Endress+Hauser iTEMP TMT85, Руководство по эксплуатации

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Diagnostics and troubleshooting iTEMP TMT85
44 Hauser
• Off (Diagnostic event 041 sensor break (default category: F) is output when the alarm
limit is reached)
• On (Diagnostic event 042 sensor corrosion (default category: M) is output before the
alarm limit is reached. This allows preventative maintenance/troubleshooting to be
performed. An alarm message is displayed after the alarm limit is reached)
Corrosion detection is configured via the Field Diagnostic parameters in the Resource
Block. Depending on the configuration of diagnostic event 042 - "sensor corrosion", you
configure which category is output in the event of corrosion.
If corrosion detection is disabled, an F-041 error is output only after the alarm limit is
reached.
The following table describes how the device behaves when the resistance in a sensor
connection cable changes, depending on whether on or off is selected for the parameter.
RTD < ≈ 2 kΩ 2 kΩ ≈ < x ≈ 3 kΩ > ≈ 3 kΩ
Off --- --- ALARM (F-041)
On --- F-/C-/S-/M-042, depending on the configuration ALARM (F-042)
TC < ≈ 10 kΩ 10 kΩ ≈ < x ≈ 15 kΩ > ≈ 15 kΩ
Off --- --- ALARM (F-041)
On --- F-/C-/S-/M-042, depending on the configuration ALARM (F-042)
The sensor resistance can affect the resistance data in the table. If all the sensor
connection cable resistances are increased at the same time, the values given in the table
are halved.
The corrosion detection system presumes that this is a slow process with a continuous
increase in the resistance.
9.3 Application errors without messages
9.3.1 Application errors for RTD connection
For sensor types, see →  50.
Symptoms Cause Action/remedy
Measured value is incorrect/
inaccurate Incorrect sensor orientation Install the sensor correctly
Heat conducted by sensor Observe the face-to-face length of the sensor
Device programming is
incorrect (number of wires) Change the SENSOR_CONNECTION device
function
Device programming is
incorrect (scaling) Change scaling
Incorrect RTD configured Change the SENSOR_TYPE device function
Sensor connection (2-wire),
incorrect connection
configuration compared to
actual connection Check the sensor connection/configuration of
the transmitter
The cable resistance of the
sensor (2-wire) was not
compensated Compensate the cable resistance
Offset incorrectly set Check offset