Sunnyboy failure

[TPES]

Don't really have any experience in PV and very keen to learn all I can, today in a loft I saw the inverter with the failure light blinking, the home owner says they don't think it's working...

Any advice on the next steps to take?

 

[TPES]

I didn't investigate it too much while I was there as it wasn't the reason I was originally called out, but I know there was no AC voltage. So I guess it's either the panels or the inverter

 

[Worcester]

Why would you want to fix someone else's install? (Apart form good customer service, or they'r paying you)

If your customer really values you, why not be present when they call the installer out to fix it? If it was my customer and I had a long standing relationship with them that's what I would do. (even though we could almost certainly find what the problem is ourselves)

Sorry without details of the installation, little anybody here can do to help you.

 

[yellowvanman]

No AC voltage then MCB or RCD tripped? Inverter needs ac to start ie. it doesn't just generate ac it needs to see the grid voltage before it can work.

 

[TPES]

Ok, It was originally installed about 6 years ago. The MCB is on (not RCD protected). Im just trying to find the fault for my own personal benefit/experience. House is empty for me to work. I'm there doing PIR remedial work

 

[SolarCity]

First thing to do is check the AC supply. If you have no juice then, as had already been mentioned, the inverter will not operate. If that is the case then it should be pretty straight-forward to work out.

 

[Worcester]

BiggsSolar has exceeded their stored private messages quota and cannot accept further messages until they clear some space.

Tried to PM you!

 

[SolarCity]

Sorry Gordon, cleared now

 

[Worcester]

@TPES Heres a quick overview, I'm assumimg you're a qualified sparks and will take the correct protective precautions..

Check the AC side and that there is power to the inverter, then switch it off (isolator Switch)

If there is no AC power to the inverter it will not work and will display a fault mesage. It has to be connected to the grid as the inverter monitors that and synchronises itself to it.

If you have AC power to the inverter, then check the DC side (be careful all the DC system is live)

Turn of the DC isolator, disconnect the two dc plugs from the inverter, and you want to do two tests, one Voc - the Open Circuit Voltage, so with a proper DC test meter connect it up to the two dc plugs (we have test leads with the proper plugs on) then close the DC breaker and as a quick guess (all dependant upon the module types and amount of sun) you should typically see a DC open circuit volt reading in the region of 40v x the # of panels (they are connected in series like a battery in a torch)

The second test to do is to open the DC Isolator, connect the 2 DC plugs together and using a DC Clamp meter, measure the Short Circuit Current (Isc) with the plugs connected and the ammeter in place close the DC isolator take the reading, open the isolator. You will get a current reading that is most dependant upon the amount of sun and the angle of the panels, it could be anything from 0 Amps at night to 6+amps in full sunlight.

If you've got voltage and current.

Put the DC plugs back on the inverter, close the DC Isolator, watch all the information that comes up on the inverter, Close the AC isolator.

It'll take about three minutes to synchronise with the grid before it starts generating.

You can download the Sunny Boy manual from the SMA Website Home. SMA Solar Technology AG which will give you the fault codes

 

[TPES]

Thanks Worcester. Appreciate that. Good reply.