8.18 NTC temperature sensor 8.18.1 General characteristics In certain models (i.e. those with hybrid or electronic timers), an NTC sensor is used to control the washing temperature. In these sensors, the internal resistance decreases as the temperature increases. This reduction in resistance is detected by the electronic control system which, when the desired temperature is reached, disconnects the heating element. Two types of sensor are produced; their shapes are different, but their characteristics are identical. NTC sensors are used in electronic washer-dryers to control the temperature and to calculate the drying time. 1. Plastic casing 2. Metal capsule 3. NTC resistor 4. Terminals 1.
NTC resistor 2. Metal capsule 3. Terminals 4. Plastic casing 8.18.2 Electrical symbol 8.18.3 Checking for efficiency Use a tester to check that the resistance of the sensor corresponds to the temperature. SOI/DT 2002-05 eb 89 599 35 23-17 TEMPERATURE (ºC) RESISTANCE (Ω) Rated value Maximum value Minimum value 20 60 80 6050 1250 640 6335 1278 620 5765 1222 660