IstaBreeze® i-500 wind generator in 12V - Test with battery and Charge Controller

Got this very rude comment from Fast Trading LTD:
"Have you ever worked with windmills before? I think it makes sense that you speak to our technician I gave the phone number.
everything seems ok i checked the videos you have 6 volts on 2 phases that's almost 12 volts on 3 phases at this speed and you need at least 900 rpm to get good performance.
My tip: just install it. You can't test with a fan. Recommend WIND TUNNEL
Erkan Urut"

[@FrancisdeBriey]

Volts alone have no meaning, you need to measure Watts =Volts x Amperes when the wind turbine charges an almost empty battery through a charge controller

[@StellanLarsson]

Thanks have been doing it now for a few months. Absolute peak during a storm was 136 watts. Windy day around 15 watts. I use a "Vicron" MPPT to measure with. The battery does not get full, the small consumption that the Vicron has is more than what I get from the generator over time.