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2.9.4 Electronic control unit
The electronic control unit is the ma-
chine’s “brain”, since it monitors and con-
trols the appliance’s full operation.
The information concerning the in-
stalled software (date and version) can be
seen on the display when the machine is
turned on. The monitoring and control of
the appliance’s full operation.
The information concerning the in-
stalled software (date and version) can
be seen on the display when the machine is turned on.
2.9.5 Volumetric dosing
The volumetric dosing device measures the quantity
of water sent to the group in order to dispense coffee.
The dosing device generates an electrical impulse
which is sent to the electronic
control unit.
The dosing device gener-
ates electrical pulses that are
sent to the control unit and
get counted when the dose is
being programmed.
2.9.6 Motor pump
THIS is a component that
feeds the machine, by raising
the water pressure to 8 - 9
bar in order to dispense cof-
fee and automatically fill the
heating unit.
2.9.7 Automatic Water Entry
The Automatic Water Entry system (AWE) is designed
to check the water level of the heating unit. It consists of:
•
A level probe (short) (
1
) and safety probe (long) (
2
)
inserted in the heating unit, composed of a stainless
steel rod;
•
An electronic control unit;
•
A hydraulic circuit with a motor pump and solenoid
valve which are controlled by the electronic control
unit.
If the water level drops while the machine is operat-
ing normally, the level probe (
1
) sends a signal to the
electronic control unit, which activates the motor pump
and the filling solenoid valve, which in turn restores the
water level in the heating unit.
If the level is very low or there is no water in the
heating unit (during the machine's installation or due
to a failure), the safety probe (
2
) sends a signal to the
control unit which deactivates 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 heating unit.
To prevent any flooding caused by machine mal-
functions or leaks in the hydraulic circuit, the electronic
control unit has a “Timeout” device which stops the
automatic water filling operation after a maximum op-
erating time.
When installing machines with three or four groups,
the initial water filling time may exceed the established
timeout limit. Should this occur, simply turn the machine
off and then back on to restore normal operating condi-
tions.
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Summary of Contents for 2GR
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