Do Check That Inverter Is Working!

Jane had to take Lala to be put down shortly before Xmas. We were very sad to lose her – I probably spent more time in her company than anyone else’s over the last year – but she was suffering brief periods of what looked like great discomfort and it was time to say goodbye. She spend much of her last few days trying to get comfy on a chair, she couldn’t curl up any more, or toasting herself by the gas fire 🙁

Lala Chair Dec 2012Anyway I decided to put her big, pink, covered, litter tray up in the attic which was my first trip up there for many a month. While I was there I decided to take a look at our solar inverters and saw the red fault light was displaying on one. I’d like to say I was surprised but to be honest I’d been suspicious of our low generation readings for a couple of months and had just been too lazy to check. It has been such a miserable summer of rain, rain and rain that I hadn’t been that surprised to see our readings drop – all the same I’d been justifying poor readings to myself by thinking that despite the sun being out for a change it was at the wrong angle for the arrays and that sort of thing. I do have a power monitor rigged up to the solar AC output via a current transformer so can tell roughly what it’s generating at any particular time.

The inverters have a 10 year guarantee so I emailed Solar PVE who got right back with the suggestion I try power cycling the system. It’s important to turn it all off in the right order, AC isolator first then the DC isolators. I was also asked to give it 10 minutes for the capacitors to discharge before restarting. The fault light was still on after this so, this being just before Xmas, Solar PVE offered either to get someone out after the holidays or, if I felt I could install it myself, they could send me a replacement next day delivery. I went and had a quick look, 4 mounting screws and 3 plug-in connectors, and said I’d do it myself.

InvertersGood to their word a new inverter was sent by fast courier and it took me less than 30 minutes to install – plus the same again to negotiate the unreadable Japanese menus using the manual to set the menu and read-out language to English. The AC output was noticeably higher straight away despite it being a cloudy December day and at midday the first sunny day I saw it was generating 1500W for the first time in ages. I was left kicking myself for not checking and dealing with it earlier.

So the total generation for 2012 was down to 1548 kWh compared to about 2230 kWh for 2011, much of this down to the most wet and dismal year on record but I suspect a couple of hundred kilo-Watt hours lost due to me being too lazy to check the inverters when I first suspected a problem back in September. On the bright side the amount of electric we consumed from the grid was 1311 kWh (this obviously doesn’t include energy we’ve generated and used directly) so we are still generating much more than we are buying.