To my delight, I have been given a shot at designing a solar tracking system, the arrays running at 24V. The arrays are very large, 14' sq and 18' sq. The user is UNCONNECTED from the AC mains, running his entire business from inverters attached to the system. Anybody have ideas? I know about (1) not allowing the moon to be tracked, (2) end the day by moving the array to immediately catch the dawn sun when it comes up, to minimize movement, and (3) the funny 4-diode array to determine where the sun is.. --Bob -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist