Mitsubishi Electric MELSEC iQ-R Series Configuration Manual page 75

I/O numbers of an empty slot
An empty slot is a slot where a module is not mounted, and occupies 16 points by default.
I/O numbers and the number of points can be set to empty slots for future use.
The number of I/O points can be changed for all empty slots at once by selecting the CPU module or remote head module on
2
the "Module Configuration" window as shown below.
2 ASSIGNMENT FOR MODULES
73
2.2 I/O Numbers of Modules