For our Thermic fluid TP66 application we are used DP transmitter for flow measurement. Orifice assembly is used as a flow element.
Currently we are facing flow variation issue in transmitter. The flow is without pressure and temperature compensation. There is 25-30% in flow value when we are comparing it with pump flow. Pump flow, we are deriving from motor current as well as inlet and outlet pressure.
Flow meter is showing 145 m3/hr and as per pump curve it should be 190 m3/hr. Whenever i check flow value wrt DP, it matching perfectly. The flow transmitter is configured for 0-5000 mmWC and output is square rooted.
Orifice sizing is done for operating temperature.
Transmitter model - Emerson 2051CD2A22A1AB4L4M5D4Q4
My questions are,
- Density compensation need to be done in control system??
- Is transmitter sensing liquid column (mmWC) which is supposed to
measure thermic fluid DP?