Netafim NETAFLEX 3G, Installation Manual

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22 NETAFLEX™ 3G INSTALLATION MANUAL
CALIBRATION
The process of calibrating the NetaFlex™ 3G is carried out in three stages:
1. Calculation of dosing channels opening percentage
To finely calibrate the NetaFlex™ 3G in order to achieve homogeneous and stable dosing, perform the
following calculation for each dosing channel (fertilizers and acid) to determine the amount of suction
reduction needed to attain the required fertilizer/acid flow rate.
Flow rate of the largest irrigation shift
Dosing ratio of a single fertilizer/acid
Result: a single fertilizer/acid flow rate
Result: target Rotameter reading
EXAMPLE
=
X
m
3
/hr
l/m
3
l/hr
l/hr
X 1.25 =
30
8
240
300
Metric units
EXAMPLE
X 0.06 =
X
GPM
US gal/1000 US gal
GPH
GPH
X 1.25 =
130
8
62
78
US units
X 0.06 =
X
GPM
US gal/1000 US gal
GPH
GPH
X 1.25 =
=
X
m
3
/hr
l/m
3
l/hr
l/hr
X 1.25 =
Flow rate of the largest irrigation shift
Dosing ratio of a single fertilizer/acid
Result: a single fertilizer/acid flow rate
Result: target Rotameter reading
DEFINITION
Dosing ratio =
The quantity of fertilizer/acid (l)
1 m
3
irrigation water
DEFINITION
Dosing ratio =
The quantity of fertilizer/acid (US gal)
1 THG (1000 US gal) irrigation water
NOTE
The Rotameter's sacle is calibrated by the manufacturer for measurement of the flow rate of water
(H
2
O). Certain inacuracies may be observed when the flow rate of liquids with different densities,
such as fertilizers and acids, is measured.
2. Simulation test with a 10 liter (2 US gal) bucket of water
Instruments needed
• Good-quality portable EC and pH sensors, finely calibrated
• Calibration solutions for EC and pH
• Bucket with a scale for up to 10 liters (2 US gallons)
• Measuring tube or syringe with a scale for up to 100 cc (1 oz)
• Clean (preferably distilled) water for cleaning sensors during calibration
• Blotting paper for cleaning and drying
The client prepares the fertilizer solutions and the acid solution (if required) in the stock tanks according to
the recipe advised by the agronomist/consultant.
ATTENTION
Ensure the fertilizers and acid solutions in the stock tanks have been thoroughly agitated before
starting the simulation.