Page 49 - Electrician - TT (Volume 1)
P. 49

ELECTRICIAN - CITS





             Fig 23















           Open circuit: An open in the common line of a point A shown in figure. Then cause no current flow in the circuit
           where as an open in the branch at point B causes no current flows only in that branch. (Fig 24)
             Fig 24
















           Conductors and cable

           Classification of conductors
           Bare conductor: Which are not covered with insulation. The most use of bare conductors is in overhead lines
           and earth conductor. forearthing also bare conductors are used. (Fig 25)

            Fig 25





           Insulated conductor: Which are covered with insulation.the insulation separates the conductor electrically from
           other conductors and from the groundings. It allows conductors to be grouped without danger. Used for indoor
           wiring and underground distribution system (Fig 26)

            Fig 26











           Solid conductor

           There will be only one conductor in the core. Used for bus bars and winding of machines.
           Stranded conductor: There will be a number of smaller sized conductor’s twister to form the conductor. Used in
           cables and overhead lines
           Common conductors and properties: In electrical work, mostly copper and aluminum are used for conductors.
           Though silver is a better conductor than copper, it is not used for general work due to higher cost.


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                                    CITS : Power - Electrician & Wireman - Lesson 5 - 12
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