problematic inverter

solgen · Jul 29, 2011

Hi,

I've recently been informed by a customer that there PV system hasn't been coming on in the morning.

The system comprises 6 x 235 Sharp and Sunny Boy 1200.

It has been operational since December last year.

I visited the customer yesterday and it was sunny and sure enough the system wasn't active. The kWh meter was alive so into the loft where the inverter was and sure enough the inverter wasn't active. I switch DC off and and AC then reset and everything cam to life. This morning I had a phone call again and the same thing has happened. It appears that inverter now doesn't want to start up occasionally.

Has anyone had this happen do they know what the problem was? What did you do?

Appreciate some thoughts

PV Martin · Jul 29, 2011

its strange that the inverter was completely dead and not showing error messages, for it not to have livened up at all suggests that it was absent of either AC or DC? did you open the isolators and investigate for the presence of power? maybe a loose connection?? if that is not the issue i would suggest a faulty inverter.

when you say its not coming on in the morning, does this mean it comes on later or not at all?

solgen · Jul 29, 2011

Hi, I've only just been made aware of this problem occuring so will investigate more fully next time if and when it happens again.

At the moment I can only definately say a start-up problem has occurred this morning and that by switching everything off and back on again has forced it into life.

The performance history shows that in June it had not worked for 3 days before coming back to life. This maybe a Red herring so I can only start to debug from this point onwards, so I will be measuring Voc and Isc etc.

My intial thoughts were that the temperature of the loft space was causing a shutdown. However, in the morning when it has been bright and the loft space quite cool it still hasn't come on.

Could it be that it has been too hot, the inverter switches itself off and then latches off until a re-boot?

If the inverter has gone faulty and I'm able to swap under guarantee then fine, however, I want to know why a fault has developed because if it's something to do with temperature the fault may develop again.

Thanks