Your comments

Thanks for the response, but I guess my question was unclear.

I'll try to clarify my point. 

I have a critical function that I would not like to be interrupted. I would like to make sure that in those conditions, the MC43 cannot be reprogrammed. This action could not even take place when the operator is directly connected to the unit. 

Is there a variable/parameter that we can use to limit the programmation of the unit?