Sure it must be down to something I have done or haven't done lol but at the moment it's finding the time to sit down & work through problems. Machine works fine with the other plugin for cutting so there is no immediate rush. Think I will take your advice at some point though & start from scratch again, will reset the VFD to factory settings so I know where I am going & re enter all the values I need to change. Don't think it's an interference problem as the VFD must be communicating with the other plugin. Did originally use a bit of cy cable to connect but replaced that with a bit of shielded twisted pair after reading Jays comments.