12 unigreen
4.8 PRESSURE REGULATOR
To use the pressure regulator, follow the instructions in the enclosed
handbook scrupulously. The pressure regulator controls all of the most
important spraying functions, the thorough knowledge of its functions makes
work easier and more precise.
The working pressure and the maximum pressure of the sprayer are
determined by the pressure regulator which also protects the circuit from
overpressure in any work conditions. (In serious but very rare cases, if the
connecting pipes get blocked the pressure relief valve lets the pressure off)
In some setups there may be a pump that can reach a pressure of 50 bar
controlled by a regulator designed for 20 bar. In this case the maximum
pressure that can be reached is 20 bar.
The regulators can be manual, mounted on the sprayer or at a distance to
make the controls easier to use; or electrical with a control panel in the cabin.
There are also regulator versions with mechanical remote controls with a
cable. If the tractor has a waterproof cabin the use of electrical controls is
obligatory.
4.8.1 COMPONENTS OF THE PRESSURE REGULATOR
Below you will find the indications for the main models fitted on Unigreen
products.
A main ON-OFF command: “open” lets the fluid flow into the circuit in use;
“closed” empties the tank.
B maximum pressure valve: adjusted by hand with the relevant knob (drains
the excess liquid when the set pressure is reached).
C jets section tap: opens the corresponding jet boom or drains to the
compensation regulator (G).
D auxiliary tap: can be used for various accessories (it is always manual).
E volumetric pressure valve (proportional):
(when present) it regulates the spraying pressure. The valve automatically
compensates variations in speed (within the scope of the same gear ratio),
keeping the quantity of liquid supplied per surface unit (litres/hectare)
unchanged.
F self-cleaning filter: filters the delivery liquid.
G compensation regulators: suitably regulated, these make it possible to
keep the pressure constant when one or more sections of jets is closed, they
don’t influence treatments with the boom fully open.
H manometer: indicates the working pressure.
Connections:
R1 supply union
R2 drain union
R3 volumetric drain union
R4 jets section delivery union
R5 auxiliary delivery union
Control box for GCP ELETTRICO electrical regulators
I1 main control valve switch
I2 volumetric pressure valve switch (proportional)
I3 jets section valves switches
4.8.2 GENERAL INSTRUCTIONS
When using the pressure regulator, scrupulously observe the instructions in
the enclosed handbook, below you will find generic indications for the major
models fitted by Unigreen.
All the regulation and adjustment tests must be carried out with clean
water.
Pressure regulators without a volumetric valve (GCP3-way - GRH-RVA)
Adjusting the maximum pressure valve
= put main control A in the drain position (“OFF”).
= loosen the hand wheel of maximum pressure valve B completely
(anticlockwise).
= start the pump by activating the power-takeoff of the tractor at 540rpm
= open main control A (position “ON”), the manometer will be activated
= open all of the section valves C (position “ON”)
Don’t use the sprayer
without having consulted
the enclosed handbook.