Ronan X96S MASS FLOW GAUGE - Manual (Page 20)

16
Density Filtering Menu
The Density Filtering menu is used to configure the parameters associated with the Mass Flow measurement filter. It contains the
following items:
ITEM FUNCTION
Type Shows and allows the user to change to the RC 1 st Order type of filtering (Resistance
Capacitance Filtering) or the Walking Average type of filtering.
Dyn Track Shows the current state of the dynamic tracking filter (enabled or disabled) and allows
the user to change the state. If disabled the filter uses only the Slow TC (time
constant).
Sigma Shows the (sigma) multiplier used to determine maximum number of raw counts
variation (for scintillation) or raw analog value (for ion chamber) that the input can
vary from the current filtered counts before changing to the dynamic filter. Sigma is
the square root of the current filtered counts. Also allows user to change this number.
Fast TC Fast Time Constant value to be used when the Fast Counter reaches zero.
Fast Counter Shows the fast count down counter value. If gauge has been in dynamic tracking long
enough to be using Medium filter and the raw counts continued to exceed the sigma
value, the fast counter value is decreased each consecutive scan. The Fast counter
value resets and returns back to the original value if the raw counts do not continue to
exceed the sigma value. Once the Fast TC is triggered, it will continue to be used until
the counts are within the sigma value for the Fast counter number of times
consecutively. Also allows user to change this number.
Medium TC Medium Time Constant value to be used when the Slow Counter reaches zero.
Slow Counter Shows the slow count down counter value. If gauge is in dynamic tracking, and the
raw counts continued to exceed the sigma value, the slow counter value is decreased
each consecutive scan. The Slow counter value resets and returns back to the original
value if the raw counts do not continue to exceed the sigma value. Also allows user to
change this number.
Slow TC Slow Time Constant value to be used if the Slow Counter has not reached zero.
Noise Filter Shows the maximum number of potentially erroneous measurements in a row to
bridge before deciding that a step change has occurred in the flow value. Also it allows
user to change this number. Erroneous measurement is defined when the raw signal is
4 times the pre-selected sigma multiplier by the user.
Monitor Shows the current state of the filtering mechanism.
Monitor (filter state) is one of the following:
ITEM MEANING
ERROR Filter is not initialized (this state should not occur during normal operation of the
X96S Mass Flow Gauge).
FILL The slow filter buffer is filling.
TRACK The (slow or medium or fast filter buffer is filled and the filter is tracking changes in
the flow value.
REFILL A step change has occurred and the walking average buffer is refilling.