Dead inverter? Clicking sound from inverter.

[al355]

Hi,

Have a 4kW setup which has worked well since being installed 2 years ago. Unfortunately at the weekend we heard a large clicking sound which turned out to be the inverter. Switching off half the panels via an isolator reduces the clicking and switching off the other half stops it. It sounds like a relay is clicking away. There is nothing on the LCD display on the inverter, no LEDs are on.

Other than test the voltage coming out of the panels is there anything else I could look at? Unfortunately the company that installed it were wound up a year ago

The inverter is a PowerOne 3.6 PVI

Thanks

[inetdog]

Welcome to Solar Panel Talk, al355! Sorry that your first post is under these circumstances.

I think that your inverter is dead and will need replacement or repair. Other than that, there is not much we can do in the way of remote diagnostics.
Measuring the panel voltage to make sure that Voc is not above the maximum input voltage spec for the inverter would be a good idea. Measure the current to see whether the inverter is presenting a near short circuit to the panels.
Beyond that, I have no suggestions.

[al355]

Thanks inetdog. Excuse my ignorance, what would cause the panels to give a higher voltage than they had been before? In terms of testing the panel output, is it a case of disconnecting from the inverter and using a multimeter? I appreciate that there's potentially large voltages so will do this when it's dark/cloudy.

[Sunking]

Thanks inetdog. Excuse my ignorance, what would cause the panels to give a higher voltage than they had been before?

No load on the panel from a dead inverter. .

Panels are current sources, not voltage. A panel without load will show Voc aka voltage open circuit. If you look at a panel spec it has two voltage rating Voc and Vmp aka voltage maximum power, Voc is always about 20% than vmp. So if you see voltages higher than Vmp means no current or power is flowing. Max Voc at cold temps must be lower than the inverter maximum input voltage.

To test all you have to do is read stickies like this one. .

[al355]

Thanks Sunking, I will read the sticky. The reason I think that there is output from the panels is the clicking sound from the inverter.

[Mike90250]

Power One, is a rebadged Xantrex GT Series inverter. They have a 5 year warranty. So possibly Schneider Electric can help.
Power one was bought out by ABB. I'd try them first, they bought the business, both good and bad half's of it. http://www.abb.com/solarinverters

[al355]

No load on the panel from a dead inverter. .

Panels are current sources, not voltage. A panel without load will show Voc aka voltage open circuit. If you look at a panel spec it has two voltage rating Voc and Vmp aka voltage maximum power, Voc is always about 20% than vmp. So if you see voltages higher than Vmp means no current or power is flowing. Max Voc at cold temps must be lower than the inverter maximum input voltage.

To test all you have to do is read stickies like this one. .

A couple of questions on this Sunking

1) You mention that only one panel should be tested at a time. I will see if this is possible for me without having to go on the roof but if I only want to test the voltage and not the current, shouldn't it be possible to do this in low sunlight with all 16 panels connected without a risk to safety? I assume that an installer would test all 16 panels together.

2) Judging by the specs for the inverter, the input should be around 300v (Voc) amd the load voltage 200v. Would you think that the inverter should switch on as soon as it gets the 200v with a minimum amount of power?

As a general point, other than the inverter, what could cause this type of failure? If a panel was to fail that wouldn't cause the whole system to fail would it?

Thanks

[al355]

Power One, is a rebadged Xantrex GT Series inverter. They have a 5 year warranty. So possibly Schneider Electric can help.
Power one was bought out by ABB. I'd try them first, they bought the business, both good and bad half's of it. http://www.abb.com/solarinverters

Thanks, I did call ABB but they weren't too great, said they need me to prove it's the inverter before they'll agree a replacement and even then I would need to find someone to do the replacement.

[Sunking]

A couple of questions on this Sunking

1) You mention that only one panel should be tested at a time.

You can test a whole string if you know what you are doing and understand the risk. With a grid tied string you can be working with say 2000 watt sting of panels with 500 volts @ 4 amps enough to kill dead right there on the spot.

[al355]

Tested the voltage (Voc) coming out of the panels and it was 295v. Called ABB this morning and they agreed to swap the inverter although I still need to find an installer to fit it.
Thanks for your help

[Oldoldoldman]

Hi, I want it if you get rid of it. tom

[al355]

44 days after reporting it to ABB, replacement arrived today from Italy. Installed in half an hour and back up and running

Think I will go for the extended 10 year warranty after this experience.