Siemens SIMATIC ET 200AL, System Manual

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Parameters/address space
4.3 Explanation of the parameters
Analog input module AI 4xU/I/RTD 4xM12 (6ES7144-5KD00-0BA0)
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Equipment Manual, 08/2021, A5E32350124-AG
Diagnostics: Wire break channel n
Enabling of the diagnostics if the analog input module has no current flow or the current is
too weak for measurement at the correspondingly configured input.
Note
Wire break diagnostics
A wire break diagnostics is not possible for all measuring ranges and measurement types for
analog input channels.
The table below shows the rules you must observe in the case of a wire break in the
measuring ranges 1 to 5, 4 to 20 mA:
Table 4- 4 Parameters for wire break
Parameter Event Measured
value
Explanation
Wire break enabled
1
Wire break 7FFF
H
Wire break diagnostics
Wire break disabled
1
Underflow enabled
Wire break 8000
H
Measured value after leaving the under-
range
Diagnostics alarm Low limit violated
Wire break disabled
1
Underflow disabled
Wire break 8000
H
Measured value after leaving the under-
range
1
Measuring range limits for detection of wire break and measuring range undershoot:
• 1 V to 5 V: at 0.296 V
• 4 mA to 20 mA: at 1.185 mA
The table below shows the diagnostics that can occur for wire break with the measurement
type RTD/R.
Table 4- 5 Diagnostics with RTD/R
Diagnostics:
Wire break
Diagnostics:
Overflow
Diagnostics:
Underflow*
Event Process data Diagnostics
alarm per
channel
activated Deactivated Deactivated Wire break 0x7FFF Wire break
Deactivated Deactivated Activated Wire break 0x7FFF -
Deactivated Activated Deactivated Wire break 0x7FFF High limit
exceeded
Deactivated Activated Activated Wire break 0x7FFF High limit
violated
Deactivated Deactivated Deactivated Wire break 0x7FFF -
* This column does not apply to the measurement type resistance.
Diagnostics: Underflow channel n
Enabling of the diagnostics when the measured value falls below the underrange.