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Daily Electronics Knowledge Lesson 46- Varistors, MOVs

  Varistors and MOVs are both protection elements, mainly used for circuit overvoltage protection. However, there are differences between the two in terms of materials, operating principles, and usage scenarios.

Varistors are voltage-controlled components that can produce a change in resistance when passing current.


Advantages:Fast response time, can withstand high pulse current.


Disadvantages:Higher leakage current, sensitive to temperature.


Varistors are commonly used to suppress arcing, electrical noise, surges, and to protect circuits from overvoltage and overcurrent.


MOVs, or Metal Oxide Surge Arresters, are gas discharge tubes designed to operate under overvoltage conditions.


Advantages of MOVs: Higher arc extinguishing capability


Disadvantage: longer response time


MOVs are usually used in parallel in circuits to prevent overvoltage or overcurrent conditions.


In common combinations.

Varistors are usually used in conjunction with circuits such as microprocessors, large-scale integrated circuits, precision electronics and communications equipment to suppress electrical noise and protect electronic components from overvoltage and overcurrent.


MOVs are commonly used in electric power, communications, electronic equipment and other fields, as line protection and overvoltage suppression devices.


Varistors and MOVs are widely used in the electronics industry, the choice of which components to use depends on the specific application scenarios and needs.

Daily Electronics Knowledge Lesson 45- DIN 41612

  DIN 41612 is a stainless steel electrode, often referred to as chromium-molybdenum alloy 41612 electrode. It is an all-position weldable electrode suitable for welding carbon steel, A3 steel and most dissimilar steels.

The principle of DIN 41612 is mainly to use its flux skin to make a transition that connects the weld core (metal) to the iron (ferrous) in the molten pool. There are four forms of transition: slag reaction transition, spatter transition, gas-slag mixture transition and intermetallic compound transition. These processes allow for stable arc combustion, droplet transition and solidification of the metal in the molten pool to form a continuous, smooth weld.


The advantages of DIN 41612 mainly include good mechanical properties and weldability, and it is widely used for welding various types of steel structures and a large number of dissimilar steels in various environments. In addition, it is widely used in the petrochemical, structural steel and heavy machinery manufacturing industries.


However, DIN 41612 has some disadvantages. As it is used to weld important steel structures, it requires very skilful welding processes and specifications, otherwise the quality of the weld may be compromised. In addition, this electrode consumes more power for a DC welder than an AC welder, so you need to pay attention to the power source power.


A common pairing of DIN 41612 is GTAW (TIG) and SMAW (Manual Arc Welding), which can be applied by manual arc welding. In terms of industry, DIN 41612 is mainly used in heavy industries such as manufacturing, petrochemical, boiler and energy industries.


Overall, DIN 41612 is a very important stainless steel electrode for industries that need to weld important structures, and its stringent technical and specification requirements cannot be ignored.

Daily Electronics Knowledge Lesson 44- GPIB & Communications

  GPIB & Communications is the GPIB communications protocol, a standard for communication between instrumentation. This protocol allows different instruments and devices to communicate via the GPIB interface for automated test and measurement.

Principle: The GPIB communication protocol is based on the IEEE 488 standard and enables communication between instruments and devices through the GPIB interface. Each instrument and device has a unique ID number through which different devices can be identified and controlled. Through the GPIB interface, instruments and devices can exchange data and control commands, thus realising automated tests and measurements.


Advantages: The advantages of the GPIB communication protocol include ease of use, flexibility, and ease of expansion. It simplifies the test and measurement process by allowing different instrumentation to communicate through a single unified interface. In addition, the GPIB interface provides error detection and correction features that ensure reliable and accurate communications.


Disadvantages: Disadvantages of the GPIB communication protocol include slower communication speeds and the need for manual intervention. Since GPIB communication is based on a physical connection, communication speed is limited by the hardware device. In addition, it is not suitable for highly automated application scenarios because it requires human intervention to complete the test and measurement process.


