Cosa-xentaur Xentaur XPDM Manuel d'utilisateur télécharger pdf (Page 6)

page 3

3. Principle of Operation

Dewpoint sensors, like all hygroscopic materials, adsorb much faster than they desorb.

Therefore, an accurate measurement will be obtained much faster, if at the beginning of

the measurement, the sensor is at a dewpoint drier than the gas to be measured. The

XPDM design allows the sensor to be moved directly between dry-storage and the sample

cell, without any exposure to ambient air.

Sensor in Sensor In

dry-storage position measuring position

1. Sample Gas In 7. Sensor Actuator

2. Sample Gas Out 8. Desiccant Chamber

3. Piston 9. Filter Mesh

4. Sample Cell 10.Electronic Board

5. Sensor 11.Instrument Case

6. Spring loaded PTFE seals

The drawing on the left shows the XPDM with the sensor in dry-storage position. The sen-

sor is enclosed in a gas-tight container and surrounded by desiccant. The sample gas

passes through the sample chamber and prepares the environment for measurement.

Blocking of the outlet port will pressurize the sample chamber and move the piston into

the position shown on the right. The sensor is now exposed to the sample gas without ever

having been exposed to ambient air. After the measurement is taken, pushing in the sen-

sor actuator will return the sensor into dry-storage, where it will dry down and ready itself

for another fast measurement.

2 2

1 1

1111

1 2 3 4 5 6 7 8 9 10 11 ... 23 24

Pas de commentaire

Cosa-xentaur Xentaur XPDM Manuel d'utilisateur Page 6