Manual ibaFOB-SD
12
Issue 1.3
5.6
Remarks on the measurement principle
To measure SIMADYN-D system numeric values must be transported between the SD
system and the PC, which means that internal variables of the SD system may be
visualized and recorded. For recording purposes 2 different software packages are
provided by iba.
Request-SD
The definition of the signals to be measured is independent of the connected sys-
tem. All changes are done in ibaPDA. ibaPDA supports the functionality to inter-
pret the SD address book and communicate with the SD in a way that any inter-
nal variable of any processor may be requested from the PLC. To do that for
every SD CPU two function blocks must be included in the CFC/STRUC plan of
the SD-system. These FBs support overload protection to avoid high system
loads by ibaPDA.
SD/TDC-Lite
All measuring values are pre-programmed and a fixed part of the logic plan of
SD. Changing of signals requires a change in this plan. Process telegrams are to
be defined which transport the values from (to) ibaPDA (ibaLogic) containing 32
analog plus 32 digital variables each. There is no need for the SD address book.
ibaLogic only works with SD-Lite channels (bi-directional).
