Device functions - thermal measuring systems
Proline Fieldcheck
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Hauser
12.1.2
Group VERIFICATION TRANSMITTER
In the VERIFICATION TRANSMITTER group, a measuring device can be checked for the following
characteristic values:
• Functionality and deviation in providing a required power rating at the heated sensor element in
four points of the range available.
• Functionality and deviation in resistance measurement at four prespecified calibrated resistors.
• Functionality and deviation in the flow measurement (based on the set point preset by Fieldcheck)
• Functionality and deviation of the current and frequency outputs if these outputs are available in
the measuring device. The specified set points correspond in the gradation to the measuring points
when determining flow.
Data bus outputs such as PROFIBUS or FOUNDATION FIELDBUS cannot be directly checked by
Fieldcheck.
Verification of transmitter
Checking the linearity of the amplifier:
Simulated flow at four measuring points which are determined via the 100% full scale value.
Checking a current output:
Each current output can be verified in the configuration in the measuring device (CURRENT
RANGE function (0-20 mA, 4-20 mA)) in the same gradation (5% to 100%) as the amplifier. For
this purpose, the current output must be directly connected to the current input of Fieldcheck. If
more than one current output is available, verification takes place in several, menu-guided steps.
Checking a frequency output
(FREQUENCY operating mode):
Each frequency output can be verified in the configuration in the measuring device (END VALUE
FREQUENCY, OUTPUT SIGNAL functions) in the same gradation (5% to 100%) as the amplifier.
For this purpose, the frequency output must be directly connected to the frequency input of
Fieldcheck.
Checking a frequency output
(PULSE operating mode):
Each pulse output available can be verified in the configuration in the measuring device (PULSE
WIDTH, OUTPUT SIGNAL functions).
Sensor test
This test can be compared to zero point adjustment for the measuring device. The power in the
heated sensor element is set to ZERO and the process is interrupted until the temperature
differential of the two sensor elements is leveled out. This can take up to 1 minute.
The temperature differential that then applies is read and evaluated.
