Technical Specifications

ValVueFF Software Interface to FVP
110
GE Energy
I (seconds) Integral time or reset time, is the time constant of integral control.
Higher values of I cause less integral control action and increase
loop stability. However, higher values of I increase the time to
eliminate a steady- state position error. 0 turns off integral action
and results in a steady-state position error. Sustained deviation
can result in failsafe action if T2 is set. Therefore, 0 must be
avoided for use in most applications. The default value of 15 sec-
onds is normally changed by Auto Tune.
D (seconds) Derivative time or rate time is the time constant of derivative con-
trol. Larger derivative time causes more derivative control action.
0 disables derivative action.
Derivative Gain
(dimensionless)
Derivative gain controls the maximum response to rapid position
change. The default value of 5 is normally adequate.
Dead Zone (%) When the valve position is within its Set Point +/- the dead
zone, no additional position control is performed. This value is
normally 0%, however for high friction valves (e.g. valves with
graphite packing) a higher dead zone helps avoid limit cycling
due to the stick/slip action of the valve. In these cases the
dead zone can be set at 0.1% to 5%