1. Speak before you start
When it comes to faulty electrical equipment, you should not rush into action, but ask about the passage and phenomenon of the fault.
For unfamiliar equipment, you should also understand the circuit principle and structural characteristics, and follow the corresponding rules. Before dismantling, it is necessary to fully understand the function, location, connection method and relationship with other surrounding equipment of each electrical component
2. Exterior first and then interior
The equipment should be checked for significant cracks and defects, and its repair history and service life should be understood before inspecting the inside of the machine. Before dismantling, you should line up the surrounding fault factors, and determine the problem in the machine before dismantling, otherwise, blindly disassemble, or the equipment will be repaired more and more bad.
3. Mechanical first and then electrical
Only after it is confirmed that the mechanical parts are fault-free, then the electrical aspect is checked. When checking the fault of the circuit, you should use the detection instrument to find the faulty part, confirm that there is no bad contact problem, and then check the operation relationship between the circuit and the machinery in a targeted manner to avoid misjudgment.
4. Static first and then dynamic
When the equipment is not powered on, determine the quality of the buttons, contactors, thermal relays and fuses of the electrical equipment, so as to determine the fault. Energizing test, listening to its sound, measuring parameters, determining faults, and finally repairing. For example, when the motor is out of phase, if the three-phase voltage value cannot be determined, you should listen to its sound and measure each relative ground voltage alone to determine which phase is defective.
5. Clean first and then repair
For the electrical equipment with heavy pollution, first clean the buttons, wiring points, and contact points to check whether the external control keys are out of order. Many of the problems are caused by dirt and conductive dust blocks, which are often swept away once cleaned.
6. Power before equipment
The fault rate of the power supply part accounts for a high share of the whole faulty equipment, so overhauling the power supply first can often get twice the result with half the effort.
7. First pervasive and then special
Faults caused by the quality of installation accessories or other equipment faults generally account for about 50 of the common faults. The special faults of electrical equipment are mostly soft faults, which need to be measured and repaired by experience and instruments.
8. Exterior first and then interior
Don't rush to replace the damaged electrical parts just yet, and consider replacing the damaged electrical parts when you confirm that the peripheral equipment circuits are working properly.
9. DC first, then communication
During maintenance, it is necessary to check the static operation point of the DC circuit first, and then communicate the dynamic operation point of the loop.
10. Problem first and then debug
Regarding the electrical equipment with both debugging and problems, the fault should be removed first, and then the debugging must be carried out under the premise of electrical line speed.
|
More on that
|
LS inverter series and its features
LS inverter, the full name of LS communication frequency conversion governor, after supplying a variety of equipment, converts direct current into communication electricity, and changes the voltage and frequency of ordinary power supply input to control the speed of the motor, to meet different industrial needs, and then complete the energy saving and environmental protection of the automation system. ...
|
|
LS power production contactor application
LS touchers are divided into AC touchers (voltage AC) and DC touchers (voltage DC), which are used in electricity, power distribution and consumption. Toucher broadly refers to the electrical appliances that use the current flowing through the coil to generate a magnetic field in industrial electricity, so that the contacts are closed, so as to control the load.
...
|
|
LS power production PLC installation and wiring skills
The PLC should be kept away from strong disturbance sources such as electric welding machines, high-power silicon rectifiers and large-scale power equipment, and should not be installed in the same switch cabinet as high-voltage electrical appliances.
Power line, control line and PLC power line and I/O line should be separated from the wiring, barrier transformer and PLC and I/O should be selected ...
|
|
The internal accessories component of 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.
|
|
Basic introduction to transistors - LS produces electricity
A transistor is a solid-state semiconductor device with a variety of functions such as detection, rectification, amplification, switching, voltage regulation, and signal modulation. A transistor is a variable current switch that can manipulate the output current based on the input voltage. Unlike general mechanical switches (e.g. Relay, swit...)
|
|
Three-phase motor current is too high - LS power generation
First, the power supply problem
1. The power supply voltage is too high
When the power supply voltage is too high, the motor back electromotive force, magnetic flux and magnetic flux density all increase. Since the magnitude of the iron loss is proportional to the square of the magnetic flux density, the iron loss increases, resulting in overheating of the core. And the increase in magnetic flux causes ...
|
|
Inverter carrier frequency adjustment method - LS power generation
A． The output voltage of the SPWM inverter is a series of pulses, and the pulse frequency is equal to the carrier frequency.
