User Manual

Logical I/O blocks
Input blocks
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The values for slope [Slpe] and intercept [Icpt] must be defined specifically for
the application concerned in accordance with the I/O system in use and the
signal type.
For slope and intercept values for SBT products, see
Slope [Slpe] and Intercept
[Icpt]
. For sensors not listed, the following applies:
The values for [Slpe] and [Icpt], which are to be entered in the block, must first
be calculated. These values are derived from the individual [Slpe] and [Icpt]
values of the signal type and the signal transducer in accordance with the
following formula:
[Slpe] = (Slope
SignalType
/ Slope
SignalTransducer
)
[Icpt] = (Intercept
SignalTransducer
/ Slope
SignalTransducer
) + Intercept
SignalType
[Slpe] is calculated on the basis of:
[Slp] = (InterpolationPoint_y2 – InterpolationPoint_y1) / (InterpolationPoint_x2
– InterpolationPoint_x1)
Binary Input (BI)
The binary input block is the logical image, or memory map, of a binary switch
value and describes its properties. The parameters of the physical value are set
via the polarity [Pol], and the value is then available as the present value for
further processing. The Present Value is monitored for a given state. For
commissioning and test purposes, or in the event of an error, the Present Value
can be dissociated from the process and overwritten with a replacement value.
The following functions are integrated in the block:
● Inversion of the input value
● Interruption of input signal [OoServ] and replacement with [DefVal]
● Alarm value monitoring (OFFNORMAL alarm)
● Reliability monitoring [Rlb] (FAULT alarm)
● Change of state messages (events / system events)
● Runtime totalization and maintenance messages
Multistate Input (MI)
The multistate input block is the logical image, or memory map, of several
binary switch values or a direct hardware multistate value, and describes its
properties. The multistate capability is achieved by interconnecting a number of
individual binary states. The binary states are evaluated and mapped as
integers. Each integer in the series is allocated a text label which is further
processed and interconnected within the program as a current value. For
commissioning and test purposes, or in the event of an error, the Present Value
can be dissociated from the process and overwritten with a replacement value.
As an auxiliary function, the runtime total for this multistate input can be
registered and evaluated.
The following functions are integrated in the block:
● Interruption of input signal [OoServ] and replacement with [DefVal]
● Alarm value monitoring (OFFNORMAL alarm)
● Reliability monitoring [Rlb] (FAULT alarm)
Calculating [Slpe] and
[Icpt]