Please look the diagram in the link.
This is the output expansion module connections for S7-200 series.
I have two doubts. For the 24 VDC output module, unlike relay output module, why do you need to connect the return of the supply to the CPU, as the function of the PLC is to merely to switch between output terminal and the common?
Another doubt is, for the 120/230 AC output module, what does the broken line connection indicate? Why there are two identical terminals 0L?
Hope anyone oblige.
This is the output expansion module connections for S7-200 series.
I have two doubts. For the 24 VDC output module, unlike relay output module, why do you need to connect the return of the supply to the CPU, as the function of the PLC is to merely to switch between output terminal and the common?
Another doubt is, for the 120/230 AC output module, what does the broken line connection indicate? Why there are two identical terminals 0L?
Hope anyone oblige.