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Dsc74b two-pressure sampling cell – Vaisala DMT132 User Manual

Page 29

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Chapter 3 _______________________________________________________________ Installation

VAISALA _______________________________________________________________________ 27

When using the DSC74, seal the threads of the quick connector or thread
adapter carefully with PTFE thread seal tape. Tighten with an open-end
wrench.

0507-105

Figure 17

DSC74 Sampling Cell with Accessories

where

1

=

Thread adapter type G3/8" - G1/2"

2

=

Thread adapter type G3/8" - G1/4"

3 = Quick

connector

4 = Leak

screw

5

=

Sampling cell body (DMT242SC)

DSC74B Two-Pressure Sampling Cell

The DSC74B and DSC74C sampling cells are enhanced versions of the
DSC74. The body is designed in a way that it is possible to measure at
both system pressure and atmospheric pressure.

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