Motor motor rotor duplex spot welding machine common electrical faults and solutions
First, the power supply failure
1, fault phenomenon
Welding machine can not start, the power indicator does not light up.
Sudden power failure during welding.
2, the possible causes
The plug is not plugged in or the power cord is damaged, resulting in the power supply can not be accessed normally.
The fuse is blown, which may be caused by a short circuit or overload.
The power switch is damaged, with poor internal contact or broken circuit.
Abnormal input voltage, such as too low or too high voltage, beyond the normal operating voltage range of the welder.
3、Solution
Check whether the plug is tightly inserted, if the power cord is damaged, it should be replaced with a new power cord.
Check the fuse, if it is blown, first find the reason of short circuit or overload, and replace the fuse with the same specification after troubleshooting. For example, if the fuse is blown because of a short circuit in the welding electrode, the electrode should be cleaned up and its spacing adjusted first, and then the fuse should be replaced.
Check the conductivity of the power switch with a multimeter, if it is damaged, replace it with a new one.
Measure the input voltage, if abnormal, you can use a voltage regulator to stabilize the voltage to ensure that it is within the voltage range required by the welder (usually within ±10% of the rated voltage).
Second, the welding current failure
1, fault phenomenon
Welding current is too large, resulting in overheating of the welded joints, serious spattering, and even damage to the motor rotor.
Welding current is too small, resulting in insufficient strength of the welded joint, welding is not firm.
Welding current is not stable, the quality of welded joints varies.
2、Possible reasons
The current adjustment knob is damaged or has poor contact, making the set current value inconsistent with the actual output current.
Failure of the welding transformer, such as short-circuited or disconnected windings, will affect the current output and stability.
Damage to power control components such as thyristors (if any), preventing normal current adjustment.
Poor contact between the electrode and the workpiece, resulting in too much or too little resistance, thus affecting the transmission of welding current.
3. Solution
Check the current adjustment knob, clean its internal contacts or replace the damaged knob.
For welding transformer failure, use insulation resistance meter and multimeter to check the insulation resistance and resistance value of the winding to determine whether it is short-circuited or disconnected. If the windings are damaged, a professional is required to repair or replace the transformer.
Check the power control components such as thyristor, if it is damaged, it should be replaced with the same type of components and re-adjust the relevant parameters.
Check the contact between the electrode and the workpiece, clean up the oxides and oil on the surface of the electrode, adjust the electrode pressure to ensure good electrical contact.
Third, the controller failure
1, fault phenomenon
The welder cannot weld according to the set program and parameters, such as welding time, pressure and other parameters out of control.
Controller display (if any) appears garbled, black screen or no display.
Controller frequently crash or restart.
2, the possible causes
Controller program error or loss, may be due to electromagnetic interference, power fluctuations or program memory chip failure.
The controller's internal circuit components are damaged, such as capacitor leakage, chip overheating damage.
The line connecting the controller is loose, short-circuited or disconnected, affecting the signal transmission.
3、Solution
Try to perform a reset operation on the controller to restore its default settings. If the program is missing, contact the welder manufacturer to get the correct program version and reprogram it.
Open the controller shell (under protection) and check the internal components for obvious signs of damage, such as capacitor bulging. Damaged components will require replacement by a service professional.
Check the lines connecting the controller, re-insert loose connectors and repair short-circuited or broken lines.
Fourth, the sensor failure
1, fault phenomenon
Welding pressure sensor failure, resulting in inaccurate electrode pressure, affecting the quality of welded joints.
Temperature sensor (if any) failure, can not properly detect the temperature of the welded joint, may make the welding process out of control.
Displacement sensor (for monitoring electrode displacement, etc.) failure, affecting the welding depth and accuracy.
2. Possible causes
The sensor is subjected to mechanical damage, such as collision, excessive extrusion, etc..
After long-term use of the sensor, its internal components aging or performance degradation.
The sensor's signal wire is poorly connected, loose, short-circuited or disconnected.
3、Solution
Check whether there is any damage to the sensor's appearance, if there is damage, the sensor should be replaced with the same model.
For sensors with reduced performance, use professional calibration equipment to calibrate, if it can not be calibrated to the normal range, it also needs to be replaced.
Check the sensor signal line, reconnect the loose connector, replace the damaged signal line to ensure normal signal transmission.
V. Welding circuit failure
1, fault phenomenon
Welding circuit does not work, can not be welded.
Welding circuit resistance is too large, generating excessive heat, resulting in overheating of the electrode and connection parts.
2、Possible causes
The welding cable is broken, fractured or the connector is loose, so that the welding current cannot pass through normally.
Oxidization or loosening of the connection parts of the electrode and the welding circuit increases the circuit resistance.
3、Solution
Check the welding cable, repair or replace the broken cable, and tighten the loose connectors.
Clean the oxidization of the connection part between the electrode and the circuit, and re-tighten the connection part to reduce the circuit resistance.
The above solutions can effectively solve the electrical fault of unstable welding current encountered by the spot welder in the process of manufacturing motor rotor, thus improving the welding quality and productivity.
