Attributes Of An Rtd/Analog Input For Feeder Terminal Configuration; Rtd/Analog Input Configuration Example - ABB REF 54 Series Technical Reference Manual, General

REF 54_
5.1.9.7.
5.1.9.8.
58
Feeder Terminal
Technical Reference Manual, General
Attributes of an RTD/analog input for feeder terminal
configuration
The value and the validity of the input can be issued for each RTD/analog input by
the attributes AI# (REAL type) and AI#IV (BOOL type), where # denotes the
number of the input. These attributes are available in the feeder terminal
configuration and can be used for different purposes.
Value (AI#)
The AI# value represents the filtered absolute value of the physical input with the
unit according to the selected measuring mode, that is, V, mA, Ω or °C.
Invalidity (AI#IV)
The AI#IV attribute represents the invalidity status of the input. The attribute is set
to FALSE when the value (AI#) is valid, and to TRUE when the value is invalid. The
input is invalid when one or more of the following conditions are true: the measured
value is outside the defined limits (see the parameters "Input high limit" and "Input
low limit"), an open-loop condition is detected (only possible on resistance and
temperature measuring modes) or the continuous recalibration of the module has
failed. The value (AI#) is not locked when the invalid attribute is set to TRUE, that
is, the invalid value is available for inspection.

RTD/analog input configuration example

The RTD/analog inputs are supported in the Relay Configuration Tool by the
general measurement function blocks MEAI1...MEAI8. As an example, to monitor
temperature using a PT100 sensor, the measured value of the RTD/analog input is
connected to the function block by connecting the value attribute RTD1_6_AI1 to
the RawAI input of the function block. The output HighAlarm is used to activate a
relay contact when the temperature exceeds a preset limit. The measured
temperature is displayed on the MIMIC view of the HMI by the connected
MMIDATA1 function block. To avoid unnecessary activation of the relay contact
in case of a fault, the corresponding invalid attribute of the RTD/analog input
RTD1_6_AI1IV is connected to the IV input of the function block.
Fig. 5.1.9.8.-1 RTD/analog input configuration example
1MRS750527-MUM
meaix1