January 2001
5C - 14
Functions - Dosing System
Service Manual Cafitesse 500
C.3.4 Function: Switching-over of the Auto-Diaphragm
Fig. 1
1
2
3
5
6
●
The console for screened coil contains a
motor for the auto-diaphragm (1) with a
lever arm (2). (Fig. 1)
●
The combi-trough is equipped with an
autodiaphragm and a lever wire. On the
lever wire a permanent magnet is mounted.
●
A sensor board (3) with 2 Hall-sensors
is mounted in the motor housing. The
Hallsensors react to the permanent magnet
on the lever wire of the auto-diaphragm.
●
In this way the control unit detects 2 diffe-
rent criteria: (Fig. 1)
1.) Position of the auto-diaphragm
(Disconnection of the motor and
determination of the sense of rotation)
2.) Safety test (VDE-regulation), whether the
combi-trough is inserted.
●
Every time the dispenser is switched on an
initialising cycle is carried out. If the auto-
diaphragm does not reach the required
position in time (e.g. due to dirt!), the
further process is interrupted and the
display of the Service Panel shows an error
message (see 'Error Codes', pg. 3-3).
Process after controlling the motor for the auto-
diaphragm
The lever arm (2) leaves its starting position.
A.) The lever arm moves into the slot of the
combi-trough and takes the lever wire (6)
and the permanent magnet (5) with it. The
Hall-sensor (7) is left.
B.) The second Hall-sensor (4) disconnects the
motor for the auto-diaphragm. The lever
arm moves via the lever wire so that it can
take the lever wire with it when it is
triggered the next time.
C.) The auto-diaphragm is switched over.
The lever arm leaves the combi-trough.
A
B
7
4
C
