Technical Specifications

ValVue Digital Communications Software Ver. 2.80
222
GE Oil & Gas
Step 7: New Parameters
After you close the Setup Wizard Diagnostic Graph, the PID Values window appears
(See Figure 26).
The PID Values window shows the previous and the newly calculated (as a result of auto tune)
PID values. To complete the auto tune process:
 Close the window by clicking Exit.
Figure 26 New PID Values After Setup Wizard Calibration
Parameter Definitions
P Proportional gain in %. Common values for the controller are 50 for
small valves up to 4000 for large valves.
I Integral time or reset time in 1/10th sec, is the time constant of inte-
gral control. Higher values of I cause less integral action, however a
value of 0 gives no integral action. Common values are 10 to 200.
D Derivative time or rate time (msec) is the time constant of derivative
control. Common values are 10 to 100.
PAdjust Valves often have significantly different response when filling verses
exhausting. The proportional gain is adjusted by adding Padj (%) to P
when the valve is exhausting.