Comet VR 10 Manual De Instrucciones página 20

The symbol:
marking some parts of the text highlights the possible occurrence of damages to people in case the relevant
prescriptions and indications are not complied with.
The symbol:
marking some parts of the text highlights the possibility of damages to the control unit, in case the relevant
instructions are not complied with.
The products described in this manual are mainly intended to be applied, together with the alternative
positive-displacement (diaphragm or piston) pumps, onto machines for protective treatments of agricultural
crops or onto water and water solution pumping systems (also refer to paragraph
The pump control unit is the unit made up of a pressure unloader/regulation valve and shut-off/distribution
devices of the pumped liquid (e.g. taps).
A pressure unloader/regulation valve is a device allowing to regulate the working pressure and the
pumped fluid to flow back towards the by-pass duct of the pump, so preventing dangerous pressures to
arise, when the delivery is closed or when pressure values are set which are higher than the maximum
permitted values.
In this manual, for sake of simplicity, the pressure unloader/regulation valve will be referred to as
unloader valve and the pump control unit as control unit.
A constant-pressure regulation valve keeps the set-up pressure substantially unchanged when the
rotation speed of the pump to which it is connected varies. As a consequence, the delivery of product
depends on the forward speed of the machine. The higher is the machine speed, less product will be
delivered and vice versa.
A (proportional) positive-displacement regulation valve operates so as to vary the pressure
proportionally to the flow rate and therefore to the rotation speed of the pump it is connected to. This
causes constant product delivery, regardless of the forward speed of the machine, if the same gear ratio is
used. This applies to pump speed variations which are within ± 10% of their initial value.
The anti-dripping eddy is a device allowing to stop immediately the product delivery through an accessory,
thus avoiding useless dripping. It is recommended to use anti-dripping filters or anti-dripping diaphragm
nozzles to ensure a perfect working of the anti-dripping eddy.
CAUTION
• The values of maximum pressure and flow rate shown in the table below refer to high performance models.
Depending on the field of use, models with different performance are also available. Always check and
never exceed the values of maximum pressure and flow rate of the control unit shown on the
identification plate.
VR 10
VR 15
Control unit 4V/6V
Hydra
20
SYMBOLS
CAUTION
WARNING
TECHNICAL FEATURES AND DATA
PERFORMANCE
MAXIMUM FLOW RATE
50 l/min - 13,2 US gpm
50 l/min - 13,2 US gpm
150 l/min - 39,7 US gpm
50 l/min - 13,2 US gpm
MAXIMUM PRESSURE
10 bar - 145 psi
15 bar - 218 psi
20 bar - 290 psi
25 bar - 362 psi
(continued on next page)
).
"INTENDED USE"
MASS
0,3 kg - 0,7 lb
0,5 kg - 1,1 lb
2,0 kg - 4,4 lb
0,9 kg - 2,0 lb