1, first static, then dynamic

    The so-called static inspection is an inspection performed before the induction melting furnace is not energized. When it is confirmed that the static check is correct, the power can be energized for dynamic check. If abnormal conditions such as smoke or flicker are found, you should turn off the machine quickly and perform a static check again. This will prevent the induction melting furnace from being energized when the situation is unclear, causing undue damage.

For the measurement instruments used in the current maintenance, only the functional online test and static characteristic analysis can be performed on the components on the circuit board. If the faulty circuit board is finally completely repaired, it must be installed back to the original circuit for inspection. Only then. In order to obtain the correct result of this inspection process, to judge whether the circuit board with the replacement of the electrical and electronic components is repaired, it is best to check whether the auxiliary power supply of the induction melting furnace is correctly supplied to the relevant circuit board as required, and the circuit board. Whether the interface plug-ins on the board are securely inserted. And to eliminate the impact of circuit board peripheral circuit failure, in order to correctly guide the maintenance work.

2, first clean, after repair

    For inductive melting furnaces with heavy pollution, first clean the panel buttons, terminals, and contacts, and check if the external control keys are malfunctioning. When inspecting the inside of the induction melting furnace, it should be emphasized whether the inside of the induction melting furnace is clean. If there is dust, dirt, spider web or excess solder, welding oil, etc. between the components, leads and traces in the induction melting furnace, it should be first Clear and then overhaul, which can reduce natural faults and achieve twice the result with half the effort. Practice shows that many faults are

It is caused by dirt, dust, and foreign matter. Once it is cleaned or cleared, it will automatically disappear.

3, the first power circuit, the rear function circuit

    The power supply is the heart of the induction melting furnace. If the power supply is not normal, it is impossible to ensure the normal operation of other parts, and there is no way to check other faults. According to experience, the failure rate of the power supply part accounts for the highest proportion in the whole machine. Many faults are often caused by the power supply. Therefore, the maintenance of the power supply circuit can often get twice the result with half the effort. The maintenance of the induction melting furnace should be based on the maintenance. The circuit power supply part, the control power supply part, the maintenance control circuit, the trigger circuit part, and finally the order of the display parts. This is because the power source senses the source of energy that can be used by various parts of the melting furnace, and the control circuit is the basis for normal operation.

4, first universal, after special

    In the absence of a clear understanding of the fault location of the induction melting furnace, do not blindly adjust some of the adjustable components in the induction melting furnace to avoid artificially complicating the obstacles. When the protection circuit components such as fuses or current limiting resistors in the machine are hit or burned, it is necessary to carefully check whether there are any problems with the surrounding circuits. After confirming that there is no problem, replace them and restore the power supply. Faults caused by the quality of components or external factors generally account for 50% of common faults. The special faults of induction melting furnaces are mostly soft faults, which are measured and repaired by experience and instrumentation. According to the common characteristics of induction melting furnaces, common faults with universality and regularity are eliminated, and then special circuits (including some special components) are inspected. In order to gradually reduce the scope of the fault, from face to point, to achieve the effect of shortening the repair time.

5, first peripheral, then replace

    After determining the damaged components, do not rush to replace them. After confirming that the peripheral circuits are normal, consider replacing the damaged electrical components. When inspecting an integrated circuit, when the voltage of each pin of the integrated circuit is abnormal, do not rush to replace the integrated circuit. Instead, check the peripheral circuit first, and then consider replacing the integrated circuit after confirming that the peripheral circuit is normal. If you do not check the peripheral circuit, blindly replacing the integrated circuit can only cause unnecessary losses, and now there are more pins on the integrated circuit.

If you do not pay attention, it will be damaged. It can be seen from the maintenance practice that the failure rate of the peripheral circuit of the integrated circuit is much higher than that of the integrated circuit.

6, first troubleshoot, then debug

    In the overhaul, circuit faults should be eliminated before debugging. Because debugging must be done under normal circuit conditions. Of course, some faults are caused by improper debugging. At this time, it is only necessary to directly debug and return to normal. Be sure to pay attention to the quality of the solder when replacing components, and do not cause solder joints. In addition, the welding time should not be too long, so as not to damage the components and cause unnecessary economic losses. Multiple soldering of electrical and electronic components can easily cause copper foil to be removed from the board

Fall off. After replacing the components, the foreign matter in the induction melting furnace should be cleaned up in time. The wiring and connectors should be re-examined and installed in place to avoid other human failure.

7, first DC, then exchange

    During the inspection, the inspection of the electronic circuit must first detect the static working point of the DC circuit and then detect the dynamic working point of the AC circuit. DC and AC here refer to the DC and AC circuits of the electronic circuit. These two loops are complementary, and the AC loop can work normally only if the DC loop is normal.

9, first no power measurement, after power test

    First, the induction melting furnace is statically inspected without being energized. If it is normal, the induction melting furnace is dynamically inspected while being energized. If the power is turned on immediately, it may artificially expand the fault range, burn more components, and cause undue losses. Therefore, before the fault-induced melting furnace is energized, a static check must be performed, and the power can be detected under static normal conditions.

9, first shared circuit, rear unit circuit

    When the common circuit of the induction melting furnace fails, its energy and information cannot be transmitted, and the performance of each unit circuit is degraded and the function is lost. If the power supply of an induction melting furnace fails, the entire system cannot operate normally, and the energy and information transmitted to various unit circuits cannot be realized. Therefore, in the inspection, the order of the shared circuit and the rear unit circuit should be followed, and the fault of the induction melting furnace can be quickly and accurately eliminated.

The fault of the induction melting furnace is manifested as diversity. If any faulty induction melting furnace is overhauled, the fault phenomenon, cause, overhaul, skill, and experience should be recorded on a special notebook to accumulate maintenance experience and The self-experience L rises to the theory under the guidance of the theory, to achieve specific failure analysis, in order to accurately and quickly eliminate the fault. Only in this way can you cultivate yourself as an expert in troubleshooting the induction melting furnace.

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