Model HFP01 Soil Heat Flux Plate
The HFP01’s output is in millivolts. To convert this measured voltage to heat
flux, it must be divided by the plate’s calibration constant. A unique
calibration constant is supplied with each sensor.
To get the soil heat flux at the surface, use at least two HFP01s to measure soil
heat flux at a depth of 8 cm; a TCAV Averaging Soil Thermocouple to
measure the temporal change in temperature of the soil layer above the HFP01;
and a CS616, CS650, or CS655 water content reflectometer to measure soil
water content (see Figure 6-1). The temporal change in soil temperature and
soil water content are used to compute the soil storage term.
The -L extension in the model name (i.e., HFP01-L) indicates a user-specified
cable length. This manual refers to the sensor as the HFP01.
The sensor's cable can terminate in:
•
Pigtails that connect directly to a Campbell Scientific datalogger
(option –PT).
•
Connector that attaches to a prewired enclosure (option –PW). Refer
to
www.campbellsci.com/prewired-enclosures
for more information.
•
Connector that attaches to a CWS900 Wireless Sensor Interface
(option –CWS). The CWS900 allows the probe to be used in a
wireless sensor network. Refer to
for
more information.
A general discussion about the characteristics and principles of
operation of heat flux sensors is shown in Appendix A.
NOTE
5. Specifications
Features:
•
Compatible with most of our contemporary and retired dataloggers
•
Compatible with the CWS900-series interfaces, allowing it to be used
in a wireless sensor network
Compatibility
Dataloggers:
CR800
series
CR1000
CR3000
CR5000
CR9000(X)
CR7X
CR510
CR10(X)
CR23X
21X
Operating Temperature:
-30
°
to +70
°
C
Plate Thickness:
5.0 mm (0.20 in)
Plate Diameter:
80.0 mm (3.15 in)
2
