Siemens SITRANS LG270 Operating Instructions Manual page 71

and is used universally. PID blocks can be cascaded if this is necessary or requested due to differ-
ent time constants with the primary and secondary process measurement.
Fig. 42: Schematic presentation function block PID Control
Function block Output Splitter
The function block "Output Splitter" generates two control outputs out of one input. Each output is
a linear image of a part of the input. A retrograde calculation function is realised by using the linear
imaging function inversely. A cascading of several Output Splitters is supported by an integrated
decision table for the combinability of inputs and outputs.
Fig. 43: Schematic presentation function block Output Splitter
Function block Signal Characterizer
The function block "Signal Characterizer" has two channels the outputs of which are not in linear
relation with the respective input. The non-linear relation is defined by a look-up table with individu-
ally selectable x/y-pairs. The respective input signal is imaged on the corresponding output, hence
this function block can be used in a control loop or signal path. Optionally the function axis can be
exchanged in channel 2 so that the block can be also used in a reverse control loop.
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PBD-51041071 SITRANS LG270 - Operating Instructions