Ok this is in dealing with a neff press machine. the company installed lasers on it in order to make sure that a particular operation was done before press. once the laser see that the part has been grounded, it allows the operator to start the press process, the problem i was running into is that the machine runs other parts as well so the logic i put in the machine for the part number needed to be able to turned on, only when operating that specific part number. So thats why i was asking the question of trying to store two programs on one PLC. The Answer was tracing the digital input back through to panel view and finding out what the part selection was using when it pulled up in the PLC, since the panelview and PLC are linked. I found out the Integer number and address it was using and inserted a EQU & NEQ instruction and that allowed selection from back and forward between different part numbers.