Introduction：
In recent years, industrial washing equipment is mainly based on water washing equipment, and the application of frequency converters has become more and more popular. Therefore, frequency converters have brought a new technological revolution to industrial washing equipment. D71 inverter has built-in simple PLC function, which can realize automatic multi-speed, forward and reverse functions without external controller. It has a wide range of applications in the industrial washing machine industry.
Features：
D71 is a wall-mounted inverter, the power range is 0.75KW-500KW, the voltage level of the incoming line voltage is 380V-480V, and the control method is vector control without speed sensor.
D71 has a wealth of control devices, including 8 digital inputs (LI1-LI8), 2 analog inputs (AI), 2 relay outputs (TA), 2 analog outputs (AO), 5V auxiliary power supply for analog power supply Fixed input, 24V auxiliary power supply is used for digital input, all LI/TA, AI/AO can be freely programmed to define functions.
MODBUS interface is standard configuration of D71, no option is required. The D71 can be connected to higher-level automation systems via MODBUS.
Advantage：
Large starting torque, 1.5 times the torque output at open-loop 0.5Hz, with strong low-frequency load capacity;
It has the advantage of fast torque response, and when the load fluctuates, the current fluctuation is small;
Large margin design of IGBT module, suitable for long-term operation of frequent forward and reverse high current;
High speed control precision, stable speed at high frequency;
Built-in simple PLC function, no need for external washing machine controller;
It has strong environmental adaptability, and the completely independent air duct design can greatly improve the resistance to harsh environments such as oil pollution, dust and damp heat.
System Introduction：
In this system, the 7.5KW motor of the industrial washing machine is controlled by the D71 11KW inverter, the function of the washing machine controller is realized through the built-in simple PLC function, and the rapid braking and parking are realized through the braking resistor.
Technical Parameter：
| Inverter technical parameters | Device configuration | |
 Model: D71-X | Output current: 124.6A | One D71 inverter |
| Input voltage: 3-phase, 380-480V | Frequency range: 0-400Hz | 7.5KW industrial washing machine and motor |
| Input frequency: 50/60Hz ±5% | Overload capacity: 150%, 60 seconds | Braking resistor |
| Output power: 11KW | Ambient temperature: -10-40°C | |
| Output voltage: 0-480V (the maximum value is determined by the input voltage) | Protection level: IP20 | |
On Site Usage：
According to the on-site space situation, a D71 series inverter is installed in the control cabinet, and the inverter installation and on-site motor are as shown in the figure
Running Result：
The industrial washing machine 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 economic benefits are significant, and the entire investment increased by the frequency conversion control system can be recovered in more than one year.
Customer Benefits：
Built-in simple PLC function, saving customer cost;
The running speed is stable throughout the whole process to ensure the cleaning process requirements;
Noise is significantly reduced and quieter;
The economic benefits are significant, and the entire investment increased by the frequency conversion control system can be recovered in more than one year.