Reduces EMI interference
The metal shell is used as a shield to reduce the interference of external electromagnetic field radiation. To reduce electromagnetic interference from the power line input, an EMI filter is added to the power supply input.
At the output, capacitors with good high-frequency performance and low ESR are used
It is best to use aluminum or tantalum electrolytic capacitors with polymer solid electrolyte as output capacitors, which are characterized by small size and large capacitance, low ESR impedance at high frequencies, and large allowable ripple current. It is most suitable for high-efficiency, low-voltage, high-current step-down DC/DC converters and DC/DC module power supplies as output capacitors.
Frequency synchronization with the product system is adopted
In order to reduce the output noise, the switching frequency of the power supply should be synchronized with the frequency in the system, that is, the switching power supply adopts the frequency of the external synchronous input system, so that the switching frequency is the same as the frequency of the system.
Avoid interference between multiple module power supplies
There may be multiple module power supplies working together on the same PCB. If the module power supply is unshielded and close together, it may interfere with each other and increase the output noise voltage. In order to avoid such mutual interference, shielding measures can be adopted or appropriately distanced away to reduce the interference of their mutual influence.
Add LC filter
In order to reduce the ripple and noise of the module power supply, LC filters can be added to the input and output terminals of the DC/DC module.
Increase LDOs
The addition of a low-dropout linear regulator (LDO) after the output of the switching power supply or module power supply can greatly reduce the output noise to meet the needs of circuits with special noise requirements, and the output noise can reach the μV level.
Since the differential voltage of the LDO (the difference between the input and output voltage) is only a few hundred mV, the output of the switching power supply is slightly higher than that of the LDO by a few hundred mV to output the standard voltage, and the loss is not large.
An active EMI filter and an active output ripple attenuator are added
Active EMI filters attenuate common-mode and differential-mode noise from 150kHz to 30MHz and are particularly effective at attenuating low-frequency noise. At 250kHz, it can attenuate 60dB common-mode noise and 80dB differential-mode noise, and the efficiency can reach 99% at full load.
The output ripple attenuator can reduce the output ripple and noise of the power supply by more than 30dB in the range of 1-500kHz, and can improve the dynamic response and reduce the output capacitance.
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Tianyi switch - the difference between high-voltage load switch and high-voltage isolation switch
1. The high-voltage load switch can be broken with load and has the function of self-extinguishing arc, but its breaking capacity is very small and limited.
2. The high-voltage isolation switch is generally not able to break with load, there is no arc extinguishing cover in the structure, and there is also an isolation switch that can break the load.
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What are the common problems of Tianyi switch - disconnector?
1. What are the common faults?
Answer: The common faults of the disconnector are: (1) The contact part is overheated. (2) Porcelain insulation damage and flashover discharge. (3) Refuse to pull and close. (4) Wrong pulling and closing.
2. The overheating of the contact part of the disconnector during operation is caused by ...
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Overview of limit switches and their functions - Tianyi limit switches
An overview of limit switches
Limit switch is a kind of mechanical orientation and electronic control interface, the mechanical action into electrical signals, is suitable for industrial environment of a common electromechanical and electrical components, through the contact way to detect the object, the existence and so on. It is possible to control the device's ...
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Tianyi switch - the operation precautions of the disconnector switch
(1) Before operation, check that the circuit breaker (switch) is in the opening position accordingly to prevent the isolation switch from being pulled and closed with load.
(2) There is a locking device to prevent misoperation between the knife switch, the grounding knife switch and the switch, and the reverse operation must be carried out in order. If it is locked and cannot be operated, ...
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Tianyi switch - the operation method of dual power automatic transfer switch
First, first place the dual power supply on the adjustment table, and the phase wire and the neutral wire (neutral line) are docked in place, and can not be connected wrongly.
Second, after the line is connected, it is necessary to check the installed line, and then turn on the main switch of the debugging station to turn on the common and standby working power supply.
Three, when the double ...
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Tianyi switch - the role of low-voltage isolation switch
1. Through the isolation switch, it plays a good insulating role, so that the whole circuit can be safe and secure, and the maintenance personnel or staff also have enough ability to repair the circuit.
2. At the same time, the low-voltage isolation switch can also change the operation mode of the circuit, which is used in the power plant or gas plant.
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Tianyi switch - dual power supply automatic transfer switch operating procedures
1) When there is a power outage for any reason and the power cannot be restored in a short period of time, the backup power supply must be activated
1. Cut off the circuit breakers of the mains power supply (including the circuit breakers of the control cabinet in the distribution room, and the mains power supply cut-off of the dual power switching box), and pull the double-cast anti-reverse switch to the side of the self-provided power supply to ensure that the power supply is protected.
