Endress+Hauser prowirl 77, Руководство по эксплуатации

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Function group: MEASURING SYSTEM DATA
Temperature
entry The flowmeter (measuring pipe and bluff body) expands according to the
process temperature and affects the calibration of the instrument. This effect is
proportional to the difference from the calibration temperature 293.15 K (20 °C).
If the process temperature is constant and accurately known the calibration
factor can be compensated numerically by entering the process temperature in
this function.
Input:
Value range: 0...999 K (Kelvin); this corresponds to –273.15...726 °C
Factory setting: 293.15 K ; this corresponds to 20 °C
Caution:
The approved operating temperature of the measuring system is not affected by
this setting. Note therefore the application limits given in Section 9 “Technical
Data” (see page 55).
Select gain
range
All Prowirl 77 flowmeters are set for optimum operation at process conditions
stated by the customer when ordering.
Under certain process conditions the effects of interference signals (e.g. by
strong vibration) can be suppressed by adjusting the amplifier. Adjusting the
amplifier can also extend the measuring range:
•
For slow flowing liquid with low density and weak interference effects.
→
choose a higher amplification level.
•
For fast flowing fluid with high density and strong interference effects
(plant vibration) or pressure pulses
→
choose. a lower amplification level.
An incorrectly set amplifier can have the following consequences:
•
The measuring range is limited so that small flow rates are no longer detected
or indicated
→
increase amplification.
•
Unwanted interference effects are detected so that flow is still indicated
even under no-flow conditions
→
reduce amplification.
Selection:
VERY LOW, LOW, NORMAL , HIGH
Caution!
Prowirl 77 PROFIBUS-PA 6 Device Functions
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