Vaisala Drycap DMT152, User Manual

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The DSC74B limits the flow rate with a fixed leak screw. The flow is optimized for pressures 3 ...
10 barg. The fixed leak screw eliminates the risk of opening the leak screw fully by accident
and this way emptying a gas vessel. The maximum flow can be increased, if needed, by
removing the leak screw and adjusting the flow manually with the valve. Harmful gases can be
recovered by connecting a collection system at the outlet (not available from Vaisala).
In the basic operation of the DSC74B, the gas flows to the sensor from the front and the outlet
is on the side. To have the measurement done at atmospheric pressure, the inlet and outlet are
reversed. Then the reducing parts supplied (G3/8" - G1/2" or G3/8" - G1/4") on the outlet side
help to protect the sensor from ambient humidity coming in.
DSC74B parts are:
• Sampling cell, thread G3/8"
• Connection part with a needle valve and an integrated leak screw
• Reducing Nipple (thread adapter), G3/8" - G1/2"
• Reducing Adapter (thread adapter), G3/8" - G1/4"
1
2
Figure 10 DSC74B
1 Gas goes in
2 Gas comes out
DMT152 User Guide M210865EN-J
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