Monitoring and Recording Soil Moisture Using Wireless Data Collection

Wireless Voltage Data Logger Records in Real-Time

CAS DataLoggers recently provided the low cost wireless solution for a government organization undertaking an environmental project for recording and remotely monitoring the moisture content of peat moss soil. The data would be used in support of developing climate prediction efforts, so real-time viewing was a must. The project also required convenient data collection so users wouldn’t have to travel to each recorder across the tracts of soil to gather the data.

Project staffers installed 3 RVR-52A Wireless Voltage Data Loggers among the 3 fields under study. The monitors provided Voltage Pulse or Event Measurement (0 - 6.5V), logging readings as a direct percentage. CAS DataLoggers also provided an optional soil moisture sensor with each logger. These probes monitored the surrounding soil moisture with an accuracy of ±3% at a range of 0 to Volumetric Saturation, providing a voltage output directly proportional to the soil’s volumetric water content. Designed for permanent, long term monitoring, the vertical probes could be installed at any depth in the soil profile, enabling different placements.

Completely self-contained, with no external power source requirements, the waterproof data loggers and sensors were deployed directly in the field and stood up to exposure to the rainy conditions. Each logger’s clear LCD showed all current values and Upper & Lower limit settings, storing 16,000 data points at a user-settable sample rate of from once a second up to once an hour.

Additionally, a Handheld RTR-57U Data Collector was also provided to wirelessly monitor and download all the recorded data from the wireless data loggers. This portable, battery powered device was ideal for collecting data in the fields, since running wires and cables were not an option. This data was displayed in both graphical format on the device and uploaded to a PC via a USB connection. Using the real-time monitoring mode and the remote search function, users collected the data from a 100 meter range, storing as many as 256,000 readings. If the project needed to be expanded, users could register up to 60 groups of 64 loggers each.

The wireless system offered convenient functionality at a very affordable price, providing a flexible solution for the project. Other options available with this system included models to monitor and record air temperature, relative humidity, and soil temperature, all with the same wireless system. An extended battery version was also an option to provide up to 2 ½ years of operation.