Fanuc AC Servo Unit Maintenance Manual Fanuc AC Servo Unit Maintenance Manual. Covers maintenance of AC Servo Units with 1, 2 and 3 Axis driving the following motors: 1-Axis 2-Axis 3-Axis 5-0x 4-0x 3-0x 2-0xx 1-0xx 0xxx 5xxx 10xx 20Mx 20x 30x 30Rx Manufacturers: Fanuc Models: 1-0 10 2-0 20 20M 3-0 30 30R 4-0 5 5-0 Contents: Maintenance Manual