It is inevitable that electrical equipment will malfunction during operation. Mastering certain maintenance principles can not only greatly improve maintenance efficiency, but also cultivate good maintenance habits to ensure personal and equipment safety.
1. Repair after power off first
During the overhaul, you must first power off your own, hang up the warning sign and notify your colleagues before you can start overhauling. To know that most accidents are caused by communication problems, many years of experience tell us that power-off must be completed by itself.
2. First move your eyes and do it again
For faulty electrical equipment, do not respond to the hands-on, you should first ask before and after the failure and the phenomenon of failure. For unfamiliar equipment, you should also be familiar with the circuit principle and structural characteristics, and abide by the corresponding rules. Before disassembling, be fully familiar with the function, position, connection method and relationship with other devices around the electrical components. Be sure to look at the drawings first. If there is no assembly drawing, you should disassemble and draw sketches and mark them.
3. External exterior
Check the electrical equipment components for obvious cracks and defects, understand the maintenance history, service life, etc., and then check the interior. Before the disassembly, the surrounding fault factors should be excluded, and it can be disassembled after the electrical components are faulty. Otherwise, blind disassembly may worsen the equipment.
4. Mechanical and electrical
Only after determining that the mechanical parts are not faulty, perform an electrical inspection. When checking the circuit fault, you should use the testing instrument to find the fault location, and confirm the faultless fault after the contact, and then check the operational relationship between the line and the machine in order to avoid misjudgment.
5. Dynamic after static
When the device is not powered, determine the quality of the electrical device buttons, contactors, thermal relays, and fuses to determine where the fault is. Power-on test, listen to its sound, measure parameters, determine faults, and finally perform maintenance. For example, when the motor is out of phase, if the three-phase voltage value cannot be determined, it should be heard and the relative ground voltage measured separately to determine which phase is defective.
6. First clean and repair
For heavily polluting electrical equipment, first clean the buttons, wiring points, and contact points to check if the external control keys are malfunctioning. Many faults are caused by dirty and conductive dust, which is often ruled out after cleaning.
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