Hey,
I bought 2 mppts 100/20 and they are running in an ESS System. The PV Panels are directed nearly in the same direction, but sometimes they reduce the output to 0W for a while... (Left image at around 13:30). Second mppt on the right working without problem at this time.
I don't get any errors anywhere and the battery voltage seems to be good, so I don't get why this is happening. Both mppts are doning this, but not at the same time, and only about 2 times a week for about 30-60mins.
Thanks for any hint.