The screw extruder control system using D71 inverter has been put into operation for more than three years, and has achieved good economic and social benefits:

• The control device operates reliably, has good environmental adaptability, can resist harsh environments such as oil pollution, dust and damp heat, and has a low failure rate; 

• Excellent current limiting characteristics, strong overload capacity, can effectively reduce frequency conversion overload, overcurrent protection, and maximize production continuity; 

• The speed control precision is high, and the production products are more in line with the requirements;

• The system has high speed regulation accuracy, which is convenient for on-site personnel to operate.