1. The switching signal of PLC controls the inverter
The PLC can control the start, stop and reset of the inverter through the program; It can also control different combinations of high-speed, medium-speed and low-speed terminals of the inverter to achieve multi-stage speed operation. However, because it is controlled by switching quantity, the speed control curve is not a continuous smooth curve, and it cannot achieve fine speed regulation.
The PLC switching quantity is connected with the PLC
2. The analog signal of PLC controls the inverter
There are also some numerical command signals (such as frequency, voltage, etc.) input in the inverter, which can be divided into two types: digital input and analog input. The digital input is mostly given by the keyboard operation and serial interface on the inverter panel; The analog input is given externally through the terminal, usually through a voltage signal of 0-10V/5V or a current signal of 0/4-20mA. The interface circuit varies depending on the input signal, so the output module of the PLC must be selected according to the input impedance of the inverter. When the voltage signal scale of the inverter and the PLC is different, such as the input signal scale of the inverter is 0-10V and the output voltage signal scale of the PLC is 0-5V, or the output signal voltage scale of the PLC side is 0-10V and the input voltage signal scale of the inverter is 0-5V, because of the allowable voltage, current and other factors of the inverter and the transistor, it is necessary to connect the current limiting resistor and voltage divider circuit in series mode, adjust the inverter parameters and jumpers to change the inverter voltage and analog signalto ensure that the opening and closing do not exceed the corresponding capacity of the PLC and inverter interface circuits. In addition, care should be taken to separate the wiring when connecting the wiring to ensure that noise from one side of the main circuit is not transmitted to the control circuit.
Analog
Advantages: PLC programming is simple and convenient, the speed control curve is smooth and continuous, and the operation is stable.
Defects: In the large-scale production line, the control cable is long, especially when the DA module selects the voltage signal output, the line has a large voltage drop, which affects the stability and reliability of the system.
3. The PLC uses RS-485 communication method to control the inverter
This is one of the most commonly used methods, and the PLC uses RS serial communication instructions for programming. Advantages: The hardware is simple, the cost is the lowest, and 32 inverters can be controlled. Defects: A large amount of programming work.
4. The PLC uses RS-485 Modbus-RTU communication method to control the inverter
The RS-485 terminal communicates with the PLC using the Modbus-RTU protocol. Advantages: PLC programming of the Modbus communication method is simpler and more convenient than the RS-485 protocol-free method. Defects: PLC programming is still a large amount of work.
5. The PLC uses the fieldbus method to control the inverter
Mitsubishi drives can be built with various types of communication options, such as the FR-A5NC option for CC-Link fieldbuses; FR-A5AP(A) option for Profibus DP fieldbus; FR-A5ND option for DeviceNet fieldbus and more. Mitsubishi FX series PLC has a corresponding communication interface module to connect with it.
Advantages: fast speed, long interval, high efficiency, stable operation, simple programming, and a large number of inverters that can be connected. Disadvantages: High cost.
6. Choose extended memory
Advantages: low cost, easy to learn and use, reliable performance Defects: can only be used in a system of no more than 8 inverters.
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Reynolds inverter manual
Reynolds inverter brochure (partial)
Before installing
When unpacking, it is found that the machine has water or left water traces, indicating that the inverter has been flooded, so please do not install and use it.
When unpacking, it is found that the machine is damaged and deformed or the parts are missing, please do not install and use it, otherwise there will be fault expansion and personnel ...
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Wiring method and principle of PLC and inverter shielded wire - Reynolds
In order to avoid the interference of the control signal line between the PLC and the inverter by the space electromagnetic field, the shielding wire can be connected to the outer layer of these control signal lines to improve the anti-interference ability of the system. This kind of wiring must be noted, and only one point can be selected for the grounding point of the shield. Whether it's on the PLC side, or ...
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Reynolds soft starter problem solving
1. The soft starter does not start and the fault-free code appears, perhaps because the control power supply is not connected, the solution is to check the power supply of the control power supply to see if the circuit connection is correct.
2. The motor starts when the motor announces a hum/no start signal, perhaps because of the thyristor/module ...
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The heat dissipation method of the switching power supply
1. Transfer heat pipes for heat dissipation.
In many applications, heat generated from the base steel plate of the power module is transferred through the heat transfer components to the distant surface of the heat pipe. In this way, the temperature of the base steel plate of the power module will be equal to the temperature of the heat pipe heat dissipation surface, the temperature of the heat transfer parts, and the temperature of the two contact ...
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How to control the torque of the inverter vector according to the system - Reynolds
A brief introduction to the progress of the inverter in terms of torque:
This function adds the output voltage of the inverter so that the output torque of the motor is proportional to the square of the voltage, so as to improve the output torque of the motor. Improve the skill of insufficient torque at low speed output of the motor, and use the "vector manipulation" ...
