
Electrical and electronic principles
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1.7.7 Variable resistance
The two best examples of vehicle applications for variable resistance sensors
are the throttle position sensor and the ap-type air ow sensor. Whereas
variable capacitance sensors are used to measure small changes, variable
resistance sensors generally measure larger changes in position. This is due to
a lack of sensitivity inherent in the construction of the resistive track.
The throttle position sensor, as shown in Figure 1.61, is a potentiometer in
which, when supplied with a stable voltage (often 5 V) the voltage from the
wiper contact will be proportional to the throttle position. ...