Page 49 - Electrician - TT (Volume 1)

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