Vaisala DMT340 - Manual (Page 151)

Chapter 6 _______________________________________________________________ Maintenance
VAISALA _______________________________________________________________________ 149
CHAPTER 6
MAINTENANCE
Periodic Maintenance
Cleaning
Clean the transmitter enclosure with a soft, lint-free cloth moistened with
mild detergent.
Changing the Probe Filter
NOTE Some probe and filter combinations are equipped with a washer under the
filter. The purpose of the washer is to prevent vibration from loosening
the filter. If the washer is present, leave it in place when changing the
filter.
1. Turn the filter counter-clockwise to loosen it.
2. Remove the filter from the probe. Be careful not to touch the sensor
with the filter. Without the filter in place, the sensor is easily
damaged – handle the probe carefully.
3. Install a new filter on the probe. When using the stainless steel
filter, take care to tighten the filter properly (recommended
force 5 Nm).
New filters can be ordered from Vaisala, see Available Options and
Accessories Table 35 on page 170.
Calibration and Adjustment
The DMT340 is fully calibrated and adjusted as shipped from factory.
Typical calibration interval is two years. Depending on the application it
may be good to make more frequent checks. Calibration must be done
always when there is a reason to believe that the device is not within the
accuracy specifications.
It is recommended that calibration and adjustment should be carried out
in a Vaisala Service Center. For contact information of Vaisala Service
Centers, see
www.vaisala.com/servicecenters .