molbox™ RFM™ OPERATION AND MAINTENANCE MANUAL
© 1998-2007 DH Instruments, a Fluke Company
Page 162
Rate
A DISPLAY function in which the current rate of change of the flow in flow units/second is
displayed. A measure of stability of the flow. See also Stability Limit.
Ready/Not Ready
Indication of when flow is stable within the stability limit and below the flow Reynolds
number limit. See also Stability Limit.
Reynolds Number
A ratio of the inertia forces to the viscous forces in a flowing fluid. This dimensionless
number, which is dependent on fluid viscosity, density, velocity and length of the flow field,
is often used to predict a boundary point between laminar and turbulent flow regimes.
RPT
Reference Pressure Transducer. The pressure transducers used in molbox RFM are
referred to as RPTs.
Single P Calibration
A molbloc calibration option for gases other than N2 which is valid at a single specified
operating pressure.
Stability Limit
A limit expressed in units of flow per second (e.g., sccm/second). The stability limit is used
as the
Ready/Not Ready
criterion
Ready (<*>)
if rate is less than stability limit,
Not Ready
(<
↑
> or <
↓
>) if rate is greater than stability limit. See also Rate.
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.
Target
The value from which deviations are measured in the DEVIATION DISPLAY function.
Test Gas
The gas flowing through the molbloc that is being used to run the test or calibration. The
test gas, from the standpoint of the device under test, could be a surrogate gas or the
process gas.
Totalize
A DISPLAY function in which the total mass or volume flowed over a period of time is
accumulated.
Upstream
Location of point A relative to point B in a flow system in which point A is at a different
location in the opposite direction of the flow. For example, the upstream molbloc pressure
port is upstream relative to the downstream pressure port because it is at a different
location from the downstream port in the opposite direction of the flow.
User Level
Level of security that can be set to prevent access to certain molbox RFM functions.
User Mass Flow Units
Volumetrically based mass flow units of measure with a user set reference temperature.
venturi nozzle
A flow orifice using a specific shape characterized by a convergent and divergent section,
used to define flow measurements by measurement of flow conditions and gas properties.
A critical flow venturi nozzle is a venturi nozzle used to define flows within the critical flow
regime.
Volume Flow Pressure
The absolute pressure of the flowing gas at the device under test for volume flow units of
measure.
Volume Flow
Temperature
The temperature of the flowing gas at the device under test for volume flow units of
measure.
Volume Flow Units
Units of measure of volume flow.
Содержание molbox RFM
Страница 10: ...molbox RFM OPERATION AND MAINTENANCE MANUAL 1998 2007 DH Instruments a Fluke Company Page VIII N NO OT TE ES S ...
Страница 142: ...molbox RFM OPERATION AND MAINTENANCE MANUAL 1998 2007 DH Instruments a Fluke Company Page 132 N NO OT TE ES S ...
Страница 158: ...molbox RFM OPERATION AND MAINTENANCE MANUAL 1998 2007 DH Instruments a Fluke Company Page 148 N NO OT TE ES S ...
Страница 164: ...molbox RFM OPERATION AND MAINTENANCE MANUAL 1998 2007 DH Instruments a Fluke Company Page 154 N NO OT TE ES S ...
Страница 170: ...molbox RFM OPERATION AND MAINTENANCE MANUAL 1998 2007 DH Instruments a Fluke Company Page 160 N NO OT TE ES S ...