Temperature/RH Smart Sensor (S-THB-M00x) Manual
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11427-M MAN-S-THB
Mounting
Typical Mounting
Solar Radiation Shield: Use
the washer and screw
(included with the M-RSA
radiation shield) or cable
clamps (included with the
RS3-B radiation shield) to
secure the smart sensor in
the radiation shield as shown
at right and below.
Temp/RH Sensor mounted in the
Solar Radiation Shield M-RSA
Temp/RH Sensor mounted in
Solar Radiation Shield RS3-B (cross-section)
Mounting Considerations
•
A solar radiation shield is strongly recommended when
measuring air temperature in direct sunlight. Solar radiation
can be a significant source of error in the temperature and
RH readings.
•
When mounting the probe, care should be taken to thermally
isolate the sensor from the mounting surface to ensure
accurate air temperature and humidity readings. The probe’s
temperature sensor is at the end of the cable, just below the
cup.
•
It is recommended that the probe be protected from direct
exposure to the weather. This will prolong the sensor
accuracy.
•
If you are running sensor cables along the ground, it is
recommended that you use conduit to protect against
animals, lawn mowers, exposure to chemicals, and so on.
•
To provide long-term protection from moisture entry, the
smart sensor adapter must be mounted horizontally and with
the cable wires routed with drip loops so that water drains
away from the cable entry point as shown in the next
column. When mounted properly, the housing is
weatherproof (but not waterproof).
•
Refer to the station manual and Tripod Setup Guide for more
information regarding setting up stations.
Connecting the Sensor to a Station or Logger
To connect the sensor to a station or logger, stop the station or
logger from logging and insert the smart sensor’s modular jack
into an available smart sensor port. See the station manual for
details on operating stations or loggers with smart sensors.
Replacing the RH Sensor
The RH sensor is protected by an ASA styrene polymer cap and
a modified hydrophobic polyethersulfone fluid barrier
membrane that allows vapor to penetrate while protecting the
sensor from condensation. RH sensor performance may
degrade over time. To replace the RH sensor, take the following
steps:
1.
Remove the tape fastening the sensor cap to the receptacle.
Discard the tape.
2.
Grasp the cap and membrane and pull firmly to remove
them. Discard them.
3.
Note the orientation of the small circuit board containing
the RH sensor
.
Pull it out and discard it in compliance with
local disposal guidelines for circuit boards.
4.
Push gently but firmly to install the new sensor (HUM-
RHPCB-2)
in the same orientation.
5.
Put the new sensor cap and membrane on. Do not force the
cap. If it does not go on easily, the sensor may be installed
backwards. Reverse the sensor and try again.
Maintenance
The temperature/RH smart sensor is sensitive to dust, salts and
other airborne contamination. Periodically inspect the RH
sensor. If contamination is present on the protective cap, gently
rinse it with cool fresh water. If the sensor itself is
contaminated, you can rinse it with distilled water. Do not use
hot water, organic solvents, or detergents. Dry before use.
Drip loop
Smart
sensor
adapter
mounted
horizontally
Drip
loop
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