Hanna Instruments HI 8001, Инструкция по эксплуатации

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3.3 FERTILIZATION CONTROL
Fertigation Controller can use up to 4 fertilizer tanks.
Each irrigation program can specify the percentage for each type of fertilizer.
These values can be set using panel
S 39 (SET FERTILIZERS).
The fertilization is done in accordance with the conductivity control. Each irriga-
tion program has a specified conductivity target value (conductivity reference
value which is set using panel
S 41 (COND CONTROL);
The percent of applied fertilization can be automatically modified with respect to
an amount of solar energy accumulated since the previous application. The
current fertilizer status (set and current percentage value) can be checked on
panel
C 16 (FERTILIZ STATE).
3.4 pH CONTROL
The pH control is necessary to correct and maintain the pH of irrigation water
within specified values (min and max offset values). Minimum and maximum
offset values are set using panel
S 40 (pH CONTROL). To choose between acid
or alkaline correction you must go to panel C 51 (pH CTRL OPTIONS). In this
panel you can also select pH correction in pre/post irrigation.
The pH correction is made in accordance with a selected pH reference value
specific for each irrigation program. This value can be set using panel
S 40 (pH
CONTROL).
pH control is made with two pH sensors for additional safety and accuracy.
Current status of sensors (main and secondary) in addition to the reference value
is displayed on panel
C 04 (pH STATE).
Main pH sensor value is displayed on panel C 01 (GENERAL INFO) and C 02
(SENSORS STATE)
When the pH is not within the specified range for a period of time (more than
the time specified) or the difference between the 2 pH sensors (main and second-
ary) is greater than the specified difference the pH control will generate a pH
alarm. The specified difference can be set using panel
S 55 (SENSORS CONFIG).
The pH alarm threshold can be set using panel S 40 (PH CONTROL).
Given a pH alarm condition, the pH control can be maintained if “Ctrl on PH
alarm” is selected using panel number
S 52 (ALARM BEHAVIOR).
Given a pH alarm condition, the irrigation can be maintained if “Irrig on PH
alarm” is selected using panel number
S 52 (ALARM BEHAVIOR).
Statistical values of pH are displayed on panel C 22 (TOTAL AVERAGES). For
each irrigation program’s pH average see panel C 23 (PROGRAM AVER-