1. The connection is not tight, and the connection is not tightened, which results in poor contact and heats the terminal block.

    2. If the motor coil and the outlet terminal are not fastened, it may cause heat.

    3. Due to insufficient creepage distance between terminals due to dust and oil pollution, short circuit burns out.

    4. Due to insufficient creepage distance between terminals due to dust and oil pollution, short circuit burns out.

    5. Oxidation may occur on the surface of the terminal block and the terminal block, causing the resistance value of the contact part to increase and generate more heat, which will cause failure.

    6. Moisture causes insulation resistance to decrease and cause short circuit * burned

    7. Short circuit occurs when the creepage distance is less than or greater than the corresponding voltage

    Generally speaking, the three-phase terminals of motors are manufactured by manufacturers according to the regulations when they leave the factory. The insulation distance should meet the requirements. If the terminals are intact, they will not arc due to the insufficient distance. Cause a short circuit. To analyze this fault, there are two issues that should be considered on the premise that the motor terminal box is intact. One is whether the motor coils are burned out when the terminal terminals are burned out. In terms of connection terminals, the second is that the motor coils are damaged when the connection terminals are burned, so it is another matter.

    If the motor is put into use after it has been stopped for a period of time, then the possibility of moisture and terminal oxidation will be greater, and it will be burned due to heat generation due to poor contact. If this motor runs frequently and terminal blocks are burnt out during operation, it should be judged that the terminal studs are loose, and there is a period of temperature accumulation. When the humidity in the air increases, the terminal surface oxidation will also cause After the contact resistance increases to a certain extent, this phenomenon deteriorates faster and faster. In the case of a complete junction box, it is generally difficult to find, and eventually this fault occurs. Therefore, the general electrical equipment operation requirements are also specified. Regular inspections and inspections are a good way to reduce failures. There are opportunities for shutdowns. Opening the box to check can find some early signs of failure.