•C: Position indicator, indicates, according to its colour, the ball position. The colours are
RED and GREEN.
•D: adjusting pressure relief valve knob. Unscrewing manually this part the maximum
pressure is increasing.
•E: compensating discharge adjustment knob. Unscrewing manually this component the
water coming back to the tank decreases, therefore pressure increases.
•M: Pressure gauge
All the control units made by IDROMECCANICA BERTOLINI S.p.A. are always fitted
with the VS adjustable pressure relief valve.
The adjustment of this valve is made by the operator, who must adjust the pressure
to a value that is higher than the maximum working pressure, but lower than the
maximum security pressure attainable by the hydraulic system.
ANYWAY THE MACHINE MUST BE PROVIDED WITH A SEPARATE SAFETY
VALVE, SET AT THE WORKING PRESSURE THAT IS NOT HIGHER THAT
10% OF THE MAX.PRESSURE OF THE HYDRAULIC SYSTEM.
Description of the functions
1. VS Pressure relief valve: It is adjusted manually by its knob (screwing it, pressure
increases, unscrewing it, pressure decreases).
It discharges into the tank the excess liquid when the adjustment pressure is obtained.
2. VG: Main ON-OFF ball valve: it opens or closes the discharge to the tank. The valve
position is showed by the indicator:
•“GREEN” position: discharge to the tank.
•“RED” position: working condition.
It is, for its function, always fitted after the VS valve, in order to use only one
discharge hose.
3. VV: volumetric adjustable pressure valve: It adjusts manually the spraying pressure,
if connected to a sprayer control or automatically if connected to a computer B Matic
500. In this case it provides to increase or to decrease pressure at variable driving
speed of the tractor, keeping the same amount of liquid per surface unit (ex.
Litre/hectare).
The liquid in excess is deviated to discharge.
The valve position is showed by the indicator:
•“GREEN” position: discharge to the tank
•“RED” position: working condition
The rotation of pin is not instantaneous but gradual; it can be 9 seconds (suggested for use
with computer) or 21 seconds (suggested for use with sprayer control).
4. RS section valve: it opens or closes the corresponding boom section; it discharges the
liquid in the tank by the VS valve or VG valve, if present.
The valve position is showed by the indicator:
•GREEN” position : closed boom (discharge in the tank)
•“RED” position: working condition (liquid to the boom)
5. RD section valve: The RD valve is a “deviating valve” that adjusts in by-pass the liquid
amount that you have established with reference to counter clockwise knob adjustment.
This implies a pressure variation if all of the section valves are not adjusted at the same
value (ATTENTION THE ADJUSTMENT IS VERY IMPORTANT).
If you want to increase the pressure to the boom the knob will be turned counter clock-
