he following parameters should be taken into account when choosing a frequency converter: 

—Power: more high-power motor on the selection of high-power inverter. But for special occasions, such as high temperature and high altitude, it will cause the capacity reduction of the frequency converter, and the frequency converter is easy to enlarge one gear. 

— Current: The rated current of the frequency converter is larger than the maximum current of the motor operation, which is generally marked on the nameplate. 

—Power supply voltage: general low-voltage inverter has single-phase 220-240V, three-phase 380-480V power supply, etc., specific selection, rated according to the actual demand. 

The following parameters should be taken into account when choosing a frequency converter: 

Power  

Choose high-power inverter for high-power motor. But for special occasions, such as high temperature and high altitude, it will cause the capacity reduction of the frequency converter, and the frequency converter is easy to enlarge one gear. 

Current 

The rated current of the frequency converter is larger than the maximum current of the motor operation, which is generally marked on the nameplate. 

Supply voltage 

General low-voltage inverter has single-phase 220-240V, three-phase 380-480V power supply, etc., the specific selection is rated according to the actual demand. 

Inertia of load 

Some occasions, such as most ventilation pipes, do not require the motor to stop in time, and some transmission belts require the motor to stop in time, so it can also be used as a reference condition for the purchase of frequency converters. 

A frequency converter can control more than one motor. This application is often referred to as "one drag many".  It has operated for years and rarely fails. However, the frequency converter should pay attention to the following points: 

—the control mode must be linear V/F control; 

— one drag is only used in the motor speed adjustment without strict requirements; 

— The total rated current of each motor should be less than the rated current of frequency conversion; 

— Each motor shall be equipped with independent thermal relay; 

— The power of each motor should be consistent as far as possible; 

— The physical characteristics of each output loop should be as small as possible, including: 

— motor characteristics, such as speed; 

— cable characteristics, such as cross-sectional area, length, material. 

— If the motor characteristics are basically the same, and the cable length is close to the limit length allowed by the frequency converter, methods such as increasing the outgoing reactor, reducing the switching frequency and appropriately increasing the frequency converter can be adopted.