Disadvantages:
The starting motor of Caterpillar excavator can operate normally before the construction of the proposed machine, although the operation speed is slow. However, after the proposed machine is repaired, the starting motor is significantly weak and cannot start the proposed machine
Defect analysis:
1. Upon inspection, the battery is excellent and the external circuit is free of bad touch
2. Remove the starting motor. It is found that the front and rear copper sleeves are severely worn. After the copper sleeve is replaced, the starting motor is installed and tested. The speed of the starting motor is advanced
3. However, after the drive gear and the gear ring mesh, there is a rhythmic instantaneous disengagement and meshing phenomenon. It is suspected that the gear ring is worn, and the gear ring is removed for inspection. It is found that the wear is not severe
4. Install the gear ring from the top, and then test the machine. The defect is still the same
5 later, when the cover of the starting combination relay was opened, it was found that when the starting motor was powered on, the contact of the protection relay was disconnected in advance. After adjusting the contact arm of the protection relay, everything was normal
Related reading:
The reason for this is that after the starter motor is repaired, the speed advances, and the speed of the alternator also advances. The coil of the starting protection relay is connected to the neutral point of the alternator Although the recommender has not been recommended at this time, the pull-in voltage of the protection relay is much lower than the specified value, and the voltage of the alternator will pull out the contact, which presents the above shortcomings. After the contact arm is adjusted, the shortcomings are eliminated
