Screw air compressor line assembly : sort the wiring harness according to the circuit diagram, distinguish the power line and the control line, and use the line number tube to mark the corresponding interface to avoid misconnection ; then the power line is connected to the frequency converter, the stripping length is strictly controlled, the copper core is completely inserted into the terminal, and the wire clamp is compacted. After each wiring, insulation inspection is performed, and the control line avoids the power line to reduce interference ; finally, the wiring harness is arranged and fixed in an orderly manner with a strap to ensure that the wiring in the cabinet is neat and tidy, which is convenient for subsequent maintenance.