Technical Support - DMM
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13.7 Analogue pressure switch
13.7.1 General characteristics
The electronic pressure switch is an analogue device that controls the water level in the tub, used in models with
electronic control system, and it is directly connected to the main PCB.
1. Small pipe
2. Core
3. Oscillating coil
The pressure switch is connected via a small pipe to the pressure chamber.
When water is introduced into the tub, this creates a pressure inside the hydraulic circuit that causes the membrane
to change position. This in turn modifies the position of the core inside the coil, thus changing the inductance
and the frequency of the oscillating circuit.
The PCB recognises how much water has been introduced into the tub according to the frequency.
1. Main electronic circuit board
3. Analogue pressure switch
Operating frequency variation according to the quantity of water in the tub.
In the event of a fault an alarm will be displayed - see table of alarms.
