Soil moisture - capacitance (TMS)

Parameter to be measured:

Soil moisture, soil temperature

Method:

Capacitance

Equipment:

temperature measurement with sensor MAXIM/DALLAS Semiconductor DS7505U+, with resolution of 0.0625 °C and with accuracy of ±0.5 °C

soil moisture measurement based on capacity technique in the frequency of 100-200MHz

integrated data loggers of 32MBit

Advantages:

• cheap
• Easy to install

Disadvantages:

• Calibration needed
• Small measurement volume compared to other sensors
• not for portable usage designed
• life time is short (in the first two years errors of the measured values start to increase, especially the temperature sensor is effected)

What to watch out for:

• Careful installation, air gaps have a sustainable influence on the measurement compared to other sensors because of the small measurement volume

Links

Projects that used the above equipment:

• TERENO

Other related web sites:

• [1]