Multiple methods for troubleshooting power equipment faults

In daily use, power equipment is sometimes prone to malfunctions, so analyzing the phenomenon and promptly identifying the cause of the malfunction is the key to identifying power faults. The basic theory of electricians is the foundation of analysis, which combines a full understanding of the structure, principle, and performance of power devices with practical faults. Troubleshooting is an important task for maintenance personnel. In order to thoroughly eliminate faults, it is necessary to understand the cause of the fault and, more importantly, be able to analyze and solve the problem theoretically. It is necessary to have a certain level of theoretical knowledge and master the methods of troubleshooting.

There may be many reasons for power failures, but it is important to identify the main cause among the many and use methods to eliminate the problem. The same form of malfunction may have multiple causes. Among these many reasons, which aspect is causing the equipment to malfunction requires a more in-depth and careful analysis. For example, if the power equipment is used for 01 times, inspection and analysis should be conducted from multiple aspects such as power supply, circuit, motor, and load; If the power equipment has been repaired and used for 01 time, it is necessary to start the inspection and analysis of the motor itself; If the equipment suddenly fails to operate after a period of operation, it should be checked and analyzed from the perspective of power supply and control components. After the above process, the specific cause of the power equipment failure can be determined. There are several specific methods for troubleshooting power equipment:

1. Resistance testing method

The resistance testing method is a commonly used detection method. It usually refers to a method of using the resistance range of a multimeter to measure whether the motor, circuit, contacts, etc. meet the nominal values and whether they are connected or disconnected, or using a megohmmeter to measure the insulation resistance between phases and between phases and ground. When measuring, pay attention to the accuracy of the selected range and calibration table. Generally, when using the resistance method for measurement, the general practice is to first choose a low range, and at the same time, pay attention to whether the measured circuit has a circuit, and it is strictly prohibited to measure with electricity.

2. Voltage testing method

Voltage testing method refers to a method of measuring the voltage value in a circuit using the corresponding voltage range of a multimeter. Usually, when measuring, sometimes the voltage of the power supply and load is measured, and sometimes the open circuit voltage is also measured to determine whether the circuit is normal. When measuring, attention should be paid to the gear of the meter and the appropriate range should be selected to ensure that the operation is not carried out under high voltage and low range, so as not to damage the meter; When measuring DC simultaneously, pay attention to the polarity of positive and negative.

3. Current testing method

The current testing method is a common method of measuring whether the current in a circuit meets the normal value to determine the cause of a fault. For weak current circuits, it is common to measure by serially connecting the current range of an ammeter or multimeter in the circuit; For high-voltage circuits, clamp ammeters are often used for detection.

4. Instrument testing method

By using various instruments and meters to measure various parameters, such as observing waveform and parameter changes with an oscilloscope, in order to analyze the cause of faults, it is often used in weak current circuits.

5. Routine examination method

Relying on human sensory organs (such as the burnt smell, ignition, and discharge of some electrical equipment during use) and using some simple instruments (such as a multimeter) to find the cause of the malfunction. This method is commonly used in maintenance and is also the first to be adopted.

6. Replacement of original parts method

When there is suspicion of a malfunction in a certain device or circuit board, but it cannot be determined, and there are substitute parts available, a replacement test can be conducted to see if the malfunction disappears and if it can be restored to normal.

7. Direct inspection method

To understand the cause of the fault or determine the location of the fault based on experience, the suspected fault point can be directly checked.

8. Stepwise exclusion method

If a short circuit fault occurs, the fault range and point can be determined by gradually cutting off some of the lines.

9. Parameter adjustment method

In some cases, when a fault occurs, the components in the circuit may not necessarily be damaged, and the circuit contact is also good. However, due to some physical quantities being adjusted improperly or running for a long time, external factors may cause changes in system parameters or inability to automatically correct system values, resulting in the system not working properly. In this case, adjustments should be made according to the specific situation of the equipment.

10. Principle analysis method

Based on the schematic diagram of the control system, analyze and judge the signals associated with the fault, identify the fault point, and investigate the cause of the fault. Using this method requires maintenance personnel to have a clear understanding of the working principles of the entire system and unit circuits.

11. Comparative, analytical, and judgmental methods

It is based on the working principle of the system, the action program of the control link, and the logical relationship between them, combined with the fault phenomenon, to compare, analyze, and judge, reduce the measurement and inspection links, and quickly determine the range of faults.

The above methods are commonly used for power equipment troubleshooting, which can be used alone or in combination. When encountering actual power failures, they should be flexibly used in conjunction with relevant specific situations to effectively solve the problem.

Weshine Electric Manufacturing Co., Ltd.