Common Pairings: The GPIB communication protocol is commonly used with a variety of test and measurement instrumentation, such as voltmeters, ammeters, thermometers, oscilloscopes, and so on. These instruments and devices can be connected and controlled through the GPIB interface to automate the test and measurement process.


Common Industries: The GPIB communication protocol is widely used in industrial manufacturing, electronic testing, scientific research and other fields. Since it allows different instruments and devices to communicate through a unified interface, it is a very useful tool to help engineers and scientists perform test and measurement tasks faster and more accurately.

Daily Electronics Knowledge Lesson 43- Surge Suppression Ics

  Surge Suppression Ics is a surge suppressor, also known as a surge protector, is an electronic device that is mainly used to protect electrical equipment from damage caused by electrical surges. Surge suppressors are usually paired with equipment that needs to be protected against power surges such as power conversion equipment, communication equipment, computers, networking equipment, industrial control equipment, instrumentation, and so on. Its main principle is to use a Varistor to absorb electrical surges and convert them into harmless heat. When a surge occurs, the surge suppressor is able to respond quickly to control the voltage within the range that the equipment can withstand, preventing the equipment from being damaged by the surge.

Advantages of surge suppressors include: the ability to absorb large amounts of transient energy, protecting electronic equipment from damage by power surges; fast response time, which allows for quick absorption of power surges and reduces the likelihood of damage to equipment; and a relatively economical price.


However, the disadvantages of surge suppressors are: as they work by converting surges into heat to consume energy, they can generate a large amount of heat and require a good heat dissipation design; in addition, if a varistor fails, it can cause permanent electrical damage.


A common pairing of surge suppressors is with a lightning grounding strip. The surge suppressor (SPD) is connected between the enclosure of the power-using equipment and the ground strip, and an air switch is usually installed at the power line connection to protect the circuit. In the communications industry, surge suppressors are also often used in conjunction with twisted pair cables and SPDs.


Surge suppressor is usually used in electric power, communications, computers and other fields, used to protect a variety of electronic equipment from damage caused by power surges. Surge suppressors are also widely used in industrial control, intelligent buildings, transport facilities and other fields.


Daily Electronics Knowledge Lesson 42- Mica and PTFE Capacitors

  Mica and PTFE capacitors are non-polarised capacitive dielectrics for electronic equipment, typically used in applications requiring high stability and reliability. They consist of two metal foils (usually stainless steel or tinned aluminium) and a layer of insulating material made of Mica and PTFE (polytetrafluoroethylene).


Principle of operation: When two metal foils are separated by a layer of Mica and PTFE, an electric field is formed between them. When a voltage is applied, free electrons move under the action of the electric field, filling the difference in ion concentration in the dielectric and forming an electric current. Over time, the ion concentration will stabilise, forming a stable capacitor.



1. Durability: these capacitors have excellent durability due to the excellent chemical resistance, high temperature resistance and electrical properties of Mica and PTFE.

2. High dielectric constant: Due to the high dielectric constant of Mica and PTFE, they provide high capacitance and are suitable for use in applications requiring high energy storage.

3. Reliability: due to their consistent performance and excellent reliability, these capacitors are widely used in many demanding applications.




1. Higher cost: Mica and PTFE capacitors are usually more expensive than other types of capacitors and therefore may not be suitable in some low cost applications.

2. Large size: Due to the physical properties of Mica and PTFE, these capacitors are typically larger than other types of capacitors.


Common Pairings: Mica and PTFE capacitors are commonly used with power filters, power converters, high frequency signal processing, and other applications that require high stability and high reliability.


Common Industries: Mica and PTFE capacitors are widely used in automotive, aerospace, military, industrial equipment, telecommunication, data storage devices and power conversion.


In summary, Mica and PTFE capacitors are high-performance non-polarised capacitive dielectrics with excellent durability, high energy storage capacity and stability for use in applications requiring high reliability and stability. However, they may not be suitable for all application scenarios due to factors such as cost and large size.