1. Be "confident"
It is necessary to fully understand the principles of some typical circuits and be familiar with them. Guangzhou Kewo Training Center believes that drawings are dead, and the thoughts in the head are alive, able to make analogies, able to reason, and able to touch analogies. For example, switching power supply, always inseparable from oscillation circuits, switch tubes, switching transformers, etc., to check whether the circuit vibrates, whether the capacitor is damaged, whether the triode, diode is damaged, no matter what switching power supply is encountered, the operation is almost the same, no need to force a circuit diagram; for example, the single-chip microcomputer system, including crystal oscillator, three buses (address line, data line, control line), input and output interface chips, etc., are also inseparable from these scales; Even though it is ever-changing, reasoning on the basis of "shortness" and "shortness" and "deficiency" can also have a clue, analyze it in detail, and make it clear. After practicing good analysis and reasoning, even if you encounter a device that you have never seen before, you can only understand it from the principle.
2. Pay attention to the order of maintenance
Only by paying attention to the maintenance sequence can we find the shortest way to deal with the problem, so as to prevent indiscriminate stabbing and dismantling, and the repair cannot be completed, which will lead to the expansion of the problem. Guangzhou Kewo Training Center holds circuit board repair training courses all year round, and starts on time on the 10th and 25th of each month. Repair is like a doctor treating a disease, and it also pays attention to "looking, hearing and asking". "Look" is to check the appearance of the faulty board, to see if there are obvious traces of damage on it, whether there are components burned black, bursting, whether the circuit board is broken and leaked due to corrosion, whether the capacitor is leaking, whether there is any rise on the top, etc.; "Sniff" sniffs with your nose to see if there is a burning smell of something, where the smell is announced; "Ask" is very important, to ask the person in detail, the situation at the time of the equipment failure, from the situation to reason about the possible fault parts or components; "Cut" means to use certain testing instruments and means, divided into two situations, energized and unenergized, to check the resistance, voltage, waveform, etc. of circuit parts or components, compare and test the good and bad circuit boards, and investigate the differences in parameters.
In fact, there are many problems that you can deal with without even using a multimeter, and the circuit diagram is naturally free.
3. Be longer than the general section rule.
Generally, after the accumulation of certain repair experience, it is necessary to analyze the cause of each component damage longer than the general section, is the operation improper? Lack of maintenance? Unreasonable design? Poor component quality? Natural aging? With these analyses, the next time you encounter the same kind of problem, although it is not the same circuit board, you will have a little bottom in your heart. For example, when I encountered a Cincinnati machining center that was good and bad, the supplier took measures such as reinstalling the software, reducing harmonic disturbances, and removing all the boards to reproduce the problem on other good machines, and finally did not deal with the problem after a month. Because I have repaired a lot of computer motherboard faults, I found that there are many good and bad times are problems with the capacitors on the motherboard of the previous year, I think this is the same for the control board of the machining center, so all the capacitors on the board were replaced, and the problem was dealt with in only one hour.
4. Be good at finding materials
Since the advent of the Internet, it has become very easy to find materials. Almost all of the equipment principles that you don't understand and the circuit principles you don't understand can be found on the Internet, and all IC materials can be found on the Internet. In the past, it was said that the master led the apprentice, and whether the apprentice learned well or not depends on whether the master has the heart to lead. Now you don't need it, with the Internet, your masters are all over the world, and there are all kinds of masters. Of course, if the education is not high, English is a ditch in front of us, and many things must be understood by having a foundation in English, for example, many IC materials are in English. But with Kingsoft Word Tyrant, you have this professional foundation, and many things are even guessed, and you can understand that they are not far from ten. With useful materials, no pictures are the same as having pictures, no big deal.
5. Have the necessary testing equipment
If you're making repairs your own business, a certain investment in equipment is necessary. Soldering iron, multimeter, commonly used disassembly and assembly tools, the brand should not be too bad. (My multimeters are all FLUKE189 of more than 4,000 oceans, hehe!) If you can, get a 100M dual-trace oscilloscope, and if you can, put an online repair tester.
|
More on that
|
Meaning and classification of LS Electronic Motor Relay (EMPR).
The Electronic Motor Relay (EMPR) is a digital motor maintenance relay with an MCU that has a compact and compact form factor that can be combined directly with a contactor. Through the implementation of real-time data processing, high reliability and high precision can be completed, and it can pass through phase loss, reverse, unbalance, stalled rotor, connection...
|
|
Precautions for the selection of peripheral equipment for LS power inverter
The peripheral equipment of the inverter mainly includes cables, contactors, air switches, reactors, filters, braking resistors, etc. Whether the selection of the peripheral equipment of the inverter is correct and suitable also directly affects the normal operation of the inverter and the service life of the inverter.
|
|
Inverter circuit structure - LS generates electricity
The main circuit is the power replacement part of the power supply for the asynchronous motor, and the main circuit of the inverter can be roughly divided into two categories: the voltage type is to change the DC of the voltage source to the communication of the DC port of the inverter, and the filter is the capacitor. The current type is to change the DC of the current source to the communication ...
