Baseline Systems BaseStation 3200 V12 - Manual (Page 120)

BaseStation 3200 Advanced Irrigation Controller Manual
ET-based watering A watering methodology that uses the principles of evapotranspiration to
water when needed rather than on an established schedule
evaporation Loss of water as vapor from the soil surface or from moisture on the
surface of a leaf. Differs from transpiration in that the water does not
pass through the plant parts.
evapotranspiration
(ET)
The process of transferring moisture from the earth to the atmosphere by
evaporation of water and transpiration from plants.
field capacity This is the maximum water holding capacity of the soil, in other words,
the level of soil moisture left in the soil after drainage of the gravitational
water. Irrigation to levels above field capacity will result in runoff or
drainage as gravitational water.
flow device A device that is capable of measuring water flow and water used
GPH The abbreviation for gallons per hour
GPM The abbreviation for gallons per minute
hydrozone A grouping of plants that have similar water requirements and can be
watered the same
infiltration The process by which water passes through soil – the liquid permeates
the soil by passing through the pores in the soil
k-value (also known as k-factor) A calibration factor for a flow device expressed in
pulses per unit volume. The k-value is used to calibrate the volumetric
throughput of a flow device. Manufacturers give the k-value (or k-factor)
of their flow device in the device specification.
linked zone Within a zone group, there is one primary zone and all other zones are
then “linked” to the primary and will get their programming information
from the primary (water time, program, schedule, etc.)
lower limit
(lower threshold)
This water strategy is programmed by setting the schedule to water every
day and then setting the biSensor to allow watering when the moisture
level drops below this limit – the controller can automatically set this
lower limit after a calibration cycle, or it can be set manually.
mainline A pressurized pipe that supplies water from the point of connection
(water source) to the valves
master valve (MV) An automatic or manual valve installed on the mainline piping
maximum allowed
depletion (MAD)
When the soil moisture content reaches this level, irrigation needs to
start. In most cases, the maximum allowed depletion level is just before
the plants begin to show visible signs of stress.
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