5
2. Precautions
. • Warranty limitation: The XPDM’s sample cell/piston assembly should not be disas-
sembled except by factory trained personnel. The warranty is voided, if the sample
cell piston assembly is disassembled by the customer.
• Avoid contaminated sample streams: The XPDM has been designed to allow for
fast and precise measurements of dewpoints as low as -100 °C. Therefore, all
surfaces in contact with the sample stream are made from electropolished
stainless steel. This minimizes the time for the instrument to reach equilibrium with
the sample stream, thus speeding up the measurement. The introduction of
corrosive gases or gases contaminated with oils, solvents etc. may damage or coat
the electropolished surfaces and slow down the measurement. Surfaces
contaminated with oils etc. can be cleaned by factory trained personnel (please
contact your sales representative). Surfaces damaged by corrosive gases are
damaged permanently, causing longer response times. Gases containing chlorine,
ammonia, HCl or SO
2
may also cause
damage to the sensor. SO
2
can be monitored when the moisture content is low.
. • Avoid liquid water: Avoid the introduction of liquid water into the sample cell, as this
may damage the sensor. Do not breathe directly into the instruments sample ports,
as condensation may form which could damage the sensor element. If liquid water
can not be avoided, order the XTR-65W sensor which is water proof, but has a
limited range, and a slower dry down response.
. • Avoid high pressure: The XPDM has been designed for operation at pressures
slightly above atmospheric, however each sample cell, sensor, piston, dry-storage
assembly has been tested for pressures up to 120 PSI. Do not introduce sample
streams, which could cause pressure rises above 100 PSI. Make your
measurements at atmospheric pressures, and use the pressure calculation feature
to calculate dew-points at higher pressures. Ask your representative for a regulator
installation kit.
. • Exercise Caution with Hazardous Gases: Please use appropriate precautions if the
sample you are about to measure is hazardous. Place the unit in a safe area, if it is
to be used with hazardous gases. Please be aware that the possibility of a small
leak always exists. Such a leak will not influence the accuracy of the measurement,
but may represent a risk if the sample gas is of hazardous nature.
. • Avoid Extreme temperatures: Do not install the unit near heat sources such as
radiators or air ducts. The instruments’ operating temperature range is -10°C to
50°C.
. • Avoid Mechanical Vibration: Do not install the unit in places subject to extreme
mechanical vibration or shock. Use resilient mounting, if shock and vibration are
not avoidable. Call your representative if in doubt.
. • Avoid long exposures of sensor element to room air: For reasons explained later in
this manual (section 7), do not expose the sensor to room air for longer then
necessary (1 - 2 Minutes). The sensor is exposed to room air, when the sensor
actuator is in the out position and no sample line is connected, or the sample gas is
shut off. It is best to push the sensor back into dry-storage, after a measurement is
completed and whenever the instrument is not in use.
. • Do not force the Actuator: Remove any port obstructions (such as shipping caps)
before operating the Actuator.
Содержание XPDM
Страница 21: ...21 Apendix A Flow Diagram of User Interface in Operating State ...
Страница 22: ...22 Appendix B Flow Diagram of User Interface in Setup State ...
Страница 23: ...23 ...
Страница 25: ...25 Appendix D Uncertainty in LBS and PPMV calculations ...