Owner manual

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 www.campbellsci.com/cws900

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)