Samson 3730-3 Operating Instructions Manual page 95

Phase 2: A 0.30 % band is placed around
the last point that the valve moved to. One
third of this band lies in front of the point
that the valve moved to and two thirds of the
band lies behind it. The band itself is subdi-
vided into eleven new measured points. Each
measured point is located at a distance of
0.03 % to the next point. The valve moves to
the new points one after the other. After
reaching a point and after the 'Settling time
before level measuring' has elapsed, the
leakage sensor measures the sound pressure
level.
The reference test is successful when the dif-
ference between the first and last newly de-
fined points is larger or equal to the adjusted
'Activation level'.
Phase 2 successful: The 'Activation level' (10 dB)
is reached between the first and last newly de-
fined points. The reference test is successfully
completed.
If the 'Activation level' is not reached after
the valve has moved to all eleven newly de-
fined points, then the change in sound pres-
sure level is too low. In this case, phase 3
starts.
EB 8389 EN
Phase 2 not successful: The difference in sound
pressure level between the first and last newly
defined points is lower than 'Activation level' (10
dB). Phase 3 starts.
Phase 3: The valve moves to the user-defined
points valid for phase 1 one after the other.
This is plotted in a sound level vs. travel
graph. The graph shows where the point of
activation is and to which value the 'Activa-
tion level' must be reduced to allow the test
to be completed successfully.
Defining parameters
1. Switch to manual mode.
2. Define parameters for reference test. See
Note concerning changing measured
points.
3. Start reference test.
The start of the reference test is docu-
mented in the Time stamp.
'd8' and 'tEST' are indicated in alternat-
ing sequence on the positioner display.
Operation > Operating mode
1. − Target mode (Code 0): Manual
Leakage sensor
1)
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