TDR SOIL MOISTURE MEASUREMENTS
5
FIGURE 3-4. SDM Wiring
3.3.2 PS1502B
The PS1502B has three connections to the
datalogger: +12, Ground, and a control input
which allows the datalogger to switch the power
to the 1502B. In the example program
(Section 5), the control input is connected to
control port 4.
3.4. SOIL PROBES
The PB30 consists of two 30 centimeter
stainless rods and a twinlead cable. The
probes are shipped without the cable attached.
The rods are attached with the supplied screw
and star washer (Figure 3-5).
The two rods of the probe are pressed into the
soil with the rods parallel. The cable leads allow
the common 5 centimeter rod spacing.
The cable on the probe has a BNC connector
that connects directly to the SDMX50.
FIGURE 3-5. PB30 Assembly
