Siemens SIMATIC ET 200AL System Manual page 2141

Supported functions
7.1 Calibrating analog modules
● Command: The field "Command" indicates which actions the user has to execute during
the current calibration step. Here you execute the specified actions and confirm them with
the "Next" button. The module now executes all actions required for the current
calibration step. If the calibration step was error-free, the next calibration step takes
place.
The instructions in the "Command" field are to be performed additively. For example, after
you have applied the voltage/ground to the terminals 3/4, these connections must remain
in place during the execution of the next calibration step.
● Status: Depending on the set type of measurement, several calibration steps are required
for calibration of a channel. The field "Status" indicates whether or not the last calibration
step included errors. If an error occurs during processing of a calibration step, the error is
displayed here and calibration of the channel is aborted. All calibration values recorded
up to this point are deleted. The calibration values that were in effect prior to the start of
the user calibration are effective once again.
Note
Calibrators
If the "Wire break" diagnostics is activated for analog input modules, a test current is
applied to the line for the measuring types "Resistance", "Thermistor" and
"Thermocouple". This applied test current can result in inaccurate measured values in
some calibrators. The wire break monitoring is therefore automatically disabled in some
analog modules during the calibration.
To avoid the risk of inaccurate measured values, we recommend you disable the "Wire
break" diagnostics during the calibration of analog input modules.
Result
Calibration sets new settings for the channel.
Error occurrence
If an error occurs during the calibration, the module cancels the calibration. All calibration
values recorded up to this point are lost. The channel to be calibrated will then have the
same settings as before the start of calibration.
110
Analog value processing
Function Manual, 06/2014, A5E03461439-AC