Question
What is the difference between Group-2 High-density I/O Units and Special I/O Units used with the CS1 Programmable Controllers and C200HX/HG/HE Programmable Controllers?
Answer
Both have limits on the maximum number of Units that can be mounted according to the CPU Unit model. Group-2 High-density I/O Units can be mounted to the CPU Rack or Expansion Racks, but cannot be mounted to SYSMAC BUS Slave Racks.
The Special I/O Units can be used on CPU Racks, Expansion Racks, and the SYSMAC BUS Slave Racks.