Decagon Devices MAS-1 Kullanıcı Kılavuzu - Sayfa 8
Aksesuarlar Decagon Devices MAS-1 için çevrimiçi göz atın veya pdf Kullanıcı Kılavuzu indirin. Decagon Devices MAS-1 20 sayfaları. 4-20 ma soil moisture sensor
Ayrıca Decagon Devices MAS-1 için: Operatör El Kitabı (18 sayfalar)
MAS-1 Soil Moisture Sensor
3. Integrating the MAS-1
3. Integrating the MAS-1
A 4-20mA system generally consists of a sensor, a transmit-
ter, a power supply, and a device to read the current being
transmitted through the current loop. The MAS-1 is an inte-
grated sensor and 4-20mA transmitter. When the MAS-1 is
powered by the Power Supply, it transmits a current though
the loop that is proportional to the soil dielectric permittivity
and therefore the soil volumetric water content.
In Figure
1, the current loop is shown by the dotted line labeled I=4-
20mA. The arrows indicate the direction of the current.
Figure 1 - 4-20mA current loop diagram
The MAS-1 uses a microcontroller to regulate the interval at
which it takes measurements. It takes one second from the
time it is powered up to take its first measurement and trans-
mit current though the loop. The trasnmitted current will
reach a stable value within four seconds of power up. After
the initial four second startup, measurements are taken every
one second, while the current in the loop is continuously
maintained. Since the measurement intervals are controlled
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