# Circuit Theory

## Generation of Alternating Voltage

The voltage which changes polarity at regular interval of time is known as the alternating voltage. The one complete cycle of an alternating quantity consists two half cycles. And the direction of a half cycle changes after every particular interval of time. The machine which generates the alternating voltage is known as the alternator. The …

## Two Wattmeter Method – Balanced Load Condition

The Two Wattmeter Method is explained, taking an example of a balanced load. In this, we have to prove that the power measured by the two wattmeter i.e. the sum of the two wattmeter readings is equal to root 3 times of the phase voltage and line voltage (√3VLIL Cosϕ) which is the actual power …

## Two Wattmeter Method of Power Measurement

Two Wattmeter Method can be employed to measure the power in a 3 phase, three-wire star or delta connected the balanced or unbalanced load. In two wattmeter method, the current coils of the wattmeter are connected with any two lines, say R and Y and the potential coil of each wattmeter is joined on the …

## Measurement of Three Phase Power: Three Wattmeter Method

Power measurement in an AC circuit is measured with the help of a Wattmeter. A wattmeter is an instrument which consists of two coils called Current coil and Potential coil. The current coil having low resistance is connected in series with the load so that it carries the load current. The potential coil having the …

## Star to Delta and Delta to Star Conversion

The conversion or transformation or replacement of the star connected load network to a Delta connected network and similarly, a delta connected network to a star network is done by Star to Delta or Delta to Star Conversion. Contents: Star to Delta Conversion Delta to Star Conversion Star to Delta Conversion In star to delta …

## Generation of 3 Phase Power in 3 Phase Circuits

Power in 3 Phase Circuits The three-phase power is mainly used for generation, transmission and distribution of electrical power because of their superiority. It is more economical as compared to single-phase power and requires three live conductors for power supply. Power in a single-phase system or circuit is given by the relation shown below: Where, …

## Circuit Analysis of 3 Phase System – Balanced Condition

The electrical system is of two types i.e., the single-phase system and the three-phase system. The single-phase system has only one phase wire and one return wire thus it is used for low power transmission. The three-phase system has three live wire and one returns the path. The three-phase system is used for transmitting a …

## Delta Connection In a 3 Phase System

In Delta (Δ) or Mesh connection, the finished terminal of one winding is connected to start terminal of the other phase and so on which gives a closed circuit. The three-line conductors are run from the three junctions of the mesh called Line Conductors. The connection in delta form is shown in the figure below: …

## Star Connection in a 3 Phase System

In the Star Connection, the similar ends (either start or finish) of the three windings are connected to a common point called star or neutral point. The three-line conductors run from the remaining three free terminals called line conductors. The wires are carried to the external circuit, giving three-phase, three-wire star connected systems. However, sometimes …

## Advantages of 3 Phase Over Single Phase System

The three-phase system has three live conductors which supply the 440V to the large consumers. While the single-phase system has one live conductor which is used for domestic purposes. The following are the main advantages of 3 Phase system over Single Phase system. Higher Rating The rating, i.e. the output of a three-phase machine is …