A.1. Differences and similarities
Taking the other model of PLC controller from CPM1A class basically doesn’t change a thing! Everything said for one model also applies to the other. Only thing that changes is the number of screw terminal and the number of bits in IR area connected to that screw terminal. If model with 10 I/O lines (model described in the book) has 6 inputs on addresses IR0000 - IR0005, then the 20 I/O lines model will have 12 inputs on addresses IR0000 - IR0011. Expanding itself should not be a problem. After taking off the cover on the right side, there is a connector which is then connected to the expansion module via flat cable. Still, it requires skill when assigning inputs and outputs because expansion increases the cost of the project. All the models and expansions of CPM1A class carry additional marks defining them more precisely.
Notice that PLC controllers with 10 and 20 I/O lines do not have an expansion port. Generally speaking, if there is the slightest possibility for expansion in the project, PLC controller with 30 or 40 I/O lines should be used.
Notice that PLC controllers with 10 and 20 I/O lines do not have an expansion port. Generally speaking, if there is the slightest possibility for expansion in the project, PLC controller with 30 or 40 I/O lines should be used.