evolution G-50 H
Service Manual
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Issue 3.2
a) Determine the direction in which the plate must move; this depends on which micro has
been passed.
b) Locate the slide for the manual activation of the directional valve in the hydraulic
distributor: this is located on the same side of the machine towards which the activation
plate must work.
c) Turn the general switch ON, press the POWER CONTROL key and the MOTOR key.
With the manual valves of the coupling block open, point the gun at a waste container.
d) Press the manual slide of the directional valve and hold it until the activation plate is
centred between the two run end micros.
e) If when pressing the slide, it moves freely, the excess run is due to an electrical
problem. Press the MOTOR key and the NORMAL key; press the run end micros and
check whether the reels are changed and the direction indicator lights: if the reels are
not changed or the direction indicator lights fail to come on, there is an electrical
problem in the run end micro or in the reels of the directional valve.
5.
Over Pressure Safety Switch
Each metering pump is protected by a safety pressure switch factory set to limit the pressure
depending on the size of the pumps installed in the unit. For
1.2
size pumps, the limit pressure
set in the factory is 250 bar (3600 psi). When the limit pressure is reached, the pressure switch
interrupts the electrical supply to the directional valve, stopping the pumps. When the pumps
stop, the direction indicator lights will go out and an alarm will be activated that will be shown on
the control panel (3 if the excess pressure is caused in the Isocyanate circuit or 4 if it is caused
in the Polyol circuit).
When the pressure reaches lower values than the established limit, the metering pumps will
restart. However, the causes of the excess pressure must be determined and corrected.