The basic requirements of machine tool electrical equipment maintenance and the diagnosis steps of electrical equipment faults

Release time:

2021-05-18

To troubleshoot problems in time when machine tool electrical equipment malfunctions, first of all, maintenance personnel are required to fully grasp the theoretical knowledge of electrical equipment. For maintenance electricians, to find the operation problems of machine tools, they need to have a more adequate and comprehensive theoretical basis than ordinary workers. Maintenance work is a kind of mental work to a certain extent, most of the time is thinking and troubleshooting, but the maintenance work after finding the fault is relatively easy.

Diagnostic steps of machine tool electrical equipment failure:

(1) Diagnostic steps of electrical equipment failure

When the electrical equipment of the machine tool fails, the maintenance personnel should not start the fault inspection in an emergency, but should do the investigation work first. First of all, investigate the operating conditions of the machine tool before the machine failure occurs and the specific phenomenon of the failure with the machine tool operator, such as the time of the failure (before and after the start-up or during operation), the running action when the machine fails, and what operation may have caused the machine failure. And whether there are precedents for similar failures, etc.; after the investigation is sufficient, some basic components of the electrical equipment should be checked first, such as whether the fuse is blown, whether the wire is intact, whether the motor is running normally, etc.; then the maintenance personnel start circuit analysis , The circuit analysis should be carried out based on the circuit schematic diagram of the electrical equipment. First, make a preliminary judgment on the location of the fault, and then gradually narrow the scope. When performing circuit analysis, conduct a targeted investigation based on the phenomenon of the fault; after the circuit analysis is completed, you can Perform power-off inspection operations. Since the machine tool may have electrical faults such as short circuits, power-off troubleshooting should not only turn off the machine start switch, but also completely disconnect the main power supply of the machine tool, and then check the location of the fault based on the preliminary results of the circuit analysis.

(2) Classification of electrical equipment failure

Machine tool electrical equipment failures can be divided into two types: natural equipment failures and man-made failures. During the normal operation of the machine tool, the equipment components in the machine tool are often worn, aging, and invalid due to inevitable mechanical vibration, current leakage, or thermal effects of various mechanical and electrical equipment operations.

In particular, it is important to note that the power-on inspection must be performed after the power-off inspection is completed, there is no circuit, and the power supply is grounded. The power-on inspection is mainly for troubleshooting the electrical components in the machine tool, but in order to ensure the personal safety of the maintenance personnel , It can be carried out only after the motor of the machine tool is separated from the transmission part.

(3) Common diagnostic tools and methods

If you encounter a circuit open circuit fault, the most commonly used diagnostic method is the test pencil diagnosis method, which is to test each suspected fault point through the test pen, and the point where the test pen does not light is the open circuit; in addition, the fault point and the power supply voltage The investigation is generally carried out by a multimeter. The AC and DC voltage, current and resistance of each component can be measured by the multimeter, and the fault location can be initially investigated.

The multimeter diagnosis method can be divided into step-by-step measurement method and segmented measurement method. The former is to check voltage faults by reducing the scope part by part, which is similar to the upper step, so it is called step-by-step measurement, while the latter checks voltage faults part by part in turn. Therefore, it is called segmented measurement; the other method is called short-circuit method, which means that in the process of troubleshooting, short-circuit the suspected open-circuit problem by connecting a good wire. If the circuit is connected after short-circuiting, It means that there is an open circuit there, but this method cannot detect circuit problems with multiple open circuits.