Samson 3730-3 - Determining the Ramp Times in Partial Stroke Tests

128 EB 8389 EN
Appendix
9.4 Determining the ramp times in partial stroke tests
Suitable ramp times for the partial stroke test can be determined by performing a full stroke
test.
To perform a full stroke test, observe section5.5.
The recording of the partial stroke test in the data logger is described below. The Type3730-
5 (1.6x) and Type3731-5 do not have the data logger function. The test can be recorded in
these positioners using the Trend-Viewer in TROVIS-VIEW (uEB6661).
1. Adjust the FST diagnostic parameters as follows:
'Tolerance limit for step response' = 2.0% (WE)
'Activation of the ramp function' = Yes (WE)
'Ramp time (rising)' = 900s
'Ramp time (falling)' = 900s
'Settling time before test start' = 10s
'Delay time after step' = 4.0s
'Scan rate' = 'Min. recommended scan rate'
2. Adjust 'Scan rate' of the data logger to 0.2s and start the data logger ('Selection' = Per-
manent). See section4.2.
3. Start full stroke test and change directly to the data logger graph.
4. After the full stroke test is nished, stop the data logger and save the data.
5. Analyze the logged data: If the valve position follows the set point closely, the adjusted
ramp times can be used for the partial stroke test. If this is not the case, repeat the full
stroke test with different ramp times until the valve position follows the set point (Fig.21).
NOTICE
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Note