CiDRA SONARtrac PW VF-100 - Manual (Page 160)

20834-01 Rev 04 Page 8-16
8.3.5 VF & GVF Damping (Filter)
The Damping (Filter) is used to reduce the noise of a signal through
the use of a first order lag filter with a fixed time constant. The time
constant of the filter is set by the user.
8.3.5.1 State
State is used to ‘Enable’ or ‘Disable’ this option.
8.3.5.2 Time Constant
Time Constant is used input range of values that can be applied.
Ranges of 0
– 600 seconds can be input with 3 seconds as the factory
default.
Care must be taken when choosing the time constant for the damping
filter as the response time for the reported measurement will increase
as the magnitude of the time constant is increased.
If the time response of the reported measurement is critical then the
‘VF & GVF Noise Filter’ should be used instead of the damping filter.
8.3.6 VF & GVF Noise Filter
The VF & GVF Noise Filter has been designed to provide both steady
state noise attenuation and quick transient response. Under steady
state conditions the filter will use a long time constant in order to
attenuate noise on the signal. Once the measurement begins to ramp
up or down, the filter will reduce the filter time constant to allow the
meter output to track the changes with a faster response time.
8.3.6.1 State
State is used to ‘Enable’ or ‘Disable’ this option. Factory default is
‘Disable’.
8.3.6.2 Magnitude
The Magnitude choices are ‘Low’ or ‘High’. The high setting differs
from the low setting with more damping in both the transient and
steady state condition.