The 6.3 A fuse at position F902 on the MAC 2000 Performance power supply has proven to be slightly under-dimensioned for operation at 120 V / 60 Hz. Under these conditions, this fuse has a tendency to blow during software upload, resulting in failure of the 30 V output and loss of motor function. This can be confirmed easily by removing the base cover over the PCB and checking the status of the "+30V" LED: if it does not light, the fuse is most likely blown.
To solve this problem we changed to a 10 A time-delay fuse, P/N 05020025, "Fuse 10AT". starting with S/N 4239590001.
All products with lower serial numbers have the 6.3 A fuse. We recommend changing to the 10 A fuse if operating at 120 V. The fuse is accessed by isolating the fixture from power and opening the aluminum base side cover closest to the control panel.