M-Functions

Task: Signal exchange between NC and PLC

A range of equipment, such as collet chucks, drill drives, transport equipment etc. is best not driven directly by the NC, but indirectly, using the PLC as an adapting and linking controller. This makes it easy to consider feedback or safety conditions, without having to adapt the NC program, or even the NC system. The NC’s M-functions involve digital signal exchange: functions are switched on or off, activated or deactivated. The transfer of numerical working parameters is not provided for here, but can be implemented in other ways (H-functions, T-numbers etc.).