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

Analysis of Measurement Errors in Electrical Instruments and Elimination Strategies1.Electrical Instruments and Common Testing MethodsElectrical instruments play a vital role in the generation, transmission, and utilization of electricity. As a special form of energy, electricity requires strict safety standards in production and use. Safe electricity usage is crucial to daily life, production, and socio-economic development. Power system monitoring relies on electrical instruments, which are of

Multifunction Power MeterA multifunction power meter is an intelligent instrument equipped with a digital processor, featuring programmable measurement, display, digital communication, and energy pulse transmission. It can perform electrical measurement, energy metering, data display, collection, and transmission. Some models also offer additional functions such as fault alarms, harmonic analysis, data statistics, and time logging.Multifunction power meters are widely used in substation automati

How to Use a Power Meter1. Connecting the CircuitBefore using a power meter, connect it to the circuit under test. Pay attention to the following points during connection: Select an appropriate measurement range based on the characteristics of the circuit. If the voltage or current in the circuit exceeds the meter's range, it may result in significant errors or even prevent measurement. Ensure correct connection of the current and voltage input terminals to avoid wiring mistakes. For measuring A

I. Common Fault Types and Diagnostic MethodsElectrical Faults Circuit Breaker Failure to Operate or Maloperation: Check the energy storage mechanism, closing/tripping coils, auxiliary switches, and secondary circuits. High-Voltage Fuse Blown: Measure voltage across the fuse terminals; inspect busbar joints, cable terminations, and protection relay settings. Busbar Discharge or Insulator Damage: Listen for discharge sounds, check temperature at busbar connections, and visually inspect insulators

Types and Common Fault Analysis of High-Voltage SwitchgearHigh-voltage switchgear is a critical electrical device in power systems. Deterioration in switchgear operation is one of the main causes of power system failures. What are the common faults in high-voltage switchgear?(1) Outdoor and Indoor TypesBased on installation environment, high-voltage switchgear can be classified as outdoor or indoor types. Equipment rated at 10 kV and below is mostly installed indoors. According to primary circui

Oil-Immersed Transformers: Overview, Features, and ApplicationsAn oil-immersed transformer is a widely used type of power transformer that employs a liquid—typically insulating oil—as both an insulating and cooling medium.Key Features of Oil-Immersed Transformers: Insulating Oil: Insulating oil serves as the primary dielectric medium, electrically isolating the windings from the core and ground. With its high dielectric strength, it effectively prevents electrical breakdown between windings or b

The absorption ratio is defined as follows: When operating a megohmmeter (insulation resistance tester), rotate the handle at a speed of 120 revolutions per minute. Record the insulation resistance reading at 15 seconds (R15) and then at 60 seconds (R60). The absorption ratio is calculated using the formula:Absorption Ratio = R60 / R15, which should be greater than or equal to 1.3.Measuring the absorption ratio helps determine whether the insulation of electrical equipment is damp. When insulati

I. Operational Analysis1.1 Operating ScopeHigh-voltage disconnect switches are classified into outdoor and indoor types based on installation location, and into three-pole or single-pole configurations according to the number of poles. During operation, attention must be closely paid to the switch’s operating current and voltage.If the operating voltage exceeds the rated value, discharge may occur within the porcelain insulator. The degree of heating is closely related to the operating current a

During the operation of high-voltage disconnect switches, arcs may form between the contacts when they separate while current is still flowing. The high temperature of the arc not only damages the switch contacts but can also ignite surrounding flammable materials, leading to safety accidents.Arc formation is influenced by various factors, including the type of current (DC or AC), the inductive and capacitive characteristics of the circuit, and the properties of the contact materials. In DC syst

With the continuous advancement of mechanization in modern society, the demand for electrical energy in daily life has significantly increased. To ensure that power supply meets this growing demand, the power system must operate with greater stability, safety, and real-time responsiveness. This highlights the critical importance of high-voltage disconnector switch quality during manufacturing.Manufacturers must strengthen their awareness of this responsibility to ensure reliable operation of hig