The Distance Between Variable Frequency Drive and Motor

1. In the industrial field, frequency inverter and motor installation distance can be roughly divided into three situations: source distance, distance and near distance. 20m within close range, 20-100m in the distance, more than 100m distance.

For the transducer installation, we need comprehensive consider the distance about the central control room, inverter, motor, minimizing the effects of harmonics, improve the control stability.

Since the inverter output voltage waveform is not sinusoidal waveform, which contain a large number of harmonic components and will make the inverter output current harmonics increases, causing the motor winding heating,vibration and noise, accelerated aging, may also damage the motor; at the same time, various frequency harmonics to space launch different program of radio interference, may also lead to other equipment malfunction. Therefore, I hope the inverter controlled motor arranged in the vicinity. However, due to the space limited for the production, they used to be a certain distance between frequency inverter and the motor.

If the frequency inverter and motor for 20m within a close distance, can be directly connected with a frequency inverter.

If the inverter and motor between 20m to 100m inverter connected in distance, need to adjust the carrier frequency to reduce harmonic and interference

If the frequency inverter and the motor is more than 100m long-distance connections, not only to moderately reduce the carrier frequency, even install output AC reactor.

2. In a highly automated factory,all the equipment can be monitored in the central control room, inverter system send the signals to the control room, the position in center of inverter control, overall control platform and inverter between, can be directly connected, through the 0-5 / 10V voltage signal and switch signal control. However, inverter high frequency switching signal of electromagnetic radiation on the weak control signal will produce some interference,so it doesn't have to be beautiful and neat, the transducer is placed in the center control room. If the distance between inverter and control center is far, you can use 4-20mA current signal and switch quantity control connection;  if the distance is farther ,you can use RS485 serial communication mode to connect; if even longer distance, can use the communication intermediate relay to 1km distance; if using of optical fiber connector,  the distance can achieve 23km. The communications cable is connected, can easily form and drive control system, thus achieving a master / slave synchronization control requirements. With the current popularity of field bus system connected to data conversion rate to rise greatly. Center control room and frequency inverter cabinet in the distance between the extended, shorten the distance between the transducer to the motor, so that a more reasonable layout to improve system performance.