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

Medium Voltage Switchgear DefinitionMedium voltage switchgear ranges from 3 KV to 36 KV and is used to manage and protect electrical systems.Types of MV SwitchgearIncludes metal enclosed indoor and outdoor switchgear, and outdoor switchgear without metal enclosures.Short Circuit Current InterruptionThe main focus of circuit breaker design is to that all circuit breakers should be capable of interrupting short circuit current with a high degree of reliability and safety. The number of faulty trip

What is Electrical Switchgear Protection?Switchgear DefinitionA switchgear is defined as all the switching devices used in power system protection. It includes devices for control, metering, and regulating electrical power systems. When assembled logically, these devices form switchgear. In simpler terms, switchgear refers to systems that switch, control, and protect electrical power circuits and equipment.Switchgear and ProtectionWe all know about low voltage switches and re-wirable fuses at ho

What is High Voltage Switchgear?High Voltage Switchgear DefinitionHigh voltage switchgear is defined as equipment that manages voltages above 36KV to ensure safe and efficient power distribution.Main ComponentsHigh voltage circuit breakers, such as air blast, oil, SF6, and vacuum circuit breakers, are essential for interrupting high voltage currents.Essential Features of High Voltage Circuit BreakerThe essential features to be provided in high voltage circuit breaker, to ensure safe and reliable

What is Low Voltage Switchgear?Low Voltage Switchgear DefinitionLow voltage switchgear is defined as electrical switchgear rated up to 1kV, including protective devices like circuit breakers and fuses.Components of LV SwitchgearLV switchgear includes devices such as circuit breakers, isolators, and earth leakage circuit breakers to protect the system.Incomer FunctionThe incomer feeds incoming electrical power to the incomer bus. The switchgear used in the incomer should have a main switching dev

Earthing DefinitionEarthing of electrical transmission towers is defined as a safety measure where each tower is grounded to prevent electrical hazards.Footing ResistanceMeasuring the footing resistance ensures it is below 10 ohms, crucial for tower safety.Pipe EarthingIn the pipe earthing system, we use a galvanized steel pipe that is 25 mm in diameter and 3 meters long. The pipe is buried vertically in the soil, with its top 1 meter below ground level. If the tower stands on rock, the earthing

What is the Resistance of Earth?Earth Resistance DefinitionAn earth electrode is a metal rod or plate that is buried in the soil and connected to the earth terminal of an electrical system. It provides a low-resistance path for fault currents and lightning surges to dissipate into the ground. It also helps to stabilize the voltage of the system and reduce electromagnetic interference.Earth electrodes can be made from materials like copper, steel, or galvanized iron, chosen for their conductivity

What is a Shunt Reactor?Shunt Reactor DefinitionA shunt reactor is defined as an electrical device used in high voltage power systems to stabilize voltage during load changes.Voltage StabilizationIt controls dynamic overvoltage and provides capacitive reactive power compensation in systems above 400kV.Impedance TypesShunt reactors come in gapped core or magnetically shielded air core types to maintain constant impedance and avoid harmonic currents.Loss Measurement MethodsLosses of a shunt reacto

What is a Phase Synchronizing Device?Phase Synchronizing Device DefinitionA Phase Synchronizing Device (PSD) is defined as a device that synchronizes the switching of circuit breaker poles to the zero crossing of the phase voltage or current waveform.Controlled Switching DeviceAlso known as a Controlled Switching Device (CSD), it ensures accurate timing during circuit breaker operations.Voltage and Current SynchronizationThe PSD uses voltage and current waveforms to identify zero crossings and s

Arc Suppression Coil DefinitionAn arc suppression coil, also known as a Petersen coil, is an inductive coil used to neutralize the capacitive charging current in underground power networks during an earth fault.Purpose and FunctionThe coil reduces the large capacitive charging current during an earth fault by creating an opposite inductive current.Working PrincipleThe inductive current generated by the coil cancels out the capacitive current, preventing arcing at the fault point.Capacitive Curre

Shunt Reactor DefinitionA shunt reactor is defined as an electrical device that absorbs reactive power in power systems.Reactance CalculationThe reactance of a shunt reactor can be calculated as it is nearly equal to its impedance.V-I CharacteristicsThe simple formula of impedance in ohm isWhere, V is voltage in volt and I is current in ampere.But in the case of shunt reactor, impedance Z = reactance X.Where, V is applied voltage across the winding of the reactor and I is the corresponding curre