MOLSTIC-S™ OPERATION AND MAINTENANCE MANUAL
© 2004-2007 DH Instruments, a Fluke Company
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20
2.4
MOLSTIC-S INTERCONNECTIONS
2.4.1
GAS SUPPLY CONNECTIONS TO MOLSTIC-S
Determine the maximum operating pressure range of your molbox RPTs prior to connecting a
gas source to your molstic-S.
See the molbox calibration report to determine the pressure range of the Reference
Pressure Transducers (RPTs) in the molbox you are using. molbox1-A700K has a maximum
operating pressure of 600 kPaa (87 psia), and molbox1-A350K has a maximum operating
pressure of 250 kPaa (36 psia).
If a contaminated device under test is located upstream of the molbloc, contaminants
may flow from the device under test to the molbloc-S and alter its calibration. If the
device under test must be connected upstream of the molbloc-S, be sure it is clean before
flowing and consider installing a filter between the DUT and the molbloc.
The gas supply to the molstic-S has the following requirements:
•
The gas supply must be clean and free of particulate contamination in order to avoid
damage to the molbloc.
•
For correct measurements, the gas must be of the same species as that selected by the
molbox
[GAS]
function. Use of ambient air (moist air) is supported by the molbox. Gas purity
will affect the measurement uncertainty of the flow measurements as molbox uses the
thermodynamic properties of the flowing gas in its calculations. Use gases with purity of
99.9 % or better for molbloc measurements.
•
The pressure must be regulated and stable within the limits of the molbloc-S calibration
pressure range, and low enough to avoid over-pressurization of the molbox.
•
The pressure must not exceed the maximum operating pressure rating of the RPTs in
the molbox.
See the back panel label of the molbox to determine the maximum
operating pressure allowed. Verification of the pressure rating should be obtained
by examination of the calibration range on the molbox certification of calibration.
