CNC PLC Programming:
CNC PLC Controls TroubleshootingCNC PLC programming may be done within the CNC controller/CNC operator control panel or as in most cases there is a separate PLC for CNC machine. In the latter, maintenance would connect directly with the PLC and use that particular PLC vendor's software to access the CNC PLC programming.
This post and article referenced is about troubleshooting the CNC PLC control, and who can do what. Typically the CNC machine operator troubleshooting task is limited to responding to alarms on CNC control panel and visual inspections. Then if CNC operator can not resolve issue, maintenance is called and they will often use PLC ladder logic to speed more technical troubleshooting process as shown in the CNC PLC Control troubleshooting flowchart. The multi-meter is another supporting tool maintenance uses once the PLC ladder logic has quickly narrowed down the area of the system to test.
The PLC programming for CNC machine is commonly simple as the PLC typically only controls peripheral devices that support the CNC controller. Like this CNC PLC Control troubleshooting flowchart article example, the CNC door closed confirmation signal is detected by PLC and then communicated to CNC. The PLC may control and/or monitor other supporting device too like the coolant pump, the chip conveyor, indicator lights, air solenoid, etc. That article is a great example of use of PLC in CNC machines and sheds some additional light on difference between PLC and CNC machines.