How to fault analyze and troubleshoot a series excitation motor motor stator winder?
I. Failure analysis steps
l Observe the fault phenomenon
Observation of operation status: When the winding machine is in trouble, first observe whether the equipment stops working completely or some functions are abnormal. For example, whether the motor is still running, whether the winding shaft can rotate normally, whether the wire arrangement mechanism is still working, and whether their working condition is stable, with or without abnormal vibration, noise or jamming phenomenon.
Appearance check: carefully look at the appearance of the equipment, check whether there are obvious signs of damage. For example, whether there is any burnt or short-circuit marks on the wires, and whether there is any breakage, wear and tear, or loosening of the mechanical parts (such as the winding shaft, the cable arrester, the drive belt, the chain, and the gears, etc.). Also, look for fluid leaks, such as hydraulic oil leaks from the hydraulic system (if there is one), and grease spills from bearings and other parts of the system.
Indicator light and meter check: check the status of the indicator lights on the equipment to determine if any malfunction indicator lights are on. Check the display of parameters such as pressure (if hydraulic or pneumatic equipment), temperature, speed, turns, etc. on the instrument panel to see if there are any abnormal readings, which can provide clues for fault analysis. For example, if the temperature is too high, it may suggest that there is an overload or heat dissipation problem with the motor or certain components; abnormal speeds may be related to the motor, drive train, or control system.
l Collect equipment information
Equipment history query: Understand the use of equipment history, including the use of equipment age, past maintenance records, replaced parts and so on. This information can help determine whether the failure is due to equipment aging, recurring problems or the emergence of new situations. For example, if the equipment has frequent failures of an identical component, then the component and its associated system need to be focused on in this failure analysis.
Operation inquiry: Ask the operator about the operation of the equipment prior to the failure. For example, whether the abnormal operation, such as overload operation (winding speed is too fast, wire diameter is too thick resulting in excessive load on the motor, etc.), incorrect parameter settings (turns set incorrectly, tension settings are unreasonable, etc.), a sudden power failure or power, etc.. At the same time, to understand the equipment at the time of the failure of the work being carried out tasks, such as normal winding or in the debugging process of the failure, which helps to narrow down the scope of the fault.
l Preliminary judgment of the scope of the fault
Classification according to the phenomenon: According to the observed fault phenomenon, the fault is initially categorized into electrical faults, mechanical faults or other system faults. For example, if the motor does not run and there is no sound, it may be an electrical system failure, such as power supply problems, motor failure itself or controller failure; if the winding shaft movement is not smooth but the motor is normal, it may be a mechanical transmission part of the failure, such as belt slippage, screw jamming or bearing damage.
Refer to the schematic diagram of the equipment: With the help of the electrical schematic diagram of the equipment, mechanical assembly diagrams and other technical information, to further narrow down the scope of the fault. The schematic diagram allows you to understand the connection relationship between the various components and the signal flow, so as to determine the possible location of the fault. For example, according to the electrical schematic diagram, you can check the circuit part of the control motor, including relays, contactors, motor controllers and other components; according to the mechanical assembly diagram, you can check the relative position and connection of various components in the transmission chain.
l In-depth inspection of suspicious parts
Inspection of electrical parts: For suspected electrical failure, use tools such as multimeter to check. Parameters such as voltage, resistance, and current can be measured. For example, check whether the resistance of the motor winding is normal, to determine whether there is a short circuit or broken circuit; check whether the output signal of the sensor meets the requirements, such as whether the tension sensor can accurately feedback the tension signal, whether the position sensor can correctly indicate the position of the row of wires; check whether the power supply is stable, including whether the input voltage is in the normal range, and whether the power supply line is broken, grounding and other issues. For electronic components (such as controllers, drives, etc.), you can check whether their operating temperature is too high, whether there is a burning odor, etc..
Inspection of mechanical parts: For parts suspected of mechanical failure, perform an appearance and function check. Check the appearance of mechanical parts for damage (e.g., wear, deformation, rupture, etc.) and for loose connections. For example, check if the drive belt is loose or broken, check if the bearings are stuck or badly worn, and feel if there is excessive resistance or jamming by manually rotating the winding shaft or other rotating parts. For some parts that require precise movement (such as guide rails and silk rods of the spooler), you can check the precision and smoothness of its movement, and observe whether there is any jumping, offsetting and so on.
Second, the common troubleshooting methods
1、Electrical faults
l power failure
Failure phenomenon: the equipment can not start, all the lights do not light.
Elimination methods: first check whether the external power supply is normal, see whether the power plug is plugged in, whether the socket is powered. You can use other electrical equipment to test the socket. Then check whether the fuse inside the device is blown, if it is blown, you need to replace the fuse with the same specification. At the same time, check whether the power line is broken, short-circuited, etc., if necessary to repair or replace.
l Motor Failure
Failure phenomenon: the motor does not run or runs abnormally (such as unstable speed, abnormal sound, etc.).
