Hanna Instruments HI 8001, Инструкция по эксплуатации

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3 FUNCTION DESCRIPTION
In this chapter the main functions of the Fertigation Controller are presented. For
a better understanding see the typical installation schemes utilized for irrigation
and fertilization presented in the Installation Block Diagram, Appendix 5.
3.1 IRRIGATION CONTROL
The Fertigation Controller can control 8 to 32 sectors (one valve per sector) for
each of the ten irrigation programs:
- 1 to 32 valves (sectors) can be selected specifying the sector’s number and
the desired value of irrigation time or volume for a specified irrigation
program-using
Panel S 38 ( SET SECTORS). The panel displays the num-
ber of set sectors for the respective irrigation program
- The current status, set value plus irrigation extension and “Done” time/
volume value for the selected irrigation program/sector are shown on Panel
C 14 (SECTOR STATE).
Irrigation can be controlled by time or volume – irrigation control mode can be
switched between time and volume using panel
S 53 (IRRIG CTRL MODE).
Each irrigation program can be started by:
TIME:
- 1 to 6 different timetables (values) per program can be set using panel S 35
(SET START TIME). “Start cond” must be the selected option on panel S 34
(START CONDITION).
ACCUMULATED SOLAR RADIATION:
- A Solar Radiation set point can be established for starting each program
- The accumulated solar radiation level can be used as a starting condition
for each program
- There are 3 parameters used to start a program by solar radiation:
- The solar radiation sensor threshold value can be established for each
irrigation program. When the solar radiation measured value exceeds the
sensor threshold value the accumulated solar radiation value
is increased.
This parameter can be modified on panel S 43 (Level: xxxxW/m 2 ).
- The accumulated solar radiation value is used to keep track of the mea-
sured solar radiation level during the time interval determined by the previ-
ous start moment of the irrigation program and the actual moment. This
parameter can be seen on panel
S 06 (Irrig = xxxxWh/m 2 ).