B. In the current of the motor, there is a harmonic component with a strong carrier frequency, which will cause the vibration of the motor core and announce the noise. If the frequency of the noise is the same as that of the motor core.
|
|
The difference between servo drive and frequency converter - LS produces electricity
Servo drives and frequency converters are defined differently
The driver, also known as servo manipulator and servo amplifier, is a kind of manipulator used to control servo motors, and its function is similar to that of a frequency converter acting on a general communication motor. It is part of the servo system, mainly used for high-precision positioning ...
|
|
The role of the inverter - LS generates electricity
1. The inverter can adjust the power of the motor and complete the variable speed operation of the motor, so as to achieve the purpose of saving electricity. For example, it is reflected in the centrifugal fan and water pump, when the centrifugal fan and water pump use the frequency converter, the operator can convert the frequency to regulate the speed, and can easily control the flow rate according to the need, so as to save ...
|
|
The touch screen controls the inverter steps
1. The touch screen is controlled by PLC inverter
1. At present, the general control of the inverter needs to use PLC to communicate with the inverter, read the information of the inverter, and then the touch screen communicates with the PLC in order to complete the control of the inverter to start, stop, and monitor the operation of the inverter.
|
|
The main structure of LS power AC contactor
The operating principle of the contactor is: when the contactor coil is energized, the coil current will generate a magnetic field, and the generated magnetic field will make the static iron core attract the moving core with electromagnetic attraction, and drive the communication contactor point action, the normally closed contact is disconnected, and the normally open contact is closed, and the two are linked. When the coil is de-energized ...
|
|
The advantages of the inverter in practical application - LS power generation
With the continuous progress of industrial automation, inverters have also been widely used, energy conservation and environmental protection as the core of China's industrial economy, in the direction of the sustainable development of China's industry, but also useful to promote the sustainable development of China's inverter profession, so that I ...
|
|
Requirements for the use of starting inverter motors - LS power generation
Frequency conversion motor refers to the motor that runs continuously with 100% rated load in the range of 10%-100% rated speed under standardized environmental conditions, and the temperature rise will not exceed the allowable value of motor calibration.
Communication contactors are not necessary for frequency converters and are built in, ...
|
|
Classification of the nature of DC power supply of inverter - LS power generation
A frequency converter is actually an inverter. It starts by turning alternating current into direct current. Then the direct current is switched on and off with electronic components. Becomes alternating current. Thyristors for general inverters with larger power. And set up a device with adjustable frequency. Make the frequency adjustable within a certain range. Used to control ...
|
|
The inverter reads the rated data method - LS power generation
The technical parameters of the inverter (Variable-frequency Drive, VFD) are divided into the input side and the output side. The technical parameters of the input side of the VFD include input voltage, number of phases and frequency; Output-side technical parameters include additional output voltage, additional current, additional capacity, capacity, frequency accuracy, etc.
|
|
Relationship between motion control and frequency converter
Motion control has a significant period characteristic, it is a combination of a variety of high-tech to push industrial automation, office automation and home automation to a higher stage. At present, the motion control is mainly composed of three parts: inverter, motor and controller.
...
|
|
A brief description of the K120S series plc
K120S series PLC product is a unit PLC product introduced to the market by LS in 2004, which has laid a solid foundation in the low-end small machinery supporting industry with its high-performance price ratio. Relying on some special functions of the product, it has also won some industry praise.
...
|
|
The basic principle of motor protector selection - LS power production
The fundamental method of motor protector selection
At present, there is no unified standard for motor protectors on the market, and almost every manufacturer has its own type standard. In order to meet the needs of different customers, manufacturers derive many products with different uses, and a wide range of products for the majority of users to choose ...
|
|
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 difference between multi-function and general-purpose inverters
Multi-function inverters need to meet the following two conditions:
First, it can be driven by constant torque load, regardless of the type of machine, and can ensure continuous operation even if the load fluctuates greatly. If the above conditions are not satisfied, the inverter will be easy to stop, difficult to start again, and resistant to ...
|
|
Contact
working hours
