Endress+Hauser HART Proline t-mass I 300, Руководство по эксплуатации

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Maintenance Proline t-mass I 300 HART
156 Hauser
12.1.3 Recalibration
The long-term stability of a measuring device depends on the integrity of the sensor,
among other things. Impurities can also cause a coating to form on the sensor, which can
cause a change in the measuring signal. Therefore, if the sensor is used in applications in
which impurities (such as oil residue or dust) can occur, it is advisable to check the sensor
for contamination at regular intervals and clean it if necessary (see →  155). The
intervals depend on the type, condition and extent of the contamination.
Process conditions such as thermal shocks or constant variations in temperatures can
create the conditions in which the measuring signal drifts over time. A recalibration can
rectify these undesired changes in the measuring signal and restore the original measuring
state.
Determining the recalibration intervals:
• In the event of critical measurements and in order to determine the recalibration
intervals, a calibration check should be performed once a year.
The next recalibration can then be scheduled earlier or later depending on the results of
these checks.
• A recalibration every three years is recommended for non-critical applications or for use
in clean and dry gases.
• Heartbeat Verification can be used to help determine when a recalibration should be
performed. By performing verifications regularly, it is possible to compare the
verification results with the initial values determined at the factory. If these values
deviate from one another, this can indicate that the device needs to be recalibrated.
12.2 Measuring and test equipment
Hauser offers a wide variety of measuring and test equipment, such as W@M or
device tests.
Your Hauser Sales Center can provide detailed information on the services.
List of some of the measuring and testing equipment: →  161
12.3 Hauser services
Hauser offers a wide variety of services for maintenance such as recalibration,
maintenance service or device tests.
Your Hauser Sales Center can provide detailed information on the services.