What are the common sensor failures and their solutions for motor motor rotor duplex spot welder?
Motor motor rotor duplex spot welding machine common sensor failure and its solution:
First, the pressure sensor failure
l Failure phenomenon
Pressure detection value deviation: the displayed pressure value does not match the actual electrode pressure, may be too high or too low pressure reading. For example, when the actual pressure of the electrode is the normal welding pressure, the pressure sensor shows that the pressure is too high, causing the operator to adjust the pressure parameters incorrectly and affecting the welding quality.
Unstable pressure signal: The pressure signal output from the pressure sensor fluctuates frequently, making the electrode pressure unstable during the welding process, and the quality of the welded joints varies, resulting in false welding or over-welding.
No signal output from the pressure sensor: the equipment cannot obtain the pressure data, and the control system cannot make corresponding adjustments according to the pressure, resulting in the welding process may not be normal due to uncontrolled pressure.
l Possible reasons
The sensor is subjected to mechanical shock or long-term vibration, the internal components are damaged or displaced, affecting the accuracy of pressure measurement.
Poor connection of the sensor's signal line, such as loose plug, broken line or poor contact, resulting in signal transmission interruption or interference.
Zero drift or poor linearity after long-term use of the sensor, which may be caused by aging or performance degradation of the internal strain gauges, capacitors and other sensitive components.
Improper installation position of the pressure sensor, such as not vertically mounted or installed in areas subject to strong interference, affecting the accuracy of pressure detection.
l Solution
Check whether the sensor has obvious physical damage, such as shell rupture, deformation and so on. For damaged sensors, replace the pressure sensor with the same model and make sure the installation process is correct to avoid mechanical damage again.
Check the connection of the signal line, re-plug and unplug the plug to ensure a solid connection. Use an insulation resistance meter to check whether the line is broken, if so, repair or replace the signal line. At the same time, check whether the signal line is laid in parallel with other strong electric lines to avoid electromagnetic interference, and use shielded lines if necessary.
Calibrate the sensor, use the standard pressure source to calibrate the zero point and range of the sensor according to the requirements of the equipment manual. If normal accuracy is still not achieved after calibration, consider replacing the sensor, as the aging of the internal components may not restore performance through simple calibration.
Re-adjust the installation position of the sensor to ensure that it is mounted vertically in a position that accurately detects the electrode pressure and is away from strong magnetic fields, strong electric fields or other sources of interference.
II. Temperature Sensor Failure
l Failure phenomenon
Temperature detection error: the displayed temperature of the welded joint is significantly different from the actual temperature, which may lead to inaccurate control of welding time and energy, affecting the quality of the welded joint. For example, the actual temperature of the welded joint has been too high, but the temperature sensor shows that the temperature is too low, so that the welding time is too long, resulting in overheating of the welded joint, spattering.
Temperature signal abnormality: the temperature sensor output signal jumps, interruptions or persistent unchanged, so that the control system can not correctly determine the temperature change of the welded joints, can not adjust the welding parameters in a timely manner.
Temperature sensor failure alarm: the equipment control system displays the temperature sensor failure alarm message, but the actual welding process seems to be normal, which may be a false alarm of the sensor itself or a precursor of an impending serious failure of the sensor.
l Possible causes
The probe of the temperature sensor is contaminated, such as stained with welding spatter, oil, etc., affecting the heat transfer and temperature detection accuracy.
Problems with the sensor's connecting wiring, such as short circuits, broken circuits or poor contact, resulting in the temperature signal can not be transmitted properly.
The temperature sensor's own performance degradation, may be due to long-term work in a high temperature environment, the internal thermal element aging or damage.
The calibration parameters of the sensor are lost or incorrect, making the detected temperature inconsistent with the actual temperature.
l Solution
Clean the probe of the temperature sensor, use appropriate cleaners and tools to carefully remove contaminants from the probe surface. After cleaning, check if the temperature detection is back to normal.
Check the connection wiring to see if the wiring is broken, shorted or has poor contact. For wiring problems, repair or replace damaged sections to ensure good wiring connections.
For temperature sensors with degraded performance, try recalibration. If the temperature still cannot be detected accurately after calibration, or if the internal components of the sensor are obviously damaged, such as an open or shorted thermistor, the temperature sensor should be replaced.
Check the calibration parameters of the sensor and look in the device control system to see if any calibration parameters are incorrect. If the parameters are missing, re-calibrate according to the requirements of the equipment manual.
Third, the displacement sensor failure
l Fault phenomenon
Inaccurate displacement detection: the displayed electrode displacement does not match the actual displacement, resulting in improper control of the welding depth, affecting the quality of the welded joint. For example, when precise control of the depth of electrode downward pressure is required for welding, the incorrect reading of the displacement sensor may make the electrode downward pressure too deep or too shallow, resulting in welded joint quality problems.
Loss of displacement signal or abnormal: the displacement sensor can not output the normal displacement signal, or the signal jumps, sudden changes and other abnormalities, so that the equipment can not accurately determine the position of the electrode, the welding process may be out of control because of the position of the control of the failure.
Slow response of the displacement sensor: the response of the sensor to the electrode displacement is too slow, resulting in the control system can not adjust the welding parameters in a timely manner, such as in the high-speed welding process, can not be adjusted in time according to the electrode position changes in the welding current and time.
l Possible reasons
Problems in the mechanical transmission part of the displacement sensor, such as loose, worn or jammed connecting rods, gears and other parts, affecting the accurate transmission of displacement signals.
The signal line of the sensor is interfered or damaged, such as electromagnetic interference, signal line is pinched off, etc., resulting in abnormal signal transmission.
The detection elements inside the displacement sensor such as optical, electromagnetic or capacitive are damaged, affecting the accuracy and response speed of displacement detection.
The installation position of the sensor is changed, or the relative position between the sensor and the object to be detected is incorrect, resulting in deviation in displacement detection.
l Solution
Check the mechanical transmission part of the displacement sensor, tighten the loose parts, replace the worn or jammed parts, and ensure that the mechanical transmission part can smoothly transmit the displacement signal.
Check the condition of the signal line to see if there is a source of electromagnetic interference, such as large motors and transformers nearby. For disturbed signal lines, use shielding measures, such as using shielded wires or adding shielding covers. If the signal line is damaged, repair or replace the signal line.
For displacement sensors with damaged internal components, repair or replace depending on the damage. If the optical components are damaged, the optical system may need to be calibrated and replaced by a professional; if the electromagnetic or capacitive components are damaged, after replacing the corresponding components, a performance test is also required.
Re-check and adjust the installation position of the sensor to ensure that it is correctly positioned relative to the object to be detected and securely mounted. After installation, carry out calibration of displacement detection to ensure detection accuracy.
※ If the above ways and means still can not solve the equipment failure, please contact Xinhui Electromechanical Equipment Co., Ltd. technical specialists through the page chat tool to seek help.
