User`s guide

Appendix B - Loop Application Examples
PID Control Algorithms
242 UMC800 Control Builder User’s Guide Release E
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Example 5 - Hi or Lo input selection for PID control
Configuration of the MMA Block, (Minimum,
Maximum, Average, Sum, or Std Dev) will require
setting the number of inputs to be used.
In this application, control is determined by
automatic selection of the lowest or highest sensor,
such as a thermocouple. As shown, the MMA
block is configured for highest (MAX).
Configure the analog input failsafe value (for
T/C’s), for proper selection if an open (FAIL)
condition occurs.
Example 6 - Transferring PID loop manual/auto status
The mode output of the PID Block is used
exclusively with the MDFL (Mode Flags) Block.
Any of the status outputs may be referenced by a
Signal Tag or may be transferred externally using a
DO.
The output shown is ON when in Manual and OFF
when in Automatic.