Electrical Designing

Phase is the differnce between waves, through which the current flows. 1 phase consists of 3 wires , 1 phase 1 neutral and 1 stay wire. 3 phase consists of 5 wires , 3 phases(R, Y, B), 1 neutral and 1 stay wire. In most of the transformers 3 phases are mostly used except the road side transformers because the voltage of 3 phase is 440v. In domestic appliances 1 phase is used because the voltage required is 230v 1. Single phase voltage is compare then three phase voltage is very low for ex- 1 phase 240v < 3 phase 440v. 2. Three phase can make rotating magnatic field but single phase can not make rotating magnatic field. 3. In three phase is phase sequence but single phase is not phase sequence.

Electrical Circuit : An electrical circuit is a closed conducting path through which electric current either flows or is intended to flow. Electrical Network : An electrical network is an interconnection of electrical elements such as resistors, inductors, capacitors, transmission lines, voltage sources, current sources, and switches. It may not be a closed path.Thats why an electrical circuit is a network but not vice versa. Bilateral Circuit : A circuit whose properties remains same in either directions is called bilateral circuit. Loop : A closed electric circuit is called a loop. It may or may not contain any closed path in it. Mesh : A mesh is a set of branches that forms a closed path in a network and which contains no closed path in it. A mesh can be called as a loop but not vice versa.

What is Direct Current ? Direct Current : Electric current which flows in one direction only through a circuit or equipment. The associated direct voltages, in contrast to alternating voltages, are of unchanging polarity. Direct current corresponds to a drift or displacement of electric charge in one unvarying direction around the closed loop or loops of an electric circuit. Direct currents and voltages may be of constant magnitude or may vary with time. For more detailson this topic see the following site : http://www.kpsec.freeuk.com/acdc.htm

Current : The rate of flow of electrons through a circuit is defined as current . In general current is denoted with "I or i".The unit of current is coulombs/sec which is called as "amperes(A)". Voltage or Potential: Voltage is measure of the work required to move charge from one point to another in electric field. Its unit is Joules/Coloumb called as Volt (V). V=w/q. Potential difference : (i) the difference in electrical potential between two points in a circuit expressed in volts(V). (ii) the difference in electrical charge between two points in a circuit expressed in volts(V).