Weidmuller AI8 - Multi channel signal transmitter - Handbuch (Seite 29)


Calculated Variables
Each alarm and analogue output can operate on any of the measured
variables. Alternatively, the unit can calculate values for monitoring or
setting the analogue output level. Options are maximum, minimum or
average of any of the eight measured values or the difference between
any two. For more complex applications, you can also use formula one
and formula two to calculate values.
Formula one is calculated using:
FM1 = (MV1 x MV x MV x MV) / (MV5 x MV6 X MV7 X MV8)
Formula two is calculated using:
FM = (MV1 - MV) x MV
Note 1: If you need to incorporate some factor into the equation you
must do it by scaling the inputs.
Note : The units used for calculated values are taken from the lowest
numbered measured value selected, for example, if you are averaging
MV, MV and MV5, the units will be the same units as MV.
Note : The average function is equivalent to the sum of the selected
values (scaled to give full scale output when all selected values are at
their highest).
Output Setup
There is one output sub-menu for each analogue output. For each
channel you select the output type and range, select a measured value
or set up a calculated value for the output. Then you select the range
represented by the output signal.
Alarm Setup
Before the individual sub-menus for each alarm the AI8 asks you to
secure the setpoints and set up the alarm reset mode (automatic or
manual). Secure setpoints cannot be adjusted in run mode. Manual
reset alarms must be accepted by an operator before they will reset.