A wide range of "off the shelf" instrumentation packages have been incorporated into control systems.
Standard sinking and sourcing signals, Analog to Digital, (A to D) and (D to A) translations, RS 232, RS 485, and Ethernet communications have successfully implemented.
The unit above is a leak checking system. One advanced approach for leak systems was to incorporate a calibration standard that allowed the system to routinely verify the calibration of the system.
In situations where a part fails to load properly, the control systems have been designed to make a number of attempts before alerting the operator that there is a problem. These and other "self-correcting" techniques have resulted in very dependable pieces of equipment.