Michell Instruments MDM50-HP, Руководство пользователя

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MDM50 HP Version User’s Manual
4 97478 Issue 1.4, October 2019
OPERATION
3 OPERATION
!
Maximum operating pressure is 300 barg (4350 psig).
It is important that the gas fittings are correctly tightened, and
any tubing is secure in the push fittings before use.
Failure to do so will affect the instrument's pressure rating.
3.1 General Operation
To operate the MDM50-HP, follow these instructions:
1. Ensure that both the gas fittings and the Swagelok
®
tube fittings are fully
tightened before use.
2. For measurement at line pressure, connect the supplied metering valve to
the outlet of the instrument. For measurement at atmospheric pressure,
connect the metering valve to the inlet.
3. Gas under test should be restricted to flow rates between 1 and 5 Nl/
min (2 and 10.6 scfh) and pressures from atmospheric to 300 barg (4350
psig).
4. Connect the sample gas supply line to the instrument Gas In port.
5. Connect the sample gas vent line to the instrument
Gas Out
port.
6. Switch the instrument on. The display will begin to change as the sensor
responds to the applied dew point.
7. Allow the gas to flow until the display shows a stable reading. Typically
this would be around 15 to 30 minutes for spot checks at dew points of
-40°C (-40°F) and above.
8. Switch the unit off and disconnect the sample lines.
!
Before disconnecting the MDM50-HP from the gas line it
is essential to vent the system to atmospheric pressure,
otherwise severe injury could result.
NOTE: Filters are essential for potentially dirty/contaminated gases – the
fitted filter should be checked before and after use and replaced regularly - as
required.
NOTE: This High Pressure version features two gas fittings with 4mm orifices
that give no restriction and are engraved with a number 1. Atmospheric or
line pressure measurement is achieved by changing the positioning of the
metering valve as per the General Operation instructions above.