Campbell HMP60, Руководство по эксплуатации продукта

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NOTE:
When the probe is connected to a CS110 Electric Field Meter, the probe is measured by the
CS110 internal CR1000 data logger module using
VoltSE() instructions. Relative humidity
and temperature signals are measured on single-ended terminals 1 and 2, respectively.
250 µs integration should be used in the
VoltSE()
instructions.
7.3 Mounting
Sensors should be located 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.
Standard measurement heights:
1.5 m (AASC)
1.25 to 2.0 m (WMO)
2.0 m (EPA)
See Attributions and References (p. 15) for a list of references that discuss temperature and
relative humidity sensors.
When used in the field, the HMP60 must be housed inside a solar radiation shield. Typically, the
41303-5A or RAD06 6-plate solar radiation shield is used. The HMP60 is held within the 41303-5A
by a mounting clamp (
FIGURE 7-2 (p. 9)).
This probe may also be housed in a 41003-5 or RAD10 10-plate shield. Additional hardware must
be used with the 41003-5. No additional hardware is required with the RAD10. A 10-plate shield
adapter allows the HMP60 to be mounted in the lower part of the 41003-5 shield.
The white color of these shields reflects solar radiation, and the louvered construction allows air
to pass freely through, thereby keeping the probe at or near ambient temperature. The RAD06
and RAD10 use a double-louvered design that offers improved sensor protection from insect
intrusion and driving rain and snow. In addition, the RAD06 and RAD10 shields have lower self-
heating in bright sunlight combined with higher temperatures (> 24 °C (75 °F)) and low wind
speeds (< 2 m/s (4.5 mph)), giving a better measurement.
Each of these solar radiation shields attaches to a crossarm, mast, or user-supplied pipe with a 2.5
to 5.3 cm (1.0 to 2.1 in) outer diameter.
HMP60 Temperature and Relative Humidity Probe 8