58
EB 8389-1S EN
Leakage sensor
Phase 1 successful:
The sound pressure level
exceeded the adjusted 'Sensitivity sound level'
(10 dB) between set points 4 and 5. Phase 2
starts.
If the 'Sensitivity sound level' is not reached
after the valve has moved to all eleven set
points, the test is canceled. The canceled test
is logged with a time stamp and the 'Test in
-
formation' reading indicates 'Test failed:
sound level change too small'.
Phase 1 not successful:
The difference in sound
pressure level between two neighboring set points
is smaller than the 'Sensitivity sound level'
(10 dB). The process reference test is canceled.
Phase 2:
A 0.30 % band is placed around
the last set point that the valve moved to.
One third of this band lies in front of the set
point that the valve moved to and two thirds
of the band lies behind it. The band itself is
subdivided into eleven fixed points. Each
fixed point is located at a distance of 0.03 %
to the next point. The valve moves to the new
fixed points one after the other. After reach
-
ing a fixed point and after the 'Settling time
before sound level measurement' has
elapsed, the leakage sensor measures the
sound pressure level.
Phase 2 successful:
The 'Sensitivity sound level'
(10 dB) is reached between the first and last
newly defined points. The process reference test is
successfully completed.
The process reference test is successful when
the difference between the first and last new
-
ly defined points is larger or equal to the ad
-
justed 'Sensitivity sound level'.
If the 'Sensitivity sound level' is not reached
after the valve has moved to all eleven newly
defined points, then the change in sound
pressure level is too low. In this case, phase
3 starts.
Phase 2 not successful:
The difference in sound
pressure level between the first and last newly
defined points is lower than 'Sensitivity sound
level' (10 dB). Phase 3 starts.
