The main advantage of Moving Iron Instrument is that it can measure AC as well as DC quantities. Though this instrument is responsive to DC, it suffers from hysteresis error which causes an appreciable error in the measurement of DC. Therefore, it is rarely used...
Continue reading »
August 1, 2018 admin
Measurement and Instrumentation
No Comment
What is Rogowski Coil? Rogowski Coil is an electrical device used for the measurement of alternating (AC) current. It can measure high speed transient current, pulsed current as well as power frequency AC current. It is simply a toroidal coil named after German physicist Walter...
Continue reading »
July 23, 2018 admin
Measurement and Instrumentation
No Comment
Synchronous Machine is electromechanical equipment in which the speed of rotating part i.e., Rotor, is equal to the speed of rotation of magnetic flux. The speed of rotation of magnetic flux is called synchronous speed. That is why these types of equipment is called synchronous...
Continue reading »
July 16, 2018 admin
Electrical Machines
No Comment
Definition Short Circuit Ratio, or SCR, is the ratio of field current required to generate rated voltage under open circuit condition, to the field current required to circulate the rated armature current under three phase short circuit condition. It is an important quantity of synchronous...
Continue reading »
July 13, 2018 admin
Electrical Machines
No Comment
Zero Power Factor Characteristics Zero Power Factor Characteristics (zpfc) of synchronous generator is a plot between the armature terminal voltage and field current for a constant value of armature current and speed. A purely inductive load is connected across the generator terminal to achieve zero...
Continue reading »
July 12, 2018 admin
Electrical Machines
No Comment
The main purpose of compensating winding is to nullify the effect of armature reaction on the main field flux under the pole faces in DC machine. Due to the effect of armature reaction mmf, the flux distribution under the pole faces is distorted which leads...
Continue reading »
July 11, 2018 admin
Electrical Machines
No Comment
DC motor is an electromagnetic device which converts electrical energy into mechanical energy. DC power input is converted into mechanical power at the shaft motor. This article describes the construction of DC motor. There is no difference in the construction of DC Motor and Generator....
Continue reading »
July 5, 2018 admin
Electrical Machines
No Comment
Thevenin’s Theorem is the most used and useful approach to solve electrical networks. This is not a new way or approach rather it’s the same conventional way what we use to solve electrical networks but in an organized manner. Let me explain why this is...
Continue reading »
July 3, 2018 admin
AC Circuit
No Comment
1 Unit Electricity is the amount of electrical energy consumed by a load of 1 kW power rating in 1 hour. It is basically measurement unit of electrical energy consumption in Joule. 1 kWh (kilo watt hour) and 1 Unit are same. 1 kWh is...
Continue reading »
June 23, 2018 admin
AC Circuit
2 Comments
The major difference between Instantaneous and Definite Time Overcurrent Relay lies in their operating time. The former operates instantaneously while the latter one operates after a definite time. Both Instantaneous and Definite Time Overcurrent Relay senses an over current in the circuit and gives tripping...
Continue reading »
June 22, 2018 admin
Power System Protection
3 Comments
