Laurel Electronics LAUREATE SERIES 2 COUNTER-TIMER-SERIAL INPUT METER - Manual (Page 75)

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22. GLOSSARY OF TERMS
Adaptive filter threshold
A threshold which causes an adaptive moving average filter to be reset to the
latest reading when the accumulated difference between individual readings
and the filtered reading exceeds that threshold. Adaptive moving average filter-
ing allows a meter to respond rapidly to actual changes in signal while filtering
out normal noise. The accumulated difference is also reset to zero when the
latest reading has a different polarity than the filtered reading. A low adaptive
filter threshold is normally selected. A high filter threshold should be selected if
the signal has large transients.
Alarm, latched
An alarm which stays actuated until reset.
Latched alarms can shut down machinery or
a process when an operating limit has been
exceeded, or maintain an alarm condition
until acknowledged by an operator.
Alarm, non-latched
An alarm which changes state automatically
when the reading rises above a specified limit
and changes back automatically when the
reading falls below a limit.
Autofilter A selectable digital filter mode which auto-
matically selects an appropriate moving aver-
age filter time constant from 0.08 sec to 9.6
sec for the encountered noise condition.
Batch control An operating mode of the Extended counter
with a relay board, where the counter is used
to control repetitive fill operations by counting
up from zero to a preset, or counting down
from a preset to zero.
Calculated total
While most totals are based on direct pulse counts, certain totals are calculated
as running totals based on displayed rate (e.g., Total A, Rate A). The totalizing
process assumes that rate is displayed in units per second, such as 300
gallons per second, allowing a scale factor of 1 to be used. If the rate is not in
units per second, a different scale factor has to be applied.
Coordinates of 2 points method
A scaling method where the coordinates of 2 points are entered. For a pulse
rate input, the first entered point is would be low frequency in Hz and low
desired reading. The second entered point would be high frequency in Hz and
high desired reading.
Counts The reading displayed on the meter ignoring the decimal point.