TSE-P 02.00 EB
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599 35 24-30
5.3 Instantaneous door safety device
Certain models are fitted with an instantaneous door
safety device; this means that the door can be opened
as soon as the drum stops rotating.
1. PTC solenoid protector
2. Solenoid
3. Lever mechanism
4. Cam
5. PTC - bimetal
6. Electrical contacts (main switch)
7. Latch
1. Main
switch
2. Solenoid
3.
PTC solenoid protection
4. Bimetal
PTC
5. Connector
Operation principle
When the ON/OFF button is pressed to switch the appliance on, the bimetal PTC is powered; the cam is in
a position which prevents the latch from moving outwards.
When the START/PAUSE button is pressed to start the programme, the main PCB transmits a signal
(duration 20 msec) to the solenoid (at least 6 seconds after the appliance is switched on). The solenoid
causes the cams to rotate one position. This raises the latch which holds the cursor of the door safety
device in position and, at the same time, closes the contacts of the main switch, which thus powers all the
components in the appliance.
At the end of the programme, the board transmits two signals (at an interval of 200 msec and having the
same 20 msec duration):
- the first signal moves the cams a further position, though without releasing the latch.
- the second signal (which is transmitted only if the system functions correctly) moves the cams another
position, which causes the latch to retract, thus releasing the safety device. At the same time, the
contacts of the main switch are opened.
Conditions of door opening
Before transmitting the door aperture signal, the main PCB checks that the following conditions are
observed:
•
the drum must be stationary (i.e. no signal received from the tachometric generator)
•
the water must not be above the lower lip of the door
•
the temperature of the water must be not more than 40°C.
Automatic release device
In case of a power failure, or if the appliance is switched off using the ON/OFF button, or if the solenoid
should malfunction, the bimetal PTC cools over a period varying from 55 seconds to 4 minutes (at a
temperature of 65°C), after which the door lock is released.
Solenoid protection
A PTC is connected in series with the solenoid with the purpose of limiting the current (and thus possible
overheating) in the following cases:
•
TRIAC on the main PCB short-circuited
•
Repeated actioning of the START/PAUSE button (more than 10 times)
