I am an engineering technician that has work on many robotic devices in my career. A friend of mine has 16 of these MAC301's that suffered from the premature reset problem. I proceeded to modify all 16 units. In the process I found one that has a burned up motor driver PCB and several others that of overheated boards and some with bulging filter caps. A spare unit also existed so I proceeded to reverse engineer the entire workings of this thing.
I found that the main power supply is set to 56 volts, but the marking for this power supply indicate it is a 48 volt power supply. The caps on the driver board are only rated for 63 volts and the clamping diodes are only rated for 60 volts! The clamping diodes appear to be what fails on this PCB's and some caps are bludging.
I suspect these power supplies are missadjusted and causes the driver to overheat and fail. Any thoughts? I have no service data.