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Tianyi switch - what are the differences between limit switches and proximity switches?
First, the characteristics are different
1. Limit switch: The limit switch has the characteristics of small size, multiple functions, high precision, adjustable limit, strong versatility and easy maintenance, installation and adjustment.
2. Proximity switch: The proximity switch has the characteristics of a limit switch, and at the same time has the sensing performance.
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Q&A on Cam Switches and Load Disconnectors (11-21)
Q11: What is the maximum number of connecting rods for the rear mounting of P1 and P3?
A: Up to 4 sections can be added, each section is 25mm.
Q12: Does the P switch with SVB in the model come with PE grounding and N-wire terminals?
A: P switch models with SVB are equipped with PE grounding and ...
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Tianyi switch - what is the function of high-voltage load switch
1. It can isolate the power supply, with a significant disconnection point, and is mostly used for fixed high-voltage devices;
2. It has arc extinguishing equipment and a certain opening and closing rate, and can pass through the normal working current and the specified short-circuit circuit in the case of closing;
3. It is forbidden to connect and cut off the circuit with load, ...
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Tianyi switching power supply troubleshooting
1. Check the key points:
1) Whether the voltage at point B is 310V.
2) Whether the 15V voltage is normal.
3) Whether the voltage at point C is greater than 14V.
4) Whether the SS terminal of (8) pin IC6 is higher than 10V, whether the SD terminal of pin (10) is lower than 0.6V, and whether there is a square wave transmission at pin 13 and pin 14 ...
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Tianyi switch - 5 methods to suppress ripple in switching power supply
1. Increase inductance and output capacitance filtering
According to the formula of the switching power supply, the current fluctuation in the inductor is inversely proportional to the inductance value, and the output ripple is inversely proportional to the output capacitance value. Therefore, increasing the inductance and output capacitance can reduce ripple.
In the same way, the output ripple is the same as the output ...
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Tianyi switch - the classification of dual power transfer switches
It is mainly divided into ATS and STS.
STS static toggle switch
STS (Static Transfer Switch), also known as static transfer switch. The STS automatically switches to the second channel to supply power to the load after the first channel fails.
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Tianyi switch - what does the 2P3P of the air switch mean
2P means two poles, which means that this air switch has two connection ports, one to connect to the neutral wire and one to the live wire, which is suitable for single-phase circuit connection, or can also be used to connect two-phase power supply in a three-phase circuit.
3P is the meaning of three poles, there are three connection ports, and all of them are ...
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Tianyi button indicator - button indicator induction circuit fault and solution
First, the reason for the fault of the induction circuit of the switch button indicator
1. Aging of circuit board: The circuit board of the switch button indicator induction circuit board may be aged if it has been used for too long, resulting in leakage in the circuit, and then the induction failure of the indicator light.
2. Sense ...
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Tianyi switch - the difference between fuse and air switch?
1. In addition to the short-circuit protection function of the fuse, the air switch can also realize the overload protection of the circuit.
2. The fuse is a one-time protection device, which must be replaced once it is blown and is very troublesome, so its reusability rate cannot be compared with the air switch. ...
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Tianyi switch - the air switch is always the reason for tripping
1. The current value of the air switch is too low, and the load power is greater than the rated power of the air switch.
2. The load joint is not firm, and the joint is not compressed.
3. If there is a short circuit in the line, check whether the electrical plug is dry.
4. The line is aging and leaking, resulting in both the live wire and the neutral line.
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Tianyi switch - common faults and treatment methods of switching power supply
First, the repair method
The maintenance of a switching power supply can be carried out in two stages
(1) When the power is cut off, it is "Look, Listen, Listen, Measure"
Look: Open the power box, check whether the wire is disconnected, look inside the power supply, and find that the PCB substrate of the power supply is scorched or the components are cracked.
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Tianyi switch - the term introduction of limit switches
Pre-stroke - indicates the distance or angle at which the actuator on the limit switch must move before tripping the switch contact
Operating Point - Indicates the position of the actuator when the switch contact is moved to the working position
Release Point - Indicates the position of the actuator when the contact returns to its original state
Differential - ...
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Tianyi switch - introduction to the types and characteristics of limit switches
Conventional domestic travel switch
LX19-001/111 in the LX19 series, LXK3-20S/T in the LXK3 series, JLXK1 series JLXK1-111/411/511 in the conventional travel switch are the most representative.
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