Split-ranging of Control Valves can be done by following ways: 1. Single common pnuematic signal from Controller: i.e. using a single common pnuematic signal for both Control Valves. This way requires adding Volume Boosters to Control Valves or positioner to at least one Valve because without them as air volume is from a single I/P and is dividing between two CVs, response of Control Valve action will be slower as air volume is dividing. Benchset of each CV can be set separately and calibrated but it is a time-consuming procedure compared to other easier technique available discussed below. 2. Single common electrical signal output from controller: This common electrical signal from controller is fed to two I/P converters placed in series to each other i.e. both get th same electrical signal. Instead of adjusting Benchset of each CV, each I/P can be calibrated as per Valve behaviour requirement. Also, voltage drop in one I/P's electronic circuitry should not exceed a limit wh...
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