User guide

AccuMeter Controller Chapter 11: Configuring a new PLC 78
FIFO SETUP Tab
• SAMPLE TIME ONCE IN STEADY WINDOW. Once the blender achieves “In
Steady Window” then it begins to calculate the extrusion process rate at this sample
interval. Setting this value too fast can add error to the process rate data. Default is 10
seconds.
• NUMBER OF POINTS IN FIFO. Number of samples based on above interval that are
analyzed by the FIFO algorithm. Increasing this value can smooth out the result.
• ALLOWABLE % DIFFERENCE FOR STEADY. If the percent difference of all
samples in the FIFO are within this tolerance then the FIFO is considered steady. If
this value is set too small then you may never get a steady flag for the blender and
therefore will not get a process rate. If it is set too large then you may have unwanted
error in the calculated process rate.
• MAX ALLOWED BLEND RATE. This serves 2 functions. It prevents erroneous
process rate calculations caused by an operator draining the blender without shutting it
off first and it also prevents the blender from running at a rate higher than this value.
This is useful if you have augers that cannot run low enough to match the rate. You
can set this to a value just above the true process rate and therefore the augers will run
for a long time before shutting off. You should order the correct augers to get the
blender to lock into the process rate.
• TIME REQUIRED IN STEADY WINDOW FOR STEADY WTP FLAG. The blender
must be able to stay in the steady window on the mass flow hopper for this amount of
time before it is considered stable. Decreasing this value may cause unwanted error in
the calculation.