|
|
The role of the inverter's braking resistor - LS generates electricity
1. Maintain the inverter from the damage of regenerative electricity
In the process of rapid shutdown of the motor, because of the inertia, a lot of regenerative electric energy will be generated, if this part of the regenerative electric energy is not consumed in time, it will directly act on the DC circuit part of the inverter.
|
|
The five stages of mastery of PLC technology
One. Logical stage
The so-called logical stage is to be able to complete the general logical planning in the relay system, since it is a relay system, so the knowledge of power drag is the foundation of this stage. I personally summarize that the root of learning the relay system lies in the word "grab", the relay system ...
|
|
Practical common sense in the inverter industry - LS inverter
1. The low-voltage fuse cannot be used as an overload maintenance of the motor.
2. The additional voltage of the fuse must be greater than or equal to the operating voltage of the distribution line.
3. The additional current of the fuse must be greater than or equal to the ...
|
|
The internal accessory component of the circuit breaker - the power production circuit breaker
1. Auxiliary contact: the contact mechanically linked with the main circuit of the circuit breaker and the closing mechanism is mainly used for the display of the circuit breaker and the closing status, and is connected to the control circuit of the circuit breaker through the opening and closing of the circuit breaker to control or interlock its related electrical appliances. For example, output to signal lights, relays, etc.
|
|
Introduction of LS electric power contactors
How LS Contactor Works:
Generally, after the contactor coil is energized, the entire coil current will generate a magnetic field, which will make the core inside have electromagnetic attraction to attract the core, and let their communication contactor point action normally closed contact disconnect, or close, which ...
|
|
The torque of the inverter is directly used as the controlled quantity mode - LS generates electricity
VVVF frequency conversion, vector control frequency conversion, and direct torque control frequency conversion are all one of the AC-DC-AC frequency conversion. Its common disadvantages are low input power factor, large harmonic current, large demand for energy storage capacitors in DC circuits, and renewable energy can not be reflected back to the grid, that is, it cannot carry out four-quadrant operation.
|
|
LS power production contactors are used in this area
LS contactors are divided into AC contactors (voltage AC) and DC contactors (voltage DC), which are used in electricity, power distribution and consumption. Contactor in a broad sense refers to the electrical appliances that use the current flowing through the coil to generate a magnetic field and close the contact to control the load in industrial electricity.
...
|
|
LS power generation installs the switching power supply step
1. Confirm the location of the device
Before the equipment switches on and off the power supply, it is necessary to confirm the location of the equipment, and generally require the equipment to be in a ventilated, boring, non-corrosive gas and dust-free place.
2. Equipment holder
The fixed base of the switching power supply is fixed on the orientation of the equipment, and the general ...
|
|
Precautions for the peripheral configuration of the inverter - LS generates electricity
(1) When the inverter is connected to the power grid of large-capacity power transformer (more than 500kVA), perhaps the same power transformer is connected with a thyristor converter without using a commutation reactor, or when there is a switching capacitor bank for power improvement in the same power grid, an AC reactor or DC reactor should be equipped.
|
|
Inverter control motor operation method - LS power generation
When the main circuit of the inverter is connected to the power line, in order to control the operation of the motor, it is also necessary to connect the relevant terminals to the peripheral control circuit, and set the parameters of the inverter's starting method to the external operation form.
The inverter controls the motor to run, and there are two common methods, which are to turn on the ...
|
|
Single-table driver for HLP2B
|
|
Inverter installation environment requirements - LS power generation
Inverter device environmental requirements 1: operating temperature;
The inverter is a high-power electronic component, which is easily affected by the working temperature, and the product is generally required to be 0-55 °C, but in order to ensure that the work is [safe] [complete] [can be] [reliable], the use should be considered to leave room for control, and the control is at 40 ...
|
|
Elements of LS power inverter operation
1. Physical environment
(1) Temperature factor
Temperature has a huge impact on the lifetime and reliability of the electronic components inside the inverter. When using the inverter in a high operating temperature environment, it is necessary to take additional cooling measures to ensure that the ambient temperature is stable in the inverter.
|
|
Precautions for the coordination of inverter and PLC - LS produces electricity
As an alternative to traditional relays, PLC is widely used in various fields of industrial control. Because the PLC can be used to change the control process with software, and has the characteristics of small size, sensitive assembly, simple programming, strong anti-disturbance ability and high reliability, it is especially suitable for operation in harsh environments. ...
|
|
Introduction of LS PLC programming software
LS PLC programming software is a professional PLC programming assistant tool, providing excellent interface, which can carry out PLC programming operations such as online modification, debugging and self-diagnosis, packing and debugging, etc., compatible with LG Master-K series and LG MASTER-K series, which can make you in the process of processing in a timely manner.
|
|
Precautions for inverter installation tips - LS power generation
When the line power supply exceeds the driver's kV-A rating by 10 times, add a line reactor.
A 3% impedance line reactor should be used to reduce power line transients caused by capacitor switching, line notching, DC bus overvoltage tripping, and inverter overcurrent and overvoltage conditions. Line...
|
|
Introduction to inverter self-learning motor - LS power generation
1. What is a self-learning motor of inverter?
Enter the motor nameplate (voltage, current, Hz rating) in the inverter parameters, and then the inverter actively measures other parameters of the motor.
Second, why should the inverter learn by itself?
|
|
Contact
working hours
