Urgent help: issue with frequency conversion motor-driven mixer stopping unexpectedly
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A mixer driven by an inverter motor stops operating when the frequency is increased to 40-50 during use. It was the same several times over. However, the equipment rotates smoothly, and there are no abnormal noises during operation. Please analyze the cause of the fault.
The motor is not compatible with the mixer; the torque is too high at high speeds, causing overload protection of the frequency converter
When adjusting the frequency, check the current as well as the issue of whether the motor power matches that of the mixer.
The answers given by those upstairs are quite reasonable. Have you ever reached 50Hz before? If you did reach that frequency in the past but now experience interruptions in operation, check whether there have been any changes in medium viscosity, capacity, power voltage, etc., that could lead to an increase in the current drawn by the mixer.
Which brand of inverter doesn’t display the cause of the fault on its interface? ~~
What was said on the 4th and 5th floors makes sense: when variable frequency speed control is used, the motor frequency increases, and thus the power consumption of the mixer also increases. If the power consumed by the mixer exceeds the motor’s rated power, the motor will trip.
Check what the current of the inverter is?
I came across a pump of the JHL6-80 type, with a motor power of 22 KW and 2 poles; it experiences overcurrent when in operation. It’s not possible to install an inverter to keep the secondary current below 40A.
Variable frequency drives are used to control the speed of asynchronous motors. When selecting the capacity of an inverter, its rated current is a key factor; the capacity of the inverter should be chosen based on the maximum operating current that may occur during use. After the asynchronous motor is selected, the frequency converter should generally be chosen based on the motor’s rated current, or based on the actual current value (the maximum value) during operation of the asynchronous motor. When the operating mode is different, the methods for calculating and selecting the capacity of the inverter vary, as do the requirements that the inverter must meet. When selecting the capacity of an inverter, its rated current is a key factor; the capacity of the inverter should be chosen based on the maximum operating current that may occur during use
This is the simplest. First, check whether the frequency converter has stopped operating due to an overcurrent alarm. Second, bypass the frequency converter and use the mains power to determine what the actual operating current is. Third, consider solutions; if the current is only slightly above the motor’s rated operating current. You can just use an inverter with a slightly higher power rating. Anyway, you won’t be able to reach 50HZ anyway, and the motor won’t burn out.