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working principle of a current transformer (CT)

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 The working principle of a current transformer (CT) is based on Faraday's law of electromagnetic induction. A current transformer is a type of instrument transformer that is used to measure high currents in power systems and convert them into manageable levels for measurement or protection purposes. Here's a brief explanation of the working principle of a current transformer: Construction: A current transformer consists of a primary winding, a secondary winding, and a magnetic core. The primary winding is connected in series with the high-current line carrying the load, while the secondary winding is connected to the measuring or protection devices. Magnetic Induction: When a current flows through the primary winding, it creates a magnetic field around the conductor according to Ampere's circuital law. The magnetic core, usually made of laminated iron or ferrite material, is placed around the primary winding. The core helps in concentrating and guiding the magnetic field...
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Number of parallel paths in DC machine

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  lap winding : This is the lap winding diagram of DC machine. It is for 4 pole and 20 slot armature. As we know no. of commutator segments=no. of armature coils(C). So from the above diagram we can easily find that five coils(C/P) are located under one pole-pair(NS) and are series connected so that their emfs add up.This constitute one parallel path. So the complete armature winding can be divided into such four paths(equal to the no. of poles) lying under the four poles. So it can be concluded that no. of parallel path in lap-wound machine is equal to no. of poles. wave winding: In wave winding the "finish" end of one coil under "one pole pair" is connected to "start" of a coil under the "next pole pair". The process is continued till all the armature coils are connected and winding becomes a closed one.Wave name is only due to appearance. In wave winding the coils are divided into two groups-All the coils with clockwise current are series conn...
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