The Rockwell Automation 22 slots base chassis it is used for I/O modules. In addition to the I/O module slots, the backplane has slots for an Ethernet adapter and as many as 3 power supplies. Ethernet adapter allows the backplane to connect to other devices through the Ethernet network. Maximum safe voltage 60V DC
Input voltage range 18 to 32V DC
Dimensions 605 x 127 x 80 mm (23.8 x 5 x 3.15 in)