FC410 with Modbus
Operating Instructions, 02/2016, A5E33120874-AC
69
Functions
7
In the following the main functionalities of the device are described in detail.
For overview of all functions and parameters, refer to Modbus holding registers (Page 117).
7.1
Process values
According to standard practice with serial communication the Modbus RTU signal reports
primary process values and error status strictly with SI units
1)
– kilogram, meter, second and
degree Celsius.
1)
1 kg/s of water flow equals 0.001 m³/s of volume flow, and 3600 kg/h.
The process values are updated every 10 ms (100 Hz update rate) synchronous with the
DSP update cycle.
Process value parameters
The process values are:
●
Massflow (MassflowValue) [kg/s]
●
Volumeflow (VolumeflowValue) [m
3
/s]
●
Density (Density) [kg/m
3
]
●
Process media temperature (FlowMediaTemp) [°C]
7.2
Zero point adjustment
In the following the automatic zero point adjustment function is described. For further details,
see Zero point adjustment.
Note
Preconditions
Before a zero point adjustment is initiated, the pipe must be flushed, filled and at an absolute
flowrate of zero preferably also at operating pressure and temperature. Refer to appendix
Zero point adjustment (Page 141) for more details.
Note
Change of parameters during zero point adjustment
Do not change any other parameter during the zero point adjustment procedure.