ABB 266 Operating Instruction page 54

266 Models - FOUNDATION Fieldbus
If SELECT_TYPE is Minimum, sort the remaining inputs by value. Transfer the lowest value to the output of the block. Set SELECTED
to the number of the input with the lowest value.
If SELECT_TYPE is Maximum, sort the remaining inputs by value. Transfer the highest value to the output of the block. Set SELEC-
TED to the number of the input with the highest value.
If SELECT_TYPE is Middle, sort the remaining inputs by value. If there are 3 or 4 values, discard the highest and lowest value. If two
values are left, compute their average. Transfer the value to the output of the block. Set SELECTED to zero if an average was used,
else set SELECTED to the number of the input with the middle value.
If SELECT_TYPE is Average compute the average of the remaining inputs and transfer the value to the output of the block.
Set SELECTED to the number of inputs used in the average.
Limit Processing
The computations to determine high and low limit conditions for the output can be complex. They should be done to the best of the
designer's ability. The limits of OUT should be able to tell a PID to stop integrating if the measurement cannot move.
Equations
With the SELECT_TYPE it is possible select the following algorithms
First Good Select the first available Input with Good Status
Select the minimum value of the Inputs
Minimum
Maximum Select the maximum value of the Inputs
Middle Calculate the middle of three inputs or the average of the two middle inputs if four inputs are defined
Average Calculate the average value of the inputs
Configuration hints
The minimum configuration for having the IS working and/or moving out from the OOS needs at least the following settings:
– Set the SELECT_TYPE with a valid value. It must be different by 0 and in the range 1 – 5.
54 OI/266/FF/ADD-EN Rev. B | 2600T Series Pressure transmitters