Vaisala MMT330 - Manual (Page 136)

User's Guide _______________________________________________________________________
136 __________________________________________________________________ M210764EN-F
Changing the Sensor
The user can change HUMICAP® 180L2 sensors. Changing the sensor
should be considered corrective maintenance, and it is not necessary in
normal operation. If the accuracy of the transmitter does not seem to be
within specification, it is more likely that the transmitter is in need of
calibration and adjustment, and not sensor replacement. Refer to chapter
Calibration and Adjustment on page 141.
1. Remove the filter from the probe. See the instructions in section
Changing the Probe Filter on page 135.
2. Remove the damaged sensor and insert a new one. Handle the new
sensor by the plastic socket. DO NOT TOUCH THE SENSOR
PLATE.
3. Perform a calibration and adjustment as instructed in section
Relative Humidity Adjustment after Sensor Change on page 146.
4. Install a new filter on the probe. When using the stainless steel
filter, take care to tighten the filter properly (recommended force 5
Nm).
0508-079
Figure 67 Changing the Sensor
The following numbers refer to Figure 67 above:
1 = Pull out the sensor
2 = Plastic socket