Most people are now familiar with the vacuum arc furnace, including its features, applications, working principle, and precautions. However, during daily operation, small faults may occur, and users may not always know the cause. The common issues are as follows:
- Arc Formation Requires Specific Conditions: A vacuum arc requires high voltage and low vacuum, typically in the kilovolt range and below ~1 Pa. If the vacuum is too high, the arc will not form. In atmospheric conditions, arcs are easily drawn, such as in welding machines.
- Arc Depends on Vacuum Level, Voltage, and Electrode Distance: The behavior of the vacuum arc is influenced by the vacuum degree, applied voltage, and the gap between electrodes.
- Arcing in Mechanical Contacts: Mechanical electrodes switching on/off can always produce arcing. Even the smallest contactors may arc; the difference is only the arc size.
- Motor Coil Arcing: If the motor coils produce arcs, it raises concerns—but coils are insulated and generally safe.
- Open Circuit Faults: Open circuits are very common in vacuum arc furnaces, typically manifested as interrupted circuits. In some cases, open circuits can cause overvoltage, and arcs at the open point may lead to electrical fires or explosions.