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

What is Metal Enclosed Switchgear?Definition of Metal Enclosed SwitchgearMetal enclosed switchgear is a type of electrical equipment with a fully enclosed metal casing containing various electrical components for medium-voltage applications.Purpose and FunctionIt is designed to provide protection, control, and isolation for electrical circuits and equipment.Categories of SwitchgearMetal Enclosed Indoor SwitchgearMetal-enclosed indoor switchgear is designed for indoor installation in buildings or

What is an ELCB?ELCB DefinitionAn Earth-leakage circuit breaker (ELCB) is a safety device used in electrical installations (both residential and commercial) with high Earth impedance to prevent electric shocks. It detects small stray voltages on the metal enclosures of electrical equipment, and interrupts the circuit if a dangerous voltage is detected.ELCBs help detect current leaks and insulation failures in the electrical circuits that would cause electrical shocks to anyone coming into contac

What is Miniature Circuit Breaker?MCB DefinitionAn MCB is defined as an automatically operated switch that protects low voltage electrical circuits from excess current due to overload or short circuit.Fuse vs MCBNowadays miniature circuit breakers (MCBs) are much more commonly used in low voltage electrical networks instead of fuses. The MCB has many advantages compared to a fuse: It automatically switches off the electrical circuit during the abnormal conditions of the network (both overload an

How to Calculate Short Circuit Current?Short Circuit Current DefinitionShort circuit current is defined as the large current that flows through an electrical system when a fault occurs, causing potential damage to circuit breaker components.When a short circuit fault happens, a large current flows through the system, including the circuit breaker (CB). This flow, unless stopped by the CB tripping, subjects the CB parts to significant mechanical and thermal stresses.If the CB’s conducting parts l

Circuit Breaker DefinitionA circuit breaker is defined as a device that opens and closes electrical contacts to protect circuits from faults.Therefore, circuit breakers must operate reliably without any delay. To ensure this reliability, the operating mechanism is more complex than it first appears. The distance and speed of the moving contacts during opening and closing are crucial design parameters for circuit breakers.Contact gap, traveling distance of moving contacts and their velocity are d

Definition of Routine TestsRoutine tests are regular evaluations conducted to ensure the quality and performance of circuit breakers.Power Frequency Over Voltage TestThis test checks if circuit breakers can handle unexpected high voltage conditions.Dielectric TestPower system can experience temporary overvoltage conditions due to various reasons, like sudden load changes or incorrect tap changer operations. The power frequency over voltage withstand test checks if a circuit breaker’s insulation

Circuit Breaker DefinitionA circuit breaker is defined as a device designed to protect an electrical circuit from damage caused by overcurrent or short circuits by interrupting the flow of electricity.Short Circuit Breaking Current of Circuit BreakerThis is the maximum short circuit current which a circuit breaker (CB) can withstand before it, finally cleared by opening its contacts.When a short circuit flows through a circuit breaker, it causes thermal and mechanical stresses in the breaker’s c

What is High Voltage Testing?High Voltage Testing DefinitionHigh voltage testing involves procedures to ensure that electrical equipment can withstand various voltage stresses during its operational lifespan.Transformer Testing MethodsEssential to evaluate the integrity of electrical systems, including tests for dielectric strength, capacitance, and breakdown voltage.Test TypesThere are mainly four types of high voltage testing methods applied on high voltage equipment and these areSustained low

What is Circuit Breaker Maintenance?Circuit Breaker Maintenance DefinitionCircuit breaker maintenance involves switching off, isolating, and regularly checking and servicing the breaker to ensure reliable operation.Bulk Oil Circuit BreakerFor bulk oil circuit breaker, we should check contact burning. If burning is very light, remove the burn beads and polish the surface. If burning is quite heavy, replace the tips and arcing ring by new set. We should loose and tight the tips few times before fi

What is SF6 Gas?SF6 Gas DefinitionSF6 gas is defined as a compound of one sulfur atom and six fluorine atoms, known for its stability and use in electrical systems.Manufacturing ProcessSF6 gas is commercially manufactured by the reaction of fluorine (obtained by electrolysis) with sulfur.During process of producing of this gas, other byproducts like SF4, SF2, S2F2, S2F10 are also produced in small percentages. Not only these byproduct, impurities like air, moisture, and CO2 are also present in t