Network Terminology: Defenitions associated to a network.

Introduction

In practice, the electrical circuits may consists of one or more sources (Voltage or Current) of energy, and number of electrical parameters (EX: Resistors, Inductors, Capacitors), that are connected in different ways (Series, Parallel, Series-Parallel). The combination of various sources of energy and elements forms a complicated electrical circuit i.e; generally referred as Networks. The term circuit and network are used synonymously in the electrical terminology. And the circuit analysis means to find the response (Current through or voltage across) any branch of the circuit.  

Here we shall define some of the basic elements which are commonly associated with a network.

NETWORK: Any arrangement of the various electrical energy sources along with the different circuit elements is called an Electrical network.

NETWORK ELEMENT: Any individual circuit element with two terminals which can be connected to other circuit element is called a network element.

        Network Elements can be either

a)      Active Elements

b)     Passive Elements

a)      Active Elements are the elements which supply Power or Energy to the Network.

     EX: Voltage Source and Current Source

b)     Passive Elements are the elements which either store energy or dissipate energy in the form of heat.

     EX: Resistor, Inductor and Capacitor

        Resistor is the element which dissipates energy in the form of heat.

        Inductor and Capacitor are the elements which stores energy.

BRANCH: A part of the network which connects the various points of the network with one another is called a Branch. A branch may consist of more than one element. In figure, AB, BC, AD, BD and CD are the branches.

JUNCTION POINT: A point where three or more branches meet is called a Junction Point. From Figure, B becomes junction point.

NODE: Nodes are classified into two types.

a                                a)  Principle Node   

                                                          b)   Simple Node

c                                                       c)   Reference Node

Principle Node is the point at which three or more elements are joined together is called as Principle Node. From figure B is the reference node.

Simple Node is the point at which two or more elements are joined together is called as Simple Node. Nodes A and C are the simple nodes.

Reference Node From the circuit shown D becomes the reference Node or Datum Node.

The Junction points are also the nodes of the network.

MESH or LOOP: Mesh and Loop are one and the same but there is a slight difference between Mesh and Loop.

Mesh is a set of branches forming a closed path in a network in such a way that if one branch is removed then remaining branches do not form a closed path.

A loop can be defined as a closed path which originates from a particular node , terminating at the same node, travelling through various other nodes, without travelling through any node twice. From figure, ABDA and BCDB are the two loops of the network.

                            

                                                             Fig: An Electrical Network