Please refer to the attached image.

The display is set to show x3 lines. In the setting 1st line shows PV, 2nd Flow & 3rd Output.
Water line is PVC & currently empty that's why F051 error is generated.

I have seen the values of other process variables like volume flow, mass flow & even velocity: all are zero.

However I cannot understand why mA output is 22? Sensor detects pipe is empty but PV is this 11.25 PV value? Range is 0-10 m^3/hr

 

It's not a problem, it's a standard feature on 4-20mA transmitters: fault mode.

The control system needs to know that there is critical process error, an empty pipe, which is apparently coded F051 by this flow meter. The transmitter drives the analog output into fault mode, which in this case is fail High, a full, offscale 22mA output, 10% above the maximum valid range reading of 20mA.

The fault mode can be configured for fail High or fail Low where fail Low is something around 3.6mA