Have had Sunny Boy 4000TL installed for six years with absolutely no problems .. until the last few very hot days. Output cuts out for periods of about 20 minutes (then comes on again) from about 11 am to 2 pm (peak time). Inverter is in attic - gets hot! I've monitored closely and by opening access door and getting a breeze through attic it seems to be able to cope. Today I've helped it with a subsidiary fan and all seems well, even though it's hot and still outside. There is a fan installed in the inverter but I wonder if it, or its controller, has partly failed. I seem to think, in the past, I've heard quite a bit of noise from the fan as it worked hard. Now it is still making a small sound but not blowing very hard. I know it's a 12v DC fan but is it supposed to come on gradually or should it be 'all or nothing' if the temperature sensor calls for it come on? I've checked for cobwebs etc - nothing. Youtube videos show cleaning etc, but, understandably nothing more. Are we the only ones with problems?
Inverter cutting out in hot weather
- Thread starter nr16apple
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would you work very well if you were stuck in a hot loft? no? well your inverter feels the same
now you know why I don't fit inverters in attics unles they are well ventilated, or I have no choice. SMAs work upto 70 0C, beyond that they shut down for self preservation. They will derate themselves as well to become less efficient as another mode of protection, but there is still a limit with regards to the upper temperature they can sustain. I would suggest looking at potential locations to relocate the inverter to, such as an outside wall, or consider having a few roof vents fitted. A cooler location would be my choice, as this will extend it's overall lifespan.
its easy....
Thanks for all responses. As I said it's not been an issue before in 6 years, and we certainly have had an incredibly long spell of very hot weather, so hopefully it will not be a regular issue, but looks like arranging for some extra ventilation, at least, would be a good move.
Just leave the loft hatch open on these rare occasions the UK has a long hot spell!
This string got me concerned about my invertor, cooking away whilst pushing out about 2.5kW most afternoons. It now has a temporary cooling fan to help. It's just on a timeswitch for about 10-30am until 6.30pm. Can't do any harm.
Update! Now that the really hot weather has ended and even though I've improved the ventilation and I am still powering the integral cooling fan from a separate source, it still cuts out occasionally. It's quite happy generating 2.5 to 3 kw in the morning (we face quite a bit east of south), but from about noon on sunny days it begins a cycle of (more or less) one hour on then half an hour off. So today, for example, total generated was 14.9kwh and I reckon if I fill in the gaps on the Sunny Beam display it would total about 17kwh. So my conclusion is that the overheating in July (and even more in early August) has damaged something making it more sensitive. Does anyone test and repair Sunny Boy inverters or is it a case of hang on until I decide I'm losing too much (or it gets progressively worse?) and dump it in favour of a new one?
might be worth contacting SMA technical help - don't be put off by the German phone number, they speak very good technical English, and they usually have an English fella answer the uk calls anyway. Also worth checkin the disaply for the grid voltage, last time I had a scenario whereby the system was shutting down around mid-day it was due the grid voltage being high and not allowing the inverter to export energy.
I have my system in the loft put in by a company, battery failed and sp controller before I really realised what your all saying. So my solution to my issue was I have a goid fan in the area of the equipment and proper ventalation to allow the air to flow outside. It was not my choice to put it in the loft as I had a company install it. I would never install in a loft again.
most companies shoved all the equipmnt in the loft because it's easier. In theory it shouldn't make much difference because the inverter will protect itself by effectively shutting down in stages, but, hot electrics don't last as long or work as efficiently, so you lose output from the system when it should be flying along. Batteries don't like temperature extremes either.
If you live in a bungalow like mine there isn't much choice. You don't really want a damn great big blue box on the living room wall and the garage is detached.
most inverters are IP65 rated, so can be mounted on an external wall, ideally a shady wall and not in the full sun. That generally means an end wall where you don't see the box. It's partly depenedent on the roof size and the panel array. If your array virtually cvers the entire roof, then it shades the roof anyway, and temperatures don't get so high in the loft. It also depends on how well the loft space is ventilated, some seem to have a howling gale blowing through them, others have virtually no air movement at all. Only way to check is stick your head in the loft on a hot sunny day. My own inverter is on an external garage wall, in full sun and does get upto 700C in the summer. But my inverter is an older model that is less efficient, so generates more internal heat. I have rebuilt the garage roof this year and given it total shade, so it will be interesting how that affects it.
