Yokogawa YVP110 - Manual (Page 107)

<19. Diagnostics>
19-3
IM 21B04C01-01E
19.3.2 Signatures and Relevant
Parameters
The following describes each signature and the
relevant parameters.
(1) Standard Actuator Signature * 1
The standard signature is the fundamental input-to-
position characteristics of the valve, measured at
10% through 90% of the full stroke in 10% intervals
over a round trip.
• The following can be set in a setting parameter
STD_ACT_SIGN_SET:
Recommended Scan Time [seconds]
Scan Time [seconds]
Deviation Margin [%]
• Performing measurement sets the pressure
data in SIGN_DATA_X and the position data
(%) in SIGN_DATA_Y.
• This signature can be saved to non-volatile
memory within the YVP110. To do so, Select
“2” (Save as a Factory data) or “3” (Save
as record data) in SIGN_ DATA_SAVE and
execute saving. The standard signature
previously saved is then overwritten.
It is recommended to save the signature data
taken at the installation as a “Factory data” and
that of the latest measurement as a “Record
data.”
(2) Extended Actuator Signature * 1
The extended actuator signature is the input-to-
position characteristics of the valve, measured at
arbitrary positions within the full stroke of the valve.
As the positions of measuring, 50 points can be
specified for each direction of the valve actions,
totaling 100 points.
• The following can be set in a setting parameter
EXT_ACT_SIGN_SET:
Lower Setpoint [%]
(point to start the measurement)
Upper Setpoint [%]
(point to finish the measurement)
Recommended Scan Time [seconds]
Scan Time [seconds]
Deviation Margin [%]
Sampling Rate [milliseconds]
(not used in this function)
• Performing measurement sets the pressure
data in SIGN_DATA_X and the position data
(%) in SIGN_DATA_Y.
(3) High Resolution Actuator Signature * 1
The high-resolution actuator signature is the input-
to-position characteristics of the valve, measured
with high resolution while sampling data at the
specified time rate. Up to 100 data values can be
stored in the memory of the YVP100. After this limit
is reached during measurement, the stored data will
be overwritten from the leading data in order. Using
ValveNavi, users can continue measurement while
uploading the measured data.
• The following can be set in a setting parameter
EXT_ACT_SIGN_SET:
Lower Setpoint [%]
(point to start the measurement)
Upper Setpoint [%]
(point to finish the measurement)
Recommended Scan Time [seconds]
(not used in this function)
Scan Time [seconds]
Deviation Margin [%]
Sampling Rate [milliseconds]
The sampling rate can be set within the range
of 200 through 1000 milliseconds. The total
number of measured samples can be obtained
by the following formula:
Scan time / sampling rate × 1000 [points]
• Performing measurement sets the pressure
data in SIGN_DATA_X and the position data
(%) in SIGN_DATA_Y.
(4) Step Response Test
The step response test measures time-series
changes in the valve position in response to
a sudden change (step) in the setpoint of the
positioner from the preset initial setpoint to the
destination setpoint.
• The following can be set in a setting parameter
STEP_RESP_SET:
Initial Setpoint [%]
Destination Setpoint [%]
Sampling Rate [milliseconds]
Number of Samples [points]
The sampling rate can be set within the range
of 20 through 1000 milliseconds (corresponding
to the measurement period of 0.4 through 600
seconds). The number of samples can be set
to up to 600.
• Performing measurement sets the positioner
setpoints in SIGN_DATA_X and the position
data (%) in SIGN_DATA_Y.