Generally electrical switchgear rated upto 1KV is termed as low voltage switchgear. The term LV Switchgear includes low voltage circuit breakers, switches, off load electrical isolators, HRC fuses, earth leakage circuit breaker, miniature circuit breakers (MCB) and molded case circuit breakers (MCCB) etc i.e. all the accessories required to protect the LV system. The most… Continue reading Low Voltage Switchgear
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Protection of Lines or Feeder
As the length of electrical power transmission line is generally long enough and it runs through open atmosphere, the probability of occurring fault in electrical power transmission line is much higher than that of electrical power transformers and alternators. That is why a transmission line requires much more protective schemes than a transformer and an… Continue reading Protection of Lines or Feeder
Overvoltage Protection
There are always a chance of suffering an electrical power system from abnormal over voltages. These abnormal over voltages may be caused due to various reason such as, sudden interruption of heavy load, lightening impulses, switching impulses etc. These over voltage stresses may damage insulation of various equipments and insulators of the power system. Although,… Continue reading Overvoltage Protection
Motor Protection Circuit Breaker or MPCB
Motor protection circuit breakers are a specialized type of electrical protection device that is designed specifically for electric motors, like their name implies. Electric motors have plenty of applications and are used to drive mechanical devices of all types, so it is very important to protect them adequately with MPCBs. The following are just a… Continue reading Motor Protection Circuit Breaker or MPCB
Excitation Protection of Alternator
Loss of field or excitation can be caused in the generator due to excitation failure. In larger sized generator, energy for excitation is often taken from a separate auxiliary source or from a separately driven DC generator. The failure of auxiliary supply or failure of driving motor can also cause the loss of excitation in… Continue reading Excitation Protection of Alternator
Stator Earth Fault Protection of Alternator
This is to be noted that, the star point or neutral point of stator winding of an alternator is grounded through an impedance to limit the ground fault current. Reduced ground fault current causes less damage to the stator core and winding during ground or earth fault. If the ground impedance is made quite high,… Continue reading Stator Earth Fault Protection of Alternator
Fault of Electric Cable
It can be of three (3) types of electric cable faults found. They are There may be a short circuit between two conductors, There may be earth fault, i.e., fault between conductor and ground, There may be open circuit caused due to disconnection of the conductor. There can be more than one of the faults… Continue reading Fault of Electric Cable
Electric Poles
For carrying of overhead line, wooden poles, concrete poles, steel poles and rail poles are used. Which poles are to be used, depending on the importance of load, location, and place, cost effect of such construction, including maintenance cost, and keeping its profit element in mind. In low voltage line for all phases, natural and… Continue reading Electric Poles
Load Factor
What is Load Factor? In electrical engineering, the Load Factor is defined as a ratio of the average load divided by the maximum (or peak) load in a given time of period. In other words, the Load Factor is the ratio of total energy (kWh) used over a specific period of time to the total… Continue reading Load Factor
Impedance Matching
What is Impedance Matching? Impedance matching is defined as the process of designing the input impedance and output impedance of an electrical load to minimize the signal reflection or maximize the power transfer of the load. An electrical circuit consists of power sources like amplifier or generator and electrical load like a light bulb or… Continue reading Impedance Matching