Hardi HC 2500 Series Instruction Book page 19

The flow transducer can be calibrated theoretically or with two practical
methods. For the sake of accuracy, the practical methods are pre-
ferred. Practical calibration is done with clean water. The Flow Tank
method is more time consuming, but is more accurate than the Flow
Nozzle method.
When changing to nozzles with more than a 100% increase or decrease
in output, it is recommended to re-calibration the flow transducer.
Calibration is recommended to be carried out at least once during the
spraying season.
Use the chart at the back of the book to record the values.
Flow constant
F L O W C A L I B R AT I O N
F l o w c o n s t a n t
To change the flow constant theoretically.
During theoretical flow calibration the number of pulses per unit are
shown on the display.
For example, [ 120.0 PPU ] indicates the number of pulses which
theoretically come from the flow transducer whilst 1 litre of liquid
passes through. Approximate PPU values for different flow housings
are as follows:
Housing Code for
housing
BK White
BK & EVC One outside groove
BK Black
EC White
EC Black
EC S/67 One outside groove
S/67 Two outside grooves
F L O W C O N S TA N T
Flow range
l/min
5 - 150
5 - 150
10 - 300
5 - 150
10 - 300
5 - 150
35 - 600
x x x . x P P U
PPU Orifice
value mm
105.0 13.5
120.0 13.5
60.0 20.0
118.0 13.5
59.0 20.0
128.0 13.5
125.0 36.0
19