Fluke MOLBOX RFM Operation And Maintenance Manual page 172

molbox™ RFM™ OPERATION AND MAINTENANCE MANUAL
Rate
Ready/Not Ready
Reynolds Number
RPT
Single P Calibration
Stability Limit
Surrogate Gas
Target
Test Gas
Totalize
Upstream
User Level
User Mass Flow Units
venturi nozzle
Volume Flow Pressure
Volume Flow
Temperature
Volume Flow Units
© 1998-2007 DH Instruments, a Fluke Company
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.
Indication of when flow is stable within the stability limit and below the flow Reynolds
number limit. See also Stability Limit.
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.
Reference Pressure Transducer.
referred to as RPTs.
A molbloc calibration option for gases other than N2 which is valid at a single specified
operating pressure.
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.
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.
The value from which deviations are measured in the DEVIATION DISPLAY function.
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.
A DISPLAY function in which the total mass or volume flowed over a period of time is
accumulated.
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.
Level of security that can be set to prevent access to certain molbox RFM functions.
Volumetrically based mass flow units of measure with a user set reference temperature.
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.
The absolute pressure of the flowing gas at the device under test for volume flow units of
measure.
The temperature of the flowing gas at the device under test for volume flow units of
measure.
Units of measure of volume flow.
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The pressure transducers used in molbox RFM are