User guide

AccuMeter Controller Chapter 11: Configuring a new PLC 79
FIFO DATA Tab
• PRIMARY FIFO. This is the primary FIFO that contains up to 20 slots that is used in
the analysis of the weight loss. This FIFO will be filled to the NUMBER OF POINTS
IN FIFO (FIFO Setup Tab). Once this happens the range of these values is used to
calculate a %Dif that is displayed below the FIFO. If the %Dif is below the
ALLOWABLE % DIFFERENCE FOR STEADY (FIFO Setup Tab) then the FIFO
STEADY message will be shown below the FIFO.
• SECONDARY FIFO. This FIFO is used when an erroneous sample is measured by the
weight loss algorithm. If the %error of the current sample is greater than the
ALLOWABLE % DIFFERENCE FOR STEADY (FIFO Setup Tab) then the sample is
entered into the SECONDARY FIFO. If after many samples the SECONDARY FIFO
is full based on NUMBER OF POINTS IN FIFO (FIFO Setup Tab) and the %Dif of the
SECONDARY FIFO is lower than the ALLOWABLE % DIFFERENCE FOR
STEADY (FIFO Setup Tab) then the average of this FIFO is used to fill the PRIMARY
FIFO. This would sequence of events would happen whenever you switch to a resin
with a significantly different bulk density in the middle of a run without performing a
feeder calibration. Normally the SECONDARY FIFO is a means to collect a random
erroneous measurement without knocking the PRIMARY FIFO out of steady. This
allows you to use a significant number of points where in the older FIFO OL method
you would have trouble with a random nuisance event knocking the FIFO out of
steady.
• NOTE ON FIFO DATA PAGE. This page is normally not used and only comes in to
play when diagnosing a problem or to verify that a new installation was working
correctly.