Page 51 - Electrician - TT (Volume 1)
P. 51

ELECTRICIAN - CITS




           3  According to the cross-sectional area of conductor.
              2 and 3 are find using micrometer
           Terms used in electrical cables
           Wire
           A solid conductor or an insulated conductor (solid or stranded) subjected to tensile strength with or without screen
           is called a wire.
           CABLE
           A  length  of  insulated  conductor  (single  or  stranded)  or  two  or  more  conductors,  each  provided  with  its  own
           insulation, which are laid up together
           TYPES
           1  Armoured cable: Provided with a wrapping of metal, serving as a mechanical protection.Used for underground
              system
           2  Flexible cable: Contain one or more cores, each formed of a group of wires. The diameter of wires sufficiently
              small afford flexibility
           Types of cables
           1  VIR (Vulcanized Indian Rubber) cable4.PVC (Poly Vinyl Chloride) cable
           2  TRS (Tough Rubber Sheathed) or5.Weather proof cable
              CTS (Cab Tire Sheathed) cable6. Flexible cable
           3  Lead sheath cable


            Wire joints - Types - Soldering methods


           Objectives: At the end of this exercise you shall be able to
           •   state the different types of wire joints and their uses
           •  state the necessity of soldering and types of soldering
           •  state the purpose and types of fluxes
           •  explain the different method of soldering and techniques of soldering
           •  explain the type of solder and flux used for soldering aluminium conductor.


           Definition of joint:  A joint in an electrical conductor means connecting/tying or interlaying together of two or
           more conductors such that the  union/junction becomes secured both electrically and mechanically.
           Types of joints: In electrical work, different types of joints are used, based on the requirement. The service to be
           performed by a joint determines the type to be used.

           Some of the commonly used joints are listed below.
           •  Pig-tail or rat-tail
           •  twisted joints
           •  Married joint

           •  Tee joint
           •  Britannia straight joint
           •  Britannia tee joint
           •  Western union joint
           •  Scarfed joint

           •  Tap joint in single stranded conductor


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