
Electrical and electronic principles
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light. Applications are possible for self-dipping headlights, a self-dipping interior
mirror, or parking lights that will automatically switch on at dusk.
1.7.18 Thick-lm air temperature sensor
The advantage which makes a nickel thick-lm thermistor ideal for inlet air
temperature sensing is its very short time constant. In other words, its resistance
varies very quickly with a change in air temperature. The response of a thick lm
sensor is almost linear. It has a sensitivity of about 2 ohms/°C and, as with most
metals, it has a positive temperature coefcient (PTC) characteristic.
1.7.19 Methanol sensor ...