Hanna Instruments HI 8001, Инструкция по эксплуатации

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4
1 THEORY OF FUNCTION
Irrigation is one of the most important operation in agriculture. With proper
irrigation the quality and quantity of crops can be significantly enhanced.
Correct irrigation is not a simple process: the quantity of water must be suffi-
cient for crops, and if not, photosynthesis and overall growth is impeded.
However, if the amount of water is more than required, plant growth may
become excessive producing a taller, softer and/or damaged product.
The Fertigation Controller can control the quantity of irrigation water based
on time or volume. Different sectors can be irrigated at different times during
a day with different water quantities.
In the Fertigation Controller each irrigation program provides control of pH
and conductivity. When necessary, a specific program performs a pH correc-
tion by the introduction of an acid or base into the irrigation water. pH control
is based on multiple sensor input and a specified set point, while conductivity
control is directly related to the level of fertilization.
When the Fertigation Controller commands the addition of 1 to multiple fer-
tilizers to the irrigation stream, conductivity sensors continually monitor the
conductivity of the stream and the overall amount of fertilization is maintained
based on a specified set point (limit). The Fertigation Controller can com-
mand the addition of multiple (1 to 4) fertilizers to irrigation water. The per-
centage of each fertilizer is set by the user and controlled by a specific pro-
gram based on the conductivity set point.
If a pH or conductivity control problem arises, the program generates an
alarm to inform the user. All operations of both control processes are stored in
memory.
The Fertigation Controller performs all necessary operations in the monitoring
and control of irrigation and fertilization processes. These operations are con-
ducted continuously throughout the day, month and year. To use and man-
age the system properly, all the necessary control values must be set (Setup
mode). During monitoring operations (Consulting mode) the user can ob-
tain information about how the system and irrigation process are functioning,
in addition to the history of all operations for current and previous days. To
view the required information on the display or set a specific parameter, the
appropriate display panel has to be selected, as explained in this manual.