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

Over - voltage and Over - current Aspects Ferroresonant over - voltage: In a non - effectively earthed neutral system, the magnetic circuits of equipment such as transformers, voltage transformers, and arc suppression coils may saturate, potentially triggering ferroresonance. The resulting over - voltage can increase the excitation current of the voltage transformer by dozens of times. Operating under high voltage and large current for an extended period causes the temperature of the transformer

Definition of Electromagnetic Flow MeterAn electromagnetic flow meter is a device used to measure the flow of liquid as it passes through a pipeline. More specifically, electromagnetic flow meters are used to measure the flow rate of electrically conducting fluids. An electrically conductive liquid refers to any liquid that allows an electric current to pass through it.Working Principle of Electromagnetic Flow MeterElectromagnetic flow meters operate based on Faraday's Law of electromagnetic ind

Principles of the Half-Deflection MethodThe Half-Deflection Method is a technique used to measure the internal resistance of a galvanometer. This method is adopted primarily because it is relatively simple and does not require additional precision instruments or complex circuit setups. Below are the reasons for using the half-deflection method along with its underlying principles:Basic Principles of the Half-Deflection MethodInitial State: First, connect the galvanometer to a known voltage sourc

Applications of Current Transformers in Industrial SettingsCurrent Transformers (CTs) play a crucial role in industrial applications, primarily used for measuring and protecting power systems that handle large currents. Below are the main uses of current transformers:1. MeasurementHigh-Precision Monitoring: CTs can proportionally convert large primary currents to smaller secondary currents, allowing standard measurement instruments (such as ammeters and wattmeters) to safely and accurately measu

How Partial Discharge Testing Enhances the Reliability of High-Voltage Equipment and Its LimitationsPartial discharge testing (PD Test) is a crucial method for assessing the insulation performance of high-voltage equipment. By detecting and analyzing partial discharge phenomena, potential insulation defects can be identified, thereby enhancing the reliability of high-voltage equipment. Below are the specific mechanisms through which partial discharge testing improves reliability and its limitati

Methods to Determine Coil TemperatureThere are several methods to determine coil temperature, and the choice depends on the application scenario, required accuracy, and available equipment and technology. Below are some commonly used methods to determine coil temperature:1. Direct Measurement Methodsa. Thermocouples Principle: Thermocouples utilize the thermoelectric effect produced by the contact of two different metal materials to measure temperature. Usage: Install the thermocouple probe near

How Engineers Test the Fatigue Resistance of WiresTesting the fatigue resistance of wires is a crucial step to ensure their reliability and safety during long-term use. Wires are subjected to repeated bending, stretching, and vibration in practical applications, so evaluating their fatigue performance is essential. Below are some methods and techniques that engineers typically use to test the fatigue resistance of wires.1. Bending Fatigue TestPurpose:To assess the durability of wires under repea

Electrical fault testing is a critical component of power system maintenance and management, aimed at detecting and preventing potential faults early to ensure the stability and reliability of the electrical grid. By identifying and addressing issues before they escalate, electrical fault testing helps prevent large-scale power outages. Below are the key measures and strategies involved in this process:1. Regular Preventive Maintenance and Testing Preventive Maintenance: Regularly inspect and ma

Why is the Open Circuit Test Performed at Rated Voltage?The open circuit test (Open Circuit Test, OCT), also known as the no-load test, is typically conducted by applying the rated voltage to the low-voltage side of a transformer. The primary purpose of this test is to measure the transformer's performance parameters under no-load conditions, such as excitation current, no-load losses, and the voltage ratio at no load. Below are the reasons why the test is performed at rated voltage:1. Reflectin

What is a Contact Resistance Meter?A contact resistance meter is a specialized instrument designed to measure the contact resistance between electrical connection points, such as terminals, plugs, sockets, switch contacts, and relay contacts. Contact resistance refers to the resistance formed at the interface where two conductive surfaces meet. While typically much smaller than the resistance of the conductors themselves, excessive contact resistance can lead to poor current flow, overheating, a