Unit] - Fluke MOLBOX1 PLUS - V 6.00 Operation And Maintenance Manual

MOLBOX1+™/MOLBOX1+S, MOLBLOC TERMINAL OPERATION AND MAINTENANCE MANUAL
3.4.3

[UNIT]

 PURPOSE
To specify the flow unit of measure in which molbox1+ displays measured flow values.
 PRINCIPLE
molbox1+ calculates the mass flow of various gases in kilograms/second [kg/s]. molbox1+
also supports conversions to a variety of other flow units of measure. The UNIT function
allows the flow unit of measure in which molbox1+ displays measured flow to be selected. These
include units of mass flow, including volumetrically based mass flow units (i.e., sccm) as well
as units of volume flow (i.e., ccm). See Table 29 for a complete listing of the unit conversions
available. molbox1+ can also display the measured flow in two different units of measure
simultaneously (see Section 3.4.6.5).
 OPERATION
If the molbox1+ is equipped with the optional MFC control function (see Section 3.4.8), the unit of
measure for the molbox1+ flow display may be defined by the currently selected MFC profile. In that
case, the [UNIT] function key is used to select the MFC output display unit (see Section 3.4.8.3).
•
If an MFC profile other than profile #1 or #2 is active, the unit of measure is the unit of
measure selected in the MFC profile. If the MFC control function is not present, or is
turned OFF, or MFC profile #1 or #2 is selected, the [UNIT] function key allows direct
selection of molbox1+ flow display units as described below.
•
From the main run screen, press [UNIT]:
The display is:
Select the desired unit. For all units except <uxxx> or <vlm>, operation then returns to the run
screen with the flow unit of measure changed to the selected unit. When user units (i.e., uxxx)
are selected, the reference temperature must be specified before the unit is activated (see
Section 3.4.3.3).
accessed. The desired volume unit must be selected and then the temperature and pressure
of the flowing gas must be specified (see Section 3.4.3.4).
•
If the MFC Control option is active and the MFC profile selected is NOT #1
or #2 (see Section 3.4.8), the molbox1+ flow unit is automatically the unit
specified in the current MFC profile (see Section 3.4.8 and 3.5.5) and the
UNIT function controls the unit used for displays of MFC set and measure
values.
•
See Section 7.1.3 for specific molbox1+ flow unit conversion calculations.
•
molbox1+ supports many more flow units of measure than the six default
units of the UNIT function. The six units available under the UNIT function
can be customized to include any molbox1+ supported units in any order
(see Section 3.5.8).
© 1995 - 2010 Fluke Corporation, DH Instruments Division
The gas selected on the molbox1+ should always be the gas
that is flowing through the molbloc. molbloc/molbox does not
use K factors or gas conversion factors between gases. When
calibrating or testing a device with a surrogate gas, molbox1+
should be set to the surrogate gas.
conversion factor, if used, defines the relationship between the
surrogate gas and the process gas for the device being tested,
not for molbox1+ (see Section 3.4.1, PRINCIPLE). The K factor
is supplied by the manufacturer of the device being tested.
When "vlm" (volume) units are selected, a menu of volume units is
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Note
The K factor or gas
1sccm 2slm 3uccm
4pccm 5mg/s 6vlm
Note