Changing the sensor – Vaisala HMT310 User Manual
Page 66
User's Guide _______________________________________________________________________
66 ___________________________________________________________________ M210619EN-E
When replacing the filter, wear clean gloves to avoid depositing dirt or
oil on the filter.
Replace the filter as follows:
1.
Turn the filter counterclockwise until it is loose.
2.
Pull the filter straight out carefully. Do not damage the sensor.
3.
Take the new filter, and insert it to the filter thread.
4.
Tighten the new filter to 5 Nm by turning it clockwise.
Changing the Sensor
NOTE
When replacing the sensor, the new sensor must be of the same type as
the old sensor (for example, HUMICAP180R). The sensor type can only
be changed at a Vaisala Service Center. Information on Vaisala sensors
is available online a
Changing HUMICAP180 and HUMICAP180R humidity sensors is
simple. If the transmitter has the chemical purge and/or warmed probe
option which utilizes the HUMICAP180C or HUMICAP180RC sensor,
the change is more difficult as soldering is required to attach the pins of
the integrated temperature sensor element. Vaisala recommends that you
leave the replacement of HUMICAP180C and HUMICAP180RC sensors
to Vaisala Service Centers, but spare parts are available if you want do it
yourself. Soldering instructions are not provided.
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 Maintenance on page 65.
1.
Remove the filter from the probe. See the instructions in section
Changing the Filter on page 65.
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 Calibration after Sensor Change on page 71.
4.
Attach a new filter on the probe. When using the stainless steel
filter, take care to tighten the filter properly (recommended force
5 Nm).