electrical mess

SPLIT PHASE INDUCTION MOTOR   In this type there will be two windings. main winding auxiliary winding or starting winding The circuit diagram is show in below fig which consist of main winding and auxiliary winding, where the starting winding has more resistive in nature and the main winding has more inductive in nature.  This is because to start this motor the currents of main winding(I m ) and starting winding (I s ) should maintain a phase angle less than 90 o and both windings produces Φ m and Φ s fluxes .By this rotating magnetic field is produced and induction motor will starts rotating in one direction.The direction of rotor can be changed by changing the terminal of main winding or starting winding.This makes change in the direction of rotating magnetic field and rotor rotates in opposite direction. Due to high inductive nature of main winding its current I m lags voltage V by an angle less than 90 o and highly resistive nature of starting wi...

Transformer construction Basic construction details of transformer :- The main parts of transformer are 1)core or magnetic core 2)winding 3)Transformer tank 4)transformer oil 5)Conservative tank 6)Breather 7)Buecholz Rely 8)oil gauge 9)Terminal Bushing 10)Exposition Vent 11)Radiators 1)Magnetic core:- Generally transformer consists of soft iron or silicon steel core.The mainfunction of core is produce a path of low relactance between two winding of the transformer . Magnetic core made up of Silicon steel with thin lamination . The lamination thickness is 0.35 mm to 0.5mm depending up on the requirements and size and shapes of the transformer. Core is cuts the alternating flux due to this cuting action induce the emf.Due to this emf current create in core that current circulate the magnetic core is called eddy current .This eddy current cu loss or I 2 R loss form in the transformer .Due this loss magnetic strength of the transformer is decreased . we c...

Rotating field power factor meter A 1 ,A 2 ,A 3 are three fixed coils which are displaced 120 o from each other These coils are connected to a 3-Φ R,Y and B power supply through current transformers as shown in figure. Coil(P) is a fixed coil connected in series with a high resistance across on pair of 3-Φ lines and iron cylinder(c) is mouted inside coil(P). To the iron cylinder(c) two sector shaped vanes(v) are provided which are 180 o apart in space. The damping vanes and apointer is mounted on spindle and there is no controlling system in this powerfactor meter. Coils A 1 ,A 2 and A 3 produce a rotating magnetic field.These field interacts with the coil(p) and iron system's alternating field. This causes an angular displacement in moving system which is determined by the phase angle of the current.    Vanes v are magnetized by currnet I p in coil(p) which is in phase with and proportional to the line voltage of the system.let hysteresis and eddy cu...

TRANSFORMER Introduction: The main advantage of A.C. over D.C. is that the A.C. can be transferable from low voltage to high voltage and high voltage to low voltage.Alternating voltages can be raised or lowered as per requriments in the different stages of electrical network as generration,transmission, distribution and utilization.This is possible with a static device called transformer. The transformer works on the principle of mutual induction.It transfers an electric energy from one circuit to other when there is no electrical connection between the two circuits. def: The transformer is a static device which transforms electrical energy from alternating circuit to another alternating circuit with desired change in voltage and current ,but not the change in frequency.