The UMP-1 BTim is the compact version of the UMP-1 BT sensor. Measurement and transmission of the measured data are done via Bluetooth directly from, or on an Android smartphone, on which they are also stored. The necessary app can be downloaded in the Google Play Store and independently installed on any Android smartphone. As an option, we also offer an outdoor-ready smartphone with an already pre-installed app as part of our complete package. The representation of the data during the measurement can be done as a graph or as a measured value table.
The UMP-1 BTim consists of a shaft with integrated probe, height-adjustable handle, smartphone holder and spring guide for inserting the measuring rods. This device has all the advantages to be able to perform flexible and fast measurement campaigns with many individual measurements over a larger area. The measuring rods (antennas) have a larger diameter (5 mm) and are therefore more stable than those of the standard sensor. Under mechanical pressure, the measuring rods are pressed into the ground. The coil spring and a guide at the lower end of the shaft protect the rods from damage when piercing the ground. The shaft with handle and smartphone holder allows a quick work when performing the point measurements.
The shaft is made of stainless steel just like the measuring rods. The height-adjustable handle has non-slip plastic handles. The UMP-1 BTim is equipped with an integrated rechargeable battery that can be switched on and off for the measurement. The supply voltage is additionally detected. So the battery can be recharged in time to prevent data loss. The UMP-1 BTim has the following dimensions: height 970 mm, diameter 40 or 60 mm, width of the handle 405 mm.
The UMP-1 BTim determines the soil moisture by measuring the relative permittivity (permittivity, εr) of the soil. In addition, the electrical conductivity (mS / cm) can also be measured. The latter is determined by an additional circuit independent of the soil moisture. Since the relative permittivity is salt-dependent, excessively high conductivities result in too high a permittivity. For their correction, therefore, the independently determined electrical conductivity can be used. For manufacturing reasons, the UMP-1 BTim is unable to determine the soil temperature.
The principle for the measurement of the water content corresponds neither to the classic FDR nor the TDR method. The sensor sends a continuous signal of constant frequency (40 MHz1). To determine the dielectric constant, however, it is not the amplitude change that is considered, as in the FDR method, but the phase shift in the received signal. Thus, a time offset to the original signal is measured. The measured time value is assigned a relative dielectric constant of the soil. For this purpose, a tabularly ordered range of values is available, which is calibrated separately for each UMP. The water content is finally determined via the regression function according to Topp and Davis and output in volume%. For independent water content calculations according to other models, however, the εr value can also be called up directly.
l fast and easy measurement
l High precision
l independent conductivity measurement
l Smartphone instead of a handheld device
l Compatible with all Android smartphones
as a compact version (with shaft, integrated probe, height-adjustable handle, smartphone holder and spring guide for grooving) ideal for mobile use -> measurement campaigns with many point measurements over a larger area
more robust due to more stable measuring rods (5 mm Ø)
Measurement data immediately and clearly accessible (smartphone holder integrated on the handle)
Battery only switched on during measurement -> saves capacity
1 The UMP-1 BTim is only manufactured with 150 mm long measuring rods. According to the length, the measuring frequency is 40 MHz.
Measuring frequency for water content: 40 MHz
Antenna length: 150 mm
Antenna diameter: 5 mm
Measuring range water content: 0 ... 100% Vol. Water content
Accuracy water content: ± 2%
Measuring range relative permittivity εr: 0 ... 80
Measuring range electrical conductivity: 0.001 ... 5mS / cm
(Optional value increase to 40mS / cm possible with lower resolution)
Accuracy electrical conductivity: ± 1%
Measuring range soil temperature: -20 ... +60 ° C
Measuring volume: 1000 ml
Operating temperature: -20 ... +60 ° C