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Reynolds drive soft troubleshooting
1. Phenomenon
(1) When starting from the beginning, it trips as soon as the speed is raised. This is a very serious phenomenon of overcurrent. The main reasons are: short circuit of load, stuck mechanical parts; The inverter module is damaged; The torque of the motor is too small.
(2) Jump when powered on, this phenomenon generally can't ...
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The water pump is controlled by a frequency converter – Reynolds
1. The constant pressure water supply of the inverter increases the comfort of water supply by 3 times
2. Constant water pressure, reducing pipe bursts and leakage by 80%
3. High efficiency and energy saving, power saving effect up to 20%-60% (depending on the actual situation)
4. The use of frequency converters can realize multi-point pressure in different time periods.
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The difference between frequency converter and power saver - Reynolds
Many people don't have a clear idea of the detailed differences and uses of AC converters and power savers. Power savers are generally divided into lighting appliances and power savers. Using high-voltage filtering and energy absorption skills, it automatically absorbs the energy of the reverse potential of high-voltage power equipment, and continuously feeds back ...
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Inverter dust handling – Reynolds inverters
1. Plan a special inverter room: When the power of the inverter used is large or the number is large, a special inverter room can be planned. The doors, windows and cable holes in the room should be sealed to prevent dust from entering; It is necessary to plan air filtration equipment and circulation channels to adhere to the normal circulation of indoor air ...
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The heat dissipation method of Reynolds switching power supply
1. Transfer heat pipes for heat dissipation.
In many applications, the heat generated from the base steel plate of the power module is transferred through the heat transfer components to the distant heat pipe surface. In this way, the temperature of the base steel plate of the power module will be equal to the temperature of the heat pipe heat dissipation surface, the temperature of the heat transfer parts, and the temperature of the two contact ...
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The item that needs to be maintained after the inverter is shut down – Reynolds
1. Use a vacuum cleaner with a plastic nozzle to thoroughly clean the inside and outside of the inverter cabinet to ensure that there is no excessive dust around the equipment.
2. Check the ventilation and lighting of the frequency conversion room, and the ventilation equipment can operate normally.
3. Check the inverter ...
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Classification of Reynolds inverter types
1. Classified according to the input voltage level
According to the input voltage level, the inverter can be divided into low-voltage inverter and high-voltage inverter, and the low-voltage inverter is common in China with single-phase 220 V inverter, three-phase 220 V inverter, and i-phase 380 V inverter. High-voltage inverters are commonly used in 6 kV, 10 kV transformers.
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The factor that causes the breakdown of the inverter – Reynolds
1. Overpressure leads to brake pipe breakdown.
The so-called overvoltage of the inverter refers to the fact that the inverter voltage formed due to various reasons exceeds the additional voltage, which is concentrated in the DC voltage of the inverter DC bus.
The overvoltage alarm generally appears at the time of shutdown, and its main ...
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Precautions for multiple motors in one inverter - Reynolds
Equipment selection
1. Inverter selection. When it comes to sizing, the first thing to consider is the operating conditions – whether one or more motors should be started or stopped at any time during the operation of the inverter.
If the motor does not need to be started at any time during the operation of the inverter, it may only be stopped or ...
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The relationship between Reynolds motion control and frequency converters
Motion control has obvious period characteristics, it is a variety of high-tech generalization, used to push industrial automation, office automation and home automation to a higher stage. Nowadays, motion control is mainly composed of variable frequency drive (VFD), electric motor, control ...
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Application misunderstandings and drawbacks of inverter and countermeasures - Reynolds
Misunderstanding: connect electromagnetic switches and electromagnetic contactors in the output circuit of the inverter
In actual use, some occasions require the use of contactors for frequency converter switching: such as when the frequency conversion is faulty, switch to the power frequency operation, or when the one-to-two method is adopted, a motor is faulty, and the variable frequency is used.
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Reynolds inverter parameter settings
The use of Reynolds inverters in industrial production is very important, in addition to speed regulation, soft start effect, the important thing is to be able to save energy. There are many functional parameters of Reynolds inverter, and there are generally dozens or even hundreds of parameters for users to choose. In practice, it is not necessary to ...
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Interpretation of Reynolds inverter models
Take the RNB2000 series inverter as an example.
The model number of the RNB2000 series 37kW inverter is: RNB2037-U
RN: on behalf of Reynolds;
B: low-voltage frequency conversion governor;
2: 2000 series;
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Misunderstanding of inverter selection - Reynolds
1. In order to save power, the inverter is selected
Many manufacturers and salesmen praise how high the power-saving rate of the inverter is, and the user also believes that it is true, and the inverter is selected at a high cost simply in order to save electricity, but the results are greatly disappointed.
Whether the inverter can save power after using it is determined by the load driven by it.
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The cause of the damage of the inverter - Reynolds inverter
What are the causes of inverter damage?
First, the heat dissipation of the inverter is not good
In fact, we all know that too high a temperature can have a damaging effect on any device, just like the human brain, too high a temperature can also burn out the brain ...
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