A representative from Richards Industries approached ASIC with a request to build controls for their proprietary flow test loop. Richards Industries is a leading provider of a variety of industrial valves for the chemical, petrochemical, pharmaceutical and food processing industries. Other sectors include paper products, tire and rubber, machinery and electrical equipment, transportation equipment and energy industries. Their flow test loop is designed to test control valves and regulators to determine flow capacities and product characteristics under a range of operating conditions using water as the operating fluid.


The control requirements dictated the ability to monitor several 4-20mA analog inputs from several different Siemens pressure transducers. Based on the analog inputs, the flow test loop controls had to log data in several different configurations. Richards also required some kind of user interface for the test loop; their preference was for an HMI touchscreen.

The control system specifications included the following parameters:

Interfacing with a smart pump variable frequency controller

800:1 rangeability for flow to the test section

Multiple control circuits and control modes

Pressure control to within 0.1 psi accuracy

Specified rates of flow increases

Specific Data Acquisition formats for each type of flow test

ASIC Solution

ASIC proposed and then manufactured controls using Unitronics Vision 1210 HMI + PLC. Unitronics HIM + PLC is an all-in-one controls solution for just about any automation process. The Unitronics 1210 HMI is a spacious 12″ touchscreen. We programmed an easy to use GUI that showed a high quality image of Richards’ flow loop. The program allowed the user to manipulate flow valves and data-logging scenarios based on the valve model being tested and other testing requirements. We also programmed the Vision 1210 PLC PID loop to control the test loop pump based on user defined pressure settings. The system has been installed and is in operation.