Insulating Timber Garage

[nowty]

Seeing 249vac on terminals of inverter.
Maybe too high

249V is still within grid spec.

Do you know the Vmax of the panels ?, and as they are second hand they might be down a volt or two. Its also an alleged heatwave, so panel voltage suffers in hot conditions. And being an almost flat roof your not going to get max power voltage out of them either.

You might find it starts up in the cooler morning.

[AGT]

I was getting 270 volts DC about an hour ago can’t find panel photo at the moment.

It’s only 15 deg c here

[nowty]

I was getting 270 volts DC about an hour ago can’t find panel photo at the moment.

It’s only 15 deg c here

OK thats very late in the day, extreme poor sun angle and 270V is likely to be open circuit voltage so Vmax power voltage likely only to be 220V 'ish.

Hopefully the voltage will be better tomorrow when the sun is higher.

EDIT - My original 250W panels run at 220V in a string of 8, so if I had 9 they would run at 247V which would barely be enough for your grid voltage and that old inverter.

[AGT]

Inverter data plate

[nowty]

The manual also says it has a default start up voltage of 300V so if it has not been already set to the minimum start up voltage of 250V it also may not start up because of that. That will be the open circuit voltage.

Page 77 of the manual.
https://files.sma.de/downloads/SB2500-11-EE4801.pdf

So thats 2 problems you may be up against.

[AGT]

As always cheers for your time and advise!
Didn’t see that in the manual, just saw the minimum level on the data plate( inverter was second hand too)

Will see if I get home while there is some decent sunshine to see any start up.

With the sunny boy not having any buttons to press,scroll,accept, assume you need a software package to alter installer settings?

[nowty]

As always cheers for your time and advise!
Didn’t see that in the manual, just saw the minimum level on the data plate( inverter was second hand too)

Will see if I get home while there is some decent sunshine to see any start up.

With the sunny boy not having any buttons to press,scroll,accept, assume you need a software package to alter installer settings?

You can only scroll through the display by physically knocking on the display. I had a Sunny Boy 1200 which is a slightly later model that accepted a bluetooth piggyback card inside so I could change the settings with a bluetooth laptop running Sunny Explorer.

But I suspect yours might only be possible installing an RS232 or RS485 board in the unit but It may have one already. Info is in that manual I linked.

Do you actually have a manual for it when you bought it ?, I'm only going off what I found online and there have been several updates for those inverters. But the writing "Sunny Boy" on the front with that blue writing makes me think its an older version. But the info plate does say refurbished so maybe the innards are newer.

[AGT]

No manual, just an ‘assurance’ was working fine.

Didn’t know it was a refurbished unit, currently in garage and switched everything back on, it’s over cast and rainy and panels are producing 287volts.

Unfortunately will have to leave soon before it gets to the 300,



Unit has 5999 hrs on it and 2274 kWh so not worked hard!

[AGT]

Found PV spec

[nowty]

Found PV spec

Theoretically they should just about work.

But I just checked one of my spare 14 year old 250W Suntech panels with practically the same spec.

In full sun the Voc is 35V and 33V in the shade.

The ones on the roof in full sun are only operating (Vmpp) at 26.25V each but it is like 25 degrees here with the panel temps around 50 degrees.

When you get back let us know what the LEDs are doing.

Info on them here,
https://www.solargain.com.au/sites/defa ... Manual.pdf