Two of these came with my Outback Flexpower system. It's only been 2 months but they're performing well. Have had a couple brief power spikes of 4200 watts from the array into one of them, handled it fine (4000W max. recommended).
Also make sure when you size your strings you stay well below the 150V threshold--apparently they can be damaged irreparably if you go above that. Factor in coldest possible temps. in your location when you run the numbers, as open circuit voltage on panels can increase significantly. I'm using strings of 3 panels rated at 40VOC and it's been fine--highest voltage has been 122 even on bitter cold mornings.
Know that the fans are loud--am glad these are mounted in an outbuilding, not the house. Fan rarely runs, just briefly on and off around solar noon on a sunny day. But come summer, when temps warm up, I expect the fan will run much more frequently. Just don't let that surprise you.
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