Technical Specifications

ValVueFF Software Interface to FVP
152
GE Energy
Recommended Scan
Time [s]
Recommended scanning time.
Scan Time[s] This determines the measuring time. Use Recommended Scan
Time as a guide to set the scanning time. Scanning time: 20 to
3600 sec.
To get the result in shorter period, decrease the Scan time. To get
more specific information, choose a longer time to get more sam-
ple points.
Deviation Margin[%] Allowable deviation. - The measurement is performed in Propor-
tional control algorithm. For this reason, deviation between the
set point value and the position value can occur due to the
non-linear characteristic existing in the control system. (I/P hys-
teresis, Valve deadband etc.). Basically, this value does not need
to be changed from the default value. But, if the stem position did
not reach the desirable point, then increase this value or if stem
position far exceeds the desirable point, then decrease this value
to make the measurement correctly. The valid range is 0 to 500%.
Sampling Interval
[ms]
This parameter is used for High Resolution Signature only. Sam-
pling rate: 200 to 1000 ms.
High Resolution Actuator Signature
Use this for measuring the actuator signature in high resolution. The function measures
the in-out characteristic of the control valve in time sampling mode. The number of
measuring samples depends on the time of round-trip, and can be obtained by the
following calculation:
(Scan Time/Sampling rate) x 1000 [point]
Before measuring the signature, FVP performs an offset measurement, the same as in
Auto Tune, to prepare for the measurement. For parameter details refer to “Extended
Actuator Signature” on page 151.