Vaisala Drycap DMT152, User Manual

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6. Maintenance
6.1 Cleaning the Transmitter
The body of the transmitter can be cleaned by wiping with a moistened lint-free cloth. Do not
immerse the transmitter in liquid and do not use cleaning agents or solvents. Do not attempt
to clean the filter or the sensor element. If the filter is contaminated, replace it with a new one.
6.2 Changing the Filter
If the filter is contaminated, it should be replaced. New filters can be ordered from Vaisala
(order code 220957). Be careful when changing the filter, since it is easy to break the sensor
when the filter is removed.
If the transmitter is installed in a pressurized chamber, always make
sure that the pressure of the chamber is equalized with the ambient pressure
prior to removing the transmitter. When the transmitter is removed for
maintenance, cap the hole with a capped nut. This way, the process can be
running although the transmitter is not in place.
Plugs are available from Vaisala for ISO threaded connections (Vaisala order
code 218773) and NPT threaded connections (Vaisala order code 222507).
CAUTION!
1 2
3 4
Figure 16 Filter Structure
1 Vaisala DRYCAP sensor
2 Spring washer
3 Stainless steel mesh filter (do not touch)
4 Top of the filter
When replacing the filter, note the following:
• The pores of the steel mesh may become blocked if touched. Do not touch the filtering
surface with your hands or any tools. Always handle the filter from the top of the filter
body.
• Touching the filter with your fingers will also deposit oil and dirt on the filter, which may
affect the measurement. Always handle the filter with gloved hands.
Chapter 6 – Maintenance
53