Elimination method: If the motor does not run, first check whether the power input of the motor is normal, including whether the wiring of the motor is firm and whether the controller has output signal. For brushed motors, check whether the brushes are badly worn or have poor contact, if the brushes are problematic, replace the brushes. If the motor runs but the speed is unstable, check whether the speed sensor works normally and whether its connection is good, and also check the parameter setting and working status of the speed controller, and adjust or replace it if there is any problem. If the motor makes abnormal sound, it may be that the bearing inside the motor is damaged or there is foreign matter entering, it is necessary to disassemble the motor for inspection and cleaning, and replace the damaged bearing.
l Sensor failure
Failure phenomenon: Tension sensor failure leads to uncontrolled winding tension and untidy rows of wires; position sensor failure makes the rows of wires inaccurate position; speed sensor failure leads to unstable winding speed.
Elimination methods: For the tension sensor, check whether its installation position is correct, whether it is blocked by the material. Clean the surface of the sensor and check whether the connection line of the sensor is loose or damaged. Use standard test objects to check whether the output signal of the sensor is normal, if not, it may be necessary to replace the sensor. For position sensors, similarly check the mounting, connections and clean surfaces, and replace or calibrate faulty sensors by manually adjusting the position of the wiring arrays and observing whether the sensor signal changes correctly. For the speed sensor, check whether its connection with the motor shaft is firm, whether the signal transmission is normal, compare the actual speed and the sensor feedback speed, if there is a deviation, adjust or replace.
l Controller failure
Failure phenomenon: the action sequence of the device is chaotic, the parameter settings can not be saved or the device can not respond to the control instructions.
Elimination method: For programmable logic controller (PLC) control system, check whether there are errors in the program (such as logic confusion, program loss, etc.), through the programming software to re-download or correct the program. Check whether the input/output (I/O) module of the PLC is working properly and replace the damaged module. For human-machine interface (HMI) failure, check whether the connection line is loose, whether the screen is damaged, try to restart or update the HMI software. At the same time, check whether the control signal transmission line is interfered with, take shielding measures to reduce electromagnetic interference.
2、Mechanical failure
l winding shaft failure
Failure phenomenon: the winding shaft does not rotate, rotate smoothly or jump too much.
Elimination method: Check whether the transmission components (such as belts, couplings, etc.) between the winding shaft and the motor are normal. If it is a belt drive, check whether the belt is loose or broken, if necessary, adjust the belt tension or replace the belt; if it is a coupling connection, check whether the coupling is damaged or loosely connected, repair or replace. Check whether the bearing of the winding shaft is damaged or not, by manually rotating the winding shaft, feel the resistance of the bearing and whether the rotation is smooth, if there is any stagnation phenomenon, replace the bearing. At the same time, check whether the bobbin is bent or deformed, try to straighten the bobbin for slight deformation, and replace the bobbin for serious deformation.
l Failure of wire arranging mechanism
Failure phenomenon: row line is not uniform, row line is not smooth or row line position is not accurate.
Elimination method: Check whether the transmission parts (such as screws, gears, etc.) of the wire arranging device are normal. For the screw drive, check whether the screw is bent, wear and tear, whether the fit between the screw and the nut is smooth, if there is any problem, you can replace the screw or adjust the fit gap; for the gear drive, check whether the gear is worn out, whether the teeth are damaged, if you need to replace the gear. Check whether the guide rail of the wiring harness is parallel and straightness meets the requirements, clean the surface of the guide rail, add the right amount of lubricant to ensure that the wiring harness can slide smoothly on the guide rail. At the same time, check whether the positioning device (such as position sensor, etc.) of the wire arrangement mechanism is accurate, if there is any deviation, calibrate or replace it.
l Failure of tension adjustment mechanism
Fault phenomenon: unstable winding tension, too loose or too tight.
Elimination method: Check whether the tension wheel of the tension adjusting mechanism is normal. Whether the surface of tension wheel is worn, if it is worn, it will lead to unstable tension and need to replace the tension wheel. Check if the tension adjusting spring is fatigued or damaged. Restore the normal tension adjusting function by adjusting the tension of the spring or replacing it with a new one. Check the tension sensor (if any) and its associated control system to ensure that the tension signal can be accurately fed back and used to regulate tension.
l Mechanical vibration and noise failure
Failure phenomenon: abnormal vibration during the operation of the equipment, affecting the accuracy of the winding; a large noise, interference with the working environment and may indicate that there are potential problems with the equipment.
Elimination method: Check whether the foundation of the equipment is solid. If the equipment is installed on an unstable foundation, it will generate vibration, and it is necessary to re-install the equipment to ensure that it is installed on a solid, level foundation, and use ground bolts, etc. for fixing. For vibration and noise generated by mechanical parts, check whether the transmission parts are installed correctly, such as whether the belt and chain are properly tensioned and whether the gear mesh is good. Adjust the tension or replace the worn transmission parts. At the same time, check whether there is interference between the various moving parts, eliminate the interference point. For rotating parts (e.g., motor, bobbin, spooler, etc.), check their balance, and for unbalanced parts, add balancing blocks or carry out dynamic balancing correction to reduce vibration.
※ If you still can't solve the problem by the above ways and means, please contact the technical specialists of Xinhui Electromechanical Equipment Co.
