I have a pair of ST-2500s running from identical 16 module KC-120 pannels and the units also exibit the same startup problems. The West unit start a good hour after the East one, and produces about 10% less each day. While in its early morning thinking mode, it cycles the fan on for 30 seconds then off for 20 seconds and does this for an hour. Finnaly it starts and produces at approximately the same level as its East twin. Complaints to Xantrex get a technican who listens politely, but offers no solutions. Each unit has the current firmware load. The West unit also exibited another unusual characteristic this summer in that it would produce a high pitch squeal for 20 seconds out of every minute, going for hours at a time. The unit is in the shade on 100+ F days. Same technical advised that when it quit producing, I should let them know and if it was still under warranty, they would fix it. It's still running,so I guess the neighbors will just have to suffer. Squeal goes away when the days get cooler. Anybody else have this problem?

Hi Alan,

This is not normal, the only audible noise should be the fan. Any electronics switching noise or inductor noise should be negligible. We would like to service the units you have any problems with for a free upgrade in December. Please sit tight until then, as we have some details to work out on our end first. We will take 100% care of any units you have any problems with. Please visit our website at www.xantrex.com for more information.

Thank you. Tobin Booth, Xantrex Technology