Saeco Cappuccino Service Manual - page 66
4. FUNCTION/TIMING
ROYAL
Page 20/22
REV.4 SEPT.2003
Saeco International Group
Gear
Motor
Small
gear
wheel
Large
gear
wheel
Home position
setting microswitch
Home position
setting cam
Home position
setting cam
red blue
black
red
black
brown
Brewing position
setting microswitch
4. Function
4.1. Gearmotor
The gearmotor is a direct current motor and is controlled by the CPU at approx. 30 – 35 V.
In order to perform forwards and backwards movements, the gearmotor is controlled alternately with a
positive and negative half wave.
In the event of overload the motor's electronic system switches off after 8-10 sec. and the machine is
stopped. This situation is indicated by the flashing fault LED. In digital display indicator systems: brewing
unit locked.
Important:
During installation of the large gear wheel care must be taken that the marking on the large gear
wheel always faces the direction of the small gear wheel axis, and that both limit switches are positioned in
the larger segment between both switching cams.
If the motor is replaced, it is important that the blue cable (-) is fitted onto the motor connection near the
writing "Italy" (+ and – are not marked).
4.2. Heating plate (Gear resistor)
The heating plate is operated with a wave packet control system. The ratio of the power-on time is approx.
1:40 (0.1 sec on, 3.9 sec. off). The heating plate is activated via the corresponding item in the user menu. It
is only active when the machine is not operational. The heating plate output is approx. 437 W.
In order to reduce the total power output of the machine, the heating plate is turned off during the heating
stage.
The heating plate can act as a resistor for the gearmotor.
In the event that several coffees are brewed consecutively, the heating plate warms up without being turned
on. The heating plate is protected against overload by 2 thermal fuses.
If one of the thermal fuses is compromised or the heating plate is defective, the gearmotor also does not
function.
Exception:
The Royal Office does not have a heating plate. The gear resistor is the small resistor on the
instantaneous water heater.