FB -thanks for the offer. I nearly called on you because I thought I wasn't going to be here this morning, and my wife was going to have to deal with everything, but my plans changed at the last minute!
Was a bit surprised when the same electrician turned up today to fix the problems... He looked a little sheepish, but went with the 'I heard you're having a few problems' line when he arrived. I explained all the concerns, and he said he was sure it was no problem and he could fix them. He went into the loft to look at the inverter, and took about ten minutes before coming down again and saying there had been 'connector in the inverter which should have been connected in the factory but hadn't', which had meant the first string hadn't been working. He was at least prepared to accept that it wasn't the easiest to check and commission the panels originally (ie. when it was DARK!).
He then took the import meter and tails apart, and replaced the chewed cables. It's no great surprise that the new cables appear to have the grey additional insulation on! I did manage to get a quick look at the tails he took off, and although it's a rubbish photo, sure enough there was a lot more damage under the sticky tape:
View attachment 17141
As soon as he'd finished, the output was pretty much transformed - it was a relatively sunny morning, and the panels were putting out 2kw straight away - far in excess of anything we've achieved so far.
He said that the garage and two of the panels from the roof are on one string, and the other eight are on the other.
Sadly, later in the morning the serial cable was knocked out of the monitoring PC and I didn't notice, therefore we don't have a full day of data, so I'm hoping for sunshine tomorrow! Once I have a few days in the bank, I can compare with FB and see how we're getting on
On the whole he was pleasant and polite, but wholly unapologetic. He did leave with a 'if you have any other problems then don't hesitate to call the office'! I imagine it's fairly obvious by now that I won't hesitate to do that!
So I think I have a correctly set-up and safe system working now. Thinking on whether to take the advice of some here and report them in any case due to the shoddy workmanship the first time around.