User Manual

Logical I/O blocks
Input blocks
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As these states are static, they must be set manually during commissioning.
Status Flag [StaFlg]
The status flag [StaFlg] indicates the state of the I/O block. This pin consists of
four Boolean values:
● IN_ALARM: Logic 1 (TRUE) if the event state pin [EvtSta] does not display
NORMAL as its value.
● FAULT: Logic 1 (TRUE) if the [Rlb] pin does NOT display the value
NO_FAULT_DETECTED.
● OVERRIDDEN: Logic 1 (TRUE) if the block point was overridden locally
(e.g., manual switch on I/O module). If this flag is set, [PrVal] and [Rlb] will
no longer display any changes in the physical input/output.
● OUT_OF_SERVICE: Logic 1 (TRUE) if the out-of-service pin [OoServ] is
active.
Default Value [DefVal]
For an input block, [DefVal] is transmitted to [PrVal] when [OoServ] is set to
TRUE.
For an output block, value [DefVal] is transmitted to [PrVal] when none of the
priorities (1…16) is active.
19.2 Input blocks
An input block is used to enable an input signal (e.g., a measured value) in the
program to be handled as a process value.
Analog Input (AI)
The analog input is the logical image, or memory map, of an analog measured
value and describes its properties. The raw data is converted and made
available in the form of a current value (Present Value) at the block output for
further processing within the program.
The following functions are integrated in the block:
● Conversion of the input signal with slope [Slpe] and intercept [Icpt].
● Interruption of input signal [OoServ] and replacement with [DefVal]
● Limit value monitoring (OFFNORMAL alarm)
● Reliability monitoring [Rlb] (FAULT alarm)
● Change of state messages (events / system events)
The measured raw value is converted into the measured present value in
accordance with a conversion curve. This present value is available at [PrVal]
for further processing within the program.
The conversion curve is a linear function which takes the following form:
[PrVal] = Raw value * Slope + Intercept
Processing and
displaying the current
value
Slope/Intercept