Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

The working principle of surge protection devicesSurge Protective Devices (SPDs) are important safety devices primarily designed to protect electrical and electronic equipment from the effects of voltage spikes and surges. Here's how they work:1. Surge protectors in normal working conditionIn normal working conditions, surge protectors present high impedance to normal power frequency voltages, with almost no current flowing through them, equivalent to an open circuit. This means that surge prote

Modern dielectric oil breakdown voltage testers are instruments used to measure the breakdown voltage of insulating oils, such as transformer oil and switchgear oil. These instruments are crucial in power systems, electrical equipment manufacturing, and maintenance to ensure the quality of insulating oils and the safe operation of electrical equipment. Here are the main features of modern dielectric oil breakdown voltage testers:Main FeaturesHigh Precision Measurement:Modern dielectric oil break

A vector voltmeter is an instrument used to measure and analyze alternating current (AC) signals. It provides information about both the magnitude and phase of the signal. Unlike traditional voltmeters, which only measure the amplitude (or magnitude) of the voltage, a vector voltmeter can also measure the phase angle, offering a more comprehensive description of the signal's characteristics. Here are some key features and applications of a vector voltmeter:Key FeaturesAmplitude Measurement:A vec

Whether DC grounding points and AC grounding points can be shared depends on the specific system design, safety standards, and regulations. Here are some key points to help you understand this issue:1. Safety Standards and RegulationsNational Standards: Different countries and regions have different electrical safety standards and regulations. For example, China's national standard GB/T 16895 and the United States' National Electrical Code (NEC) provide detailed guidelines for grounding in both

Using a carbon dioxide (CO₂) fire extinguisher on a high-voltage transformer is generally safe, but there are important considerations to keep in mind. Here are the key points regarding the safety and precautions:SafetyNon-Conductive: Carbon dioxide (CO₂) is an inert gas and does not conduct electricity. Therefore, using a CO₂ fire extinguisher to extinguish electrical fires does not increase the risk of electric shock, which is one of its main advantages.No Residue: CO₂ leaves no residue after

Using miniature circuit breakers (MCBs) instead of fuses for electrical distribution has many advantages, but it also comes with some potential disadvantages. Here are the main potential drawbacks:1. CostInitial Cost: The initial cost of MCBs is typically higher than that of fuses. MCBs contain more mechanical and electronic components, making them more expensive to manufacture.Maintenance Cost: While MCBs have a longer lifespan and can be reused, they may require repair or replacement if they f

A switching power supply's output voltage being too high can be caused by several factors. Here are some common reasons and their explanations:1. Feedback Loop FaultsFaulty Feedback Resistor or Capacitor: Damage to the resistors or capacitors in the feedback loop can cause the feedback signal to be inaccurate, leading to an increase in output voltage.Optocoupler Failure: Optocouplers are commonly used in switching power supplies to transmit feedback signals. If the optocoupler is damaged or aged

Cable voltage leakage (also known as insulation failure or leakage current) is a serious electrical issue that can not only damage equipment but also cause fires and personal injuries. Handling cable voltage leakage requires a series of measures, from detection to repair, to ensure the safety and reliable operation of the electrical system. Here are the steps and methods for handling cable voltage leakage:1. Power Off and Safety MeasuresPower Off: First, ensure that the power is disconnected to

A relay protection tester is a specialized instrument used for testing and calibrating relay protection devices. It plays a crucial role in power systems, ensuring the reliability and accuracy of relay protection devices. Here are the main features of a relay protection tester:1. MultifunctionalityComprehensive Testing: Relay protection testers can perform a wide range of tests, including current, voltage, frequency, phase angle, impedance, differential protection, and more.Various Protection Ty

The current-carrying capacity of a 0.75 mm² copper wire depends on several factors, including the operating environment, type of insulation, whether the wire is installed in conduit, and the number of wires. Here are some common scenarios and their corresponding current ratings:1. Household PVC-Insulated Copper WireAccording to general experience and standards, the safe current-carrying capacity of household PVC-insulated copper wire is as follows:Safe Current Rating: 6 A per square millimeter.S