JUMO flowTRANS MAG H01, Operating Manual

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9 Advanced diagnostics functions
9.1.5 Electrode impedance monitoring
The impedance between the electrode and ground is monitored by means of a configurable minimal/
maximal threshold. This means that the transmitter can detect an electrode carbon bridge or an elec-
trode leak.
If the value exceeds or drops below the configured threshold, an alarm is triggered via the programmable
output, depending on the configuration.
Conditions for using the function:
• JUMO flowTRANS MAG S02:
The function is available in the nominal width range DN 10 to 300 (3/8 to 12 inch).
• JUMO flowTRANS MAG H02:
The function is available in the nominal width range DN 10 to 100 (3/8 to 4 inch).
• Maximum signal cable length in case of remote mount design type: 50 m (164 ft).
• For this function, the conductivity of the measurement medium must be between 20 µS/
cm and 20,000 µS/cm.
Additional installation conditions:
• For plastic pipelines, a grounding washer must be deployed upstream and downstream of the de-
vice.
• The measuring electrode must be free of deposits.
• The measuring pipe must always be completely filled, and the measurement medium may only ex-
hibit minor conductivity fluctuations.
9.1.6 Sensor measurements
This function includes monitoring the sensor temperature and monitoring the resistance of the coils in
the sensor.
Monitoring the sensor temperature
The temperature of the coils in the sensor can be monitored by means of a configurable minimal/maximal
threshold. When the configured thresholds are exceeded, an alarm is triggered via the programmable
output, depending on the configuration.
The coil temperature depends on the ambient temperature and medium temperature. The measurement
can be used, e.g. to monitor for excess temperature via the medium. The coil temperature is determined
indirectly via the coil direction current resistance.
Monitoring the coil resistance in the sensor
The coils in the sensor can be monitored for coil resistance by means of a configurable minimal/maximal
threshold. When the configured thresholds are exceeded, an alarm is triggered via the programmable
output, depending on the configuration.
9.1.7 Trend
The device has an internal memory in which the measured value for the electrode deposit and the con-
ductivity is stored cyclically as a data record at a definable interval (1 min to 45,000 min). A maximum of
12 of these data records are stored. As of the 13th measurement, the oldest data record is automatically
overwritten.
The external diagnostics tool (ScanMaster) can be used to extract the data records and analyze them
as a trend.