Siemens SIMATIC 505 - Reverse Acting

Selected Functions
5-17
5.9 Reverse Acting
The Reverse Acting option is available only in closed-loop mode for velocity
loop and pressure loop. Y ou select this option with bits 9 and 10 of constant
#14:
Bit 9 V elocity Loop
0 = No Reverse Action
1 = Reverse Acting
Bit 10 Pressure Loop
0 = No Reverse Acting
1 = Reverse Acting
For example: with Reverse Acting selected, the module performs the
following calculation:
Actual Output = 32000 – PID loop output
If loop output = 32000, then reverse acting output = 0.
If loop output = 0, then reverse acting output = 32000.