Autronica SM4, Руководство пользователя

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SM4 Manual by MRM-Racing V3.0
15
Throttle Position Sensor
The throttle position sensor (TPS) should be mounted directly on the main throttle, shaft or
alternately connected to this shaft a rigid lash free linkage. Either a linear or rotary type
potentiometer sensor may be used. Its electrical resistance should be in the range 2000 to
20,000 OHMS. Movement of the throttle over its full travel must not stroke the sensor to its
limits of mechanical travel; otherwise damage to the sensor may result. Mounting and/or
linkage construction must be such that the travel is always less that the total available
electrical travel.
Before connecting to the sensor, you need to find the TPS supply, TPS ground and TPS
signal on the sensor.
Some TPS have more than three wires, these sensor are normally suitable, you will only
need to use three of the wires.
To find TPS supply, TPS ground and TPS signal terminals on the sensor use a multimeter
to test the Ohms resistance across the terminals.
The TPS supply, TPS ground terminals will give a ohms resistance that will not change as
the throttle is opened and closed.
When you have found these, test from each one of these to another terminal until you find
the two terminals that the resistance decreases as the throttle is opened.
Example:- Throttle closed resistance 4.2 K ohms.
Throttle open resistance 1.2 K ohms.
When you have found these you are testing across the TPS supply and TPS signal. The
other terminal is the TPS ground.
The electrical connections to the two ends of the potentiometer (fixed terminals) must be
chosen so that the output voltage increases with increasing throttle opening. If the reverse
occurs then the two end terminal connections should be interchanged. A voltmeter should
be used to check the output voltages at the extremes of travel. Ideally the sensor should be
mounted so that the throttle closed output voltage should be between 0.5 and 0.6 volts.
The following conditions MUST be met:- .
1. Throttle is fully closed the output voltage MUST be in the range 0.4 volts to 1.8 Volts.
2. Throttle fully open the output voltage MUST be in the range 3.2 to 4.7 volts.
3. The difference between the voltages at the extremes of travel should be greater than
2.5 volts.
4. The voltage should increase smoothly with increasing throttle opening; there should
be no dead spots in the total throttle travel.