DH Instruments MFC-CB, Руководство по эксплуатации и обслуживанию

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MFC-CB™ Operation and Maintenance Manual
©2001~2007 DH Instruments, a Fluke Company
Page 94
7.4 GLOSSARY
A (
adder
) A value that is added to a set point or measurement to offset the value.
Clean A DISPLAY function in which the second line of the display is blank (clean)
except for the active channel indicator.
DEV1&2 A DISPLAY function in which DEVICE 1 and DEVICE 2 are displayed
simultaneously. DEVICE 1 set point and measurement are on the top line and
DEVICE 2 set point and measurement are on the bottom line.
DEVICE 1, DEVICE 2 The two MFC-CB device channels on which analog signals can be output and
measured.
Device Channel MFC-CB’s two analog output/input channels are referred to as device channels
(DEV1, DEV2).
Dif (Difference) A DISPLAY function in which the difference between the measurement of the
inactive device channel and the active device channel is displayed (inactive – active).
FS Abbreviation of “full scale”. The full scale value is the maximum value or the span of
a measurement range. Limits and specifications are often expressed as %FS.
K Factor A factor representing the relationship between the process gas and a surrogate gas
for an MFC pr MFM.
M (
multiplier
) A value by which a setpoint or measurement is multiplied to change the slope of
the set points or readings.
MFC Acronym for mass flow controller, a device that sets flows in response to
electrical set points.
MFC Profile An MFC-CB on-board file that defines the electrical and corresponding flow
range in which a device channel should operate.
MFM Acronym for mass flow meter, a device that measures flow and outputs a
proportional electrical signal.
Ratio
A DISPLAY function in which the ratio of the measurement on the inactive
device channel and the active device channel is displayed (inactive/ active).
Set point An analog signal sent to an MFC to cause it to set a flow.
Sum A DISPLAY function in which the sum of the measurement on device channel 1
and device channel 2 is displayed.
Surrogate Gas
A gas whose behavior, from the standpoint of a device under test, is similar to
the process gas for which the device is to be characterized and used. A
surrogate gas is often used in calibration and testing when the process gas
cannot be used for safety or cost reasons.
User Level Level of security that can be set to prevent access to certain MFC-CB functions.