A common fault in tractor electrical systems is that the DC generator fails to generate electricity. The following aspects should be analyzed to locate the fault:
1. No conductivity: This is mainly due to wear, burnout, jamming, broken coil springs, severe rectifier surface corrosion, damaged carbon brush insulation pads, and loose wires.
2. Burned-out armature coil: Prolonged overload and reverse current from the battery can easily cause the armature coil to burn out. Check the current limiter and breaker for proper functioning and troubleshoot accordingly.
3. Damaged rectifier insulation mica: Damage can cause a short circuit, preventing the generator from generating electricity. In this case, disconnect the armature winding and solder the wires. Connect one end of a light bulb to the power supply, the other end of the power supply to the armature shaft, and the other end of the bulb to the rectifier. If the bulb lights up, it indicates a short circuit. 4. Excitation coil short circuit and open circuit: In case of a short circuit, separate the grounding carbon brush from the rectifier using insulating paper. Then connect one end of the excitation coil to a light bulb, the other end of the bulb to the power supply, and the other end of the power supply to the generator housing. If the bulb lights up, it indicates that the insulation of the excitation coil is damp or damaged, causing the short circuit.
In case of an open circuit in the excitation coil, separate the two brushes with insulating paper, disconnect the insulated carbon brush connector and connect it to one end of the power supply, the other end of the power supply to a light bulb, and the other end of the bulb to the excitation coil terminal. If the bulb does not light up, it indicates a short circuit.
5. Generator bearing wear: This can easily cause severe friction between the armature and the excitation coil, leading to a short circuit and failure to generate electricity.
