Frequency converter
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A Mitsubishi A800 inverter with a load of 500 kilowatt motor. The current is more than 700 amperes during normal operation. The instantaneous current dropped to 60 and returned to more than 700 in one second. This happened three times and the rear shaft bearing of the motor was burned. The inverter did not alarm. Can you experts help analyze the reason?
The bearing is broken, causing the rotor to jam instantly. The current decreases instantaneously, and then due to the magnetic field force, it operates normally again instantaneously.
Answer from Floor 3: The bearing is broken and the motor torque increases. Logically speaking, the current should increase first and cannot decrease.
Answer from Floor 3: The bearing is broken and the motor torque increases. Logically speaking, the current should increase first and cannot decrease.
Yours is a DCS feedback signal (current indication), and it has a maximum range limit!
It's current feedback. Why does the rotor stuck current decrease?
If there is no problem with the frequency converter, check the peripheral control. . . . . .
You can look at the trend of RPM, and what process you are using, and combine it with the analysis.