“X” typically indicates a relay coil. “O” indicates a contact (normally open or normally closed). The full diagram has a legend on page 1.

The MK5 wiring diagram is . You need your compressor’s serial number (on nameplate). Then:

Details the high-voltage supply, motor data (e.g., kW, HP, SF), and fuse settings. Regulator Mk5 (Graphic & Touch):

Proper setup requires strict adherence to safety and environmental standards: