet explorer but if you click on the top left button of the reply box A/A and 'switch editor to source mode' it might work better.

 

[edexlab]

Thanks Marvo

 

[edexlab]

I am suspicious of the electrical system on this farm which we had little option but to connect to because there are numerous things there that I actually laughed at when the "maintenance electrician" told me they'd done , and these things were quite bad !

But as it hasn't had any problems so far it's possible its not a reason for these symptoms
There are sometimes problems with the supply but if the supply drops out the pv is disconnected to prevent damage to the backup generators