Campbell Scientific CS215 Temperature and Relative Humidity Probe - Manual (Page 18)

CS215 Temperature and Relative Humidity Probe
7.3 Installation
Locate the sensor over an open, level area at least 9 m (EPA) in diameter. The
surface should be covered by short grass or the natural earth surface where
grass does not grow. Sensors should be located at a distance of at least four
times the height of any nearby obstruction and at least 30 m (EPA) from large
paved areas. Sensors should be protected from thermal radiation and
adequately ventilated. Protect the filter at the top of the sensor from exposure
to liquid water. The hydrophobic nature of the filter repels light rain, but
driving rain can force itself into the pore structure of the filter and take time to
dry out.
Standard measurement heights:
• 1.5 m (AASC)
• 1.25 – 2.0 m (WMO)
• 2.0 m (EPA)
See Section 10, Attributions and References, for a list of references that discuss
temperature and relative humidity sensors.
When used in the field, the CS215 must be housed in a radiation shield.
Typically, the 41303-5A six-plate solar radiation shield is used. The white
color reflects solar radiation, and the louvered construction allows air to pass
freely through, thereby keeping the probe at or near ambient temperature.
The 41303-5A attaches to a crossarm, mast, or user-supplied pipe with a 2.5 to
5.3 cm (1.0 to 2.1 inch) outer diameter.
A 41003-5 ten-plate solar radiation shield can also house the CS215 sensor by
using the 18.5 adapter (pn 6637). For this shield, tighten the sensor grip
around the probe where it best matches the size of the grip. (The probe will
also fit directly into most of the R.M. Young shields, where the probe enters
the shield from the top, pointing downwards.)
Both the 41303-5A and the 41003-5 solar radiation shields attach to a
crossarm, mast, or user-supplied pipe with a 2.5 to 5.3 cm (1.0 to 2.1 inch)
outer diameter.
Tools required for installing a radiation shield to a tripod or tower include:
• 1/2-inch open-end wrench
• small screwdriver provided with datalogger
• small Phillips screwdriver
• UV-resistant cable ties
• small pair of diagonal-cutting pliers
1. Loosen the plastic split collar at the base of the shield (reversing the
removable portion if necessary) and gently insert the probe.
2. Tighten the collar until it lightly grips the probe body.
3. Continue to push the probe up into the body of the shield until the step in
the tube stops it from going any further.
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