Vaisala Drycap DMT152, Руководство пользователя

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4. Installation
4.1 Selecting the Location
It is important that the conditions at the point of installation represent well the gas to be
measured. Temperature changes do not affect the dew point measurement, but pressure
changes will have an effect on the measurement. All leaks in the system must be eliminated to
avoid ambient humidity affecting the measurement.
Direct installation to the measured gas is the recommended installation method if the
temperature of the gas is suitable for DMT152 and no additional filtering is needed due to very
dusty or oily gas. Oil as such is not harmful for the DRYCAP sensor, but response time may be
slower if there are oil particles in the system, or if oil is collected to the filter over a longer
period of time. The maximum measurement pressure is 50 bar
a
/ 725 psi
a
(absolute pressure)
for direct measurement.
If the gas temperature is higher than the specified maximum operating temperature of the
transmitter, gas sampling and cooling it to ambient temperature (for example, 10 °C / 18 °F) is
recommended. Note that the dew point temperature must be clearly lower than the ambient
temperature to avoid condensation in the sampling line. Sampling from the process is easy by
using Vaisala sampling cell options; see
Sampling Accessories (page 21) .
DMT152 is light in weight, which means that it can be installed in a sample pipeline in the
sampling cells without the need for any additional mechanical support.
4.2 Installing the Transmitter
Figure 2 DMT152 Installed Directly to Pipeline (Max. 50 bar)
Chapter 4 – Installation
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