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TECHNICIANS manual
2.6.4 Electronic control unit
The electronic control unit is the nerve
center of the machine. It monitors and
controls all operation of the unit.
By entering the section "Menu" (see
instructions in the next chapters) and se-
lecting the key
, you can view the
information about the installed software
(date and version).
2.6.5 Volumetric dosing
The volumetric dispenser serves the purpose of
measuring the quantity of water sent to the group for
coffee dispensing.
The dispenser generates an electrical pulse which is
sent to the electronic control unit.
The dispenser generates
electrical pulses that are
sent to the control unit and
counted during program-
ming of the dose.
The flashing of the LED (
X
)
indicates that the electrical
impulse has been sent from
the dispenser to the control
unit.
2.6.6 Motor pump
This is a component that
feeds the machine, raising
the water pressure to 8 - 9
bar for coffee dispensing
and automatic filling of the
boiler.
X
2.6.7 Automatic Water Entry
The Automatic Water Entry system is for checking the
boiler level. It is composed of:
•
level probe (short) (
1
) and safety probe (long) (
2
)in-
serted in the boiler, composed of a stainless steel rod;
•
electronic control unit;
•
hydraulic circuit controlled by a motor pump and so-
lenoid valve controlled by the electronic control unit.
When, during the normal operation of the machine,
the water level drops down, the level probe (
1
) sends a
signal to the electronic control unit, which activates the
motor pump and the filling solenoid valve, thus restoring
the level of water in the boiler.
If the level is very low or there is no water in the
boiler (during the machine's installation phase or due
to a failure), the safety probe (
2
) sends a signal to the
control unit which de-activates operation of the heating
element to keep it from overheating and activates the
motor pump and the solenoid valve to restore the level
of water in the boiler.
To avoid possible flooding due to machine malfunc-
tions or leaks in the hydraulic circuit, the electronic
control unit includes a “Time-out” feature that cuts off
automatic filling after a maximum operating time.
During the installation of machines with three or four
groups the initial water filling time may exceed the estab-
lished time limit. In this event, just switch the machine off
and then back on to restore normal operating conditions.
1
2
