Speed Sensor In The Traction Motor - Linde E25 Service Training

Service Training
2. By depressing the brake pedal.
Depressing the brake pedal applies the battery positive signal from the key switch via braking current switch
1S5 to 1X13:1 at the electronic traction control unit. The battery positive signal flows on via 1X13:15 to the
positive directional contactor terminals.
When regenerative braking is activated, the battery negative signal is applied via 1X13:18 to regenerative
braking contactor 1K5 and via 1X13:4 to circuit breaking contactor 1K6. Both contactors remain activated
until the truck speed has reduced to approx. 0.45 km/h.
Truck speed and the direction of travel are sensed by a speed and direction of rotation sensor mounted on
the left-hand traction motor 1M2.
NOTE: Regenerative braking can only be started when truck speed is over 0.9 km/h.
2.6.6.9.1

SPEED SENSOR IN THE TRACTION MOTOR

The speed sensor is powered with a d.c. voltage of 5 Volt via an amplifier circuit. The sensor supplies two
output signals, which have a different frequency or phase relationship, depending upon the motor speed and
direction of rotation.
FUNCTIONAL CHECK:
Power supply:
- Jack up the truck and support it safely.
- Check the power supply for amplifier 1A5.
- Connect a voltmeter to 1X1.2:1 and 1X1.2:3.
The supply voltage must be 15 Volt.
- Check the power supply for the speed sensor.
- Connect a voltmeter to 1X1.1:1 and 1X1.1:3.
The supply voltage must be 5 Volt.
Output signal:
- Check the speed sensor output signal.
- Connect a voltmeter to 1X1.2:2 and 1X1.2:3.
- Let the traction motors run.
The output voltage must be approx. 7.5 Volt.
- Connect a voltmeter to 1X1.2:4 and 1X1.2:3.
- Let the traction motors run.
The output voltage must be approx. 7.5 Volt.
Section 2.6
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