Measurement of Resistance using Potentiometer
05/16/2025
A double-pole double-throw (DPDT) switch is incorporated into the circuit. When the switch is moved to position 1, the unknown resistance is connected to the circuit; when shifted to position 2, the standard resistance is connected instead.
Topics
The Electricity Encyclopedia is dedicated to accelerating the dissemination and application of electricity knowledge and adding impetus to the development and innovation of the electricity industry.
What is the difference between a dielectric and an insulator?
Dielectrics and insulators are distinguished primarily by their applications. One of the main differences is that a dielectric can store electrical energy by becoming polarized in an electric field, whereas an insulator resists the flow of electrons to prevent current conduction. Other key differences between them are outlined in the comparison chart below.Definition of DielectricA dielectric material is a type of insulator that contains few or no free electrons. When subjected to an electric fi
08/30/2025
Transformer Connection Sections
Transformer Connection DesignationsThe transformer connection designation indicates the winding connection method and the phase relationship between the line voltages of the primary and secondary windings. It consists of two parts: letters and a number. The letters on the left denote the connection configurations of the high-voltage and low-voltage windings, while the number on the right is an integer from 0 to 11.This number represents the phase shift of the low-voltage winding's line voltage r
08/15/2025
Automatic Reclosing Scheme in Transmission Systems
Automatic Reclosing Scheme for Transmission SystemsThe automatic reclosing system is a series-connected network designed to reduce operating costs and enhance network reliability. Extra-high voltage (EHV) transmission lines are used to transmit large amounts of power, on the order of thousands of megawatts (MW), and therefore should not be interrupted at all costs. Although faults on these overhead lines are common, the power transmitted through them should not be interrupted for long periods du
08/07/2025
Transformer operation and maintenance
Transformer Operating TemperatureDuring operation, transformers generate copper losses and iron losses, both of which are converted into heat, causing the transformer’s temperature to rise. Most transformers in China use Class A insulation. Due to heat transfer characteristics, significant temperature differences exist between different components during operation: winding temperature is the highest, followed by the core, and then the temperature of the insulating oil (with upper-layer oil being
07/31/2025
