A control system has an I/O bank with a communication module controlling a plurality of Input/Output modules operably connected to its communication backplane and a valve manifold having a communication module serially connected to the backplane of the I/O bank. The I/O bank with a plurality of Input/Output modules is constructed to be connected to a plurality of field sensors or loads. The valve manifold with a plurality of solenoid valves is constructed to be pneumatically connected to a plurality of field devices.