2.35 MDSW Function Block,
Example
Figure 2-32 shows a Function Block Diagram using an MDSW function block.
Application: External mode switching of the PID Block - changing a loop to MAN, to AUTO, to LOCAL
SP, or REMOTE SP.
Note: Mode switching is also provided as an integral part of the Operator Panel, Loop Displays.
The MDSW (Mode Switch) Function Block is used exclusively with the MDRQI (Mode Request Input) of
the PID, ON/OFF, CARB< or TPSC Function Block. Its output provides encoded switch commands to the
PID Block.
All inputs are OFF to ON edge-triggered, requiring a separate input for each action. The example shows
digital inputs as the transfer inputs but any digital status could be used.
3/99
continued
Figure 2-32 MDSW Function Block Example
Function Block Reference Guide
Function Blocks
99