Rain Master Weather Center II, User Manual

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Weather Center II User Manual Rain Master Irrigation Systems
Page 26
3.2 Weather Center Theory of Operation
The principle of the Rain Master Weather Center II is to directly measure
the effects of weather and estimate the evapotranspiration loss of water
from the reference crop (i.e. Turfgrass). Transpiration is the movement
of water from plant tissues directly into the atmosphere.
Evapotranspiration is the sum of transpiration and water evaporated from
the soil where water may have accumulated from irrigation, and/or
rainfall.
The Rain Master Weather Center calculates the effects of solar radiation,
wind, humidity and temperature on cool season turfgrass every 10
seconds and as required, outputs one or more Evapotranspiration pulses,
where it is recorded at the rate of one pulse for every 0.01 inches of
water loss. The accumulated pulses are output, by the Weather computer
every 10 minutes, as required.
3.3 ET Electrical Interface
3.3.1 Evolution DX2 Weather Interface
The ET pulse is provided to the Evolution DX2 controller through a
sensor circuit board (DX-FLOW). The pulse is shaped at the sensor
board and forwarded to the controller board for accumulation.
3.3.2 RME Eagle Weather Interface
The ET pulse is provided directly to the RME Eagle Controller at
the sensor input connector as depicted in
Figure 18 - RME Eagle Sensor Interface Connections.