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FC-21 Flow Computer
following:
1) Prompts the user for only critical information.
2) Automatically sets specifications to common uses.
After following the Quick Setup procedure, the unit will be operational to perform the basic
measurement. The setup can be further customized using the setup menus.
Quick Update %
This feature is used to disable the rate averaging filter when a significant change in the flow rate occurs.
The user can enter the percent of change needed to be detected to disable the averaging feature. This is
especially useful during start-up and shutdown of flow.
Rate Averaging Filter
The rate averaging filter is used to stabilize fluctuating rate displays. Higher settings provide more
averaging for a more stable display. Derived from the equation:
(OLD DATA x "Avg. Filter" + NEW DATA)
("Avg. Filter" + 1)
Ratemeter
Any device used to display the speed of a process. The ratemeter in the FC-21 displays flow rate.
Ref. Dens.
Abbreviation for Reference Density. This is the fluid density at reference temperature.
Ref. Temp.
Abbreviation for Reference Temperature. This represents the base or reference condition to which
corrected flow will be computed.
Reset/Start Control Input
In a batching system, a single operator activation of the START key or Control Input 1 will reset the
total then start the batch process.
Single_Pulse
The Single_Pulse setting is used for flowmeters with single pulse outputs.
Slow Start Quantity
The Slow Start Quantity is a function that allows an amount to be entered for a Slow Start up. This
function requires two stage valve control. RLY 1 (slow flow) will energize for Slow Start and RLY 2 (fast
flow) will energize after the Slow Start Quantity has been delivered. This helps reduce turbulence when
filling an empty container.
Sqrt
Abbreviation for Square Root Extraction. Used for flow elements using differential pressure
measurements.
Stop/Reset Control Input
In a batching system, a single operator activation of the STOP key or Control Input 2 will stop the batch
process then reset the total.
Time Constant
A damping factor for an averaging filter for the analog output. (see also Rate Averaging Filter)
Totalizer
Any device which accumulates and displays a total count.
UVC
Abbreviation for Universal Viscosity Curve. A presentation of the combined flowrate/viscosity
calibration for a turbine flowmeter.
VFD
Abbreviation for Vacuum Fluorescent Display
Visc Coef
Abbreviation for Viscosity Coefficient. One or more coefficients in an equation used to describe the
viscosity as a function of temperature for a fluid.
Volume Flow
The measurement of volumetric flow.
12. Glossary Of Terms
(Continued)
