Basics Of Electrical Wires & Cables - Residential & Commercial Projects

MEP

1. Basics Of Electrical Wires & Cables - Residential & Commercial Projects S.Sudha Velan B.E (Civil)

2. Electric wires Electric wires are typically made of aluminum or copper. They are either bare or insulated and typically covered in a thin layer of PVC . Electric Cables Cables contain at least a neutral wire, ground wire and hot wire that are twisted or bonded together. Depending on its purpose, the cable may contain more wires. The wires in a cable are insulated in their own color-coded layer of PVC. The group of wires is then encased in an outer sheath to make up the single cable. 

3. Copper ( vs ) Aluminium Copper is a better conductor of electricity and it will act better in case of conducting electricity, When measuring the conductivity it’s not just the resistivity but there are two more factors that we must consider which is the size of the cables and the insulation materials used. In case of super-high voltage carried for longer distance, Aluminium is much economical and better conductor as compared to Copper. Aluminium may have 61 percent of Copper’s conductivity but has only 30 percent weight as that of copper which makes them easier to spread across. Aluminium is also inexpensive as compared to Copper and hence used vividly in the making of electrical wires.

4. Stranded Wire A stranded wire is made of a quantity of thin (usually copper) strands that are twisted and bundled together and generally enclosed in a PVC material to form a multi-stranded conductor.  Stranded Wire Applications Stranded wires are mainly used for indoor applications. The  benefits of stranded over solid wire  is that stranded wire is made to bend and twist;

5. Types Of Stranded Wire Concentric Strand A concentric stranded conductor consists of a central wire or core surrounded by one or more layers of helically laid wires. Each layer after the first has six more wires than the preceding layer.

6. Bunch Strand The term bunch stranding is applied to a collection of strands twisted together in the same direction without regard to the geometric arrangement.

7. Rope Strand A rope stranded conductor is a concentric stranded conductor each of whose component strands is itself stranded. A rope stranded conductor is described by giving the number of groups laid together to form the rope and the number of wires in each group.

8. Annular Strand   An annular conductor is a round, stranded conductor whose strands are laid around a suitable core. The core is usually made wholly or mostly of non-conducting material. This construction has the advantage of lower total AC resistance for a given cross-sectional area of conducting material due to the skin effect.

9. Compact Strand A compact stranded conductor is a round or sector conductor having all layers stranded in the same direction and rolled to a predetermined ideal shape. The finished conductor is smooth on the surface and contains practically no interstices or air spaces. This results in a smaller diameter.

10. Compressed strand Compressed conductors are intermediate in size between standard concentric conductors and compact conductors . Un- compressed strand Compressed strand

11. Sector Strand A sector conductor is a stranded conductor whose cross-section is approximately the shape of a sector of a circle. A multiple conductor insulated cable with sector conductors has a smaller diameter than the corresponding cable with round conductors.

12. Segmental Strand  Segmental conductor is a round, stranded conductor composed of three or four sectors slightly insulated from one another. This construction has the advantage of lower AC resistance due to increased surface area and skin effect.

13. HEAT RESISTANT AND FLAME RETARDANT FLEXIBLE CABLES FLAME RETARDENT LOW SMOKE AND HALOGEN FLEXIBLE CABLES ( frls ) FLAME RETARDENT FLEXIBLE CABLES ( frl )

14. COAXIAL CABLES (RG6 SERIES) LAN CABLES ( CAT 6 SERIES) TELEPHONE CABLES

15. Single Conductor Wire Single Conductor wire is the most popular choice for electrical layout inside a home. It is available in multiple gauges, color and solid or stranded conductors. A single solid wire provides better connections but single stranded wires are easier to route through conduits

16. Non-Metallic Sheathed Wires:  The non-metallic wires are used for in-house wiring. It may consist of 2 or more than 2 insulated conductors with an insulated or bare ground conductor. There is another layer of plastic XLPE sheathing for more protection. XLPE - Cross Linked Polyethylene

17. PVC INSULATED POWER AND CONTROL CABLES XLPE INSULATED POWER AND CONTROL CABLES FLAT SUBMERSIBLE CABLES (MULTICORE) CCTV CABLES (3+1 & 4+1 CATEGORY) XLPE - Cross Linked Polyethylene

18. This type of electrical cable is designed to be used in wet locations or submersed in a liquid .

19. Types Of Cables AYY - Aluminium Conductor, PVC Insulated, PVC Outer Sheathed. AYWY - Aluminium Conductor, PVC Insulated, Galvanized Round Steel Wire Armoured and PVC Outer Sheathed. AYFY- Aluminium Conductor, PVC Insulated, Galvanized Flat Steel Wire (Strip) Armoured and PVC Outer Sheathed Cable. AYCY - Aluminium Conductor, PVC Insulated, Metallic Screened and PVC Outer Sheathed A2XCY - Aluminium Conductor, XLPE Insulated, Metallic Screened and PVC Outer Sheathed. AYCEFY - Aluminium Conductor, PVC Insulated, individual core metallic screened, Flat steel Wire (strip) Armoured and PVC Outer Sheathed. A2XCEFY - Aluminium Conductor, XLPE Insulated, individual cores metallic screened, Flat Steel Wire (Strip) Armoured and PVC Outer Sheathed.

20.   Types of Cables- AYWY, AYWAY, YWY A = Appearing as a first letter denotes Aluminium Conductor. Y = PVC Insulation or PVC Sheath 2X = 2-X (Cross-linked Polyethylene) Insulation. W = Round Steel Wire Armouring . WW = Double Round Steel Wire Armouring . F = Formed Steel Wire (Strip) Armouring . FF = Double Formed Steel Wire (Strip) Armouring . C = Metallic Screening (Usually of Copper). CE = Metallic Screening (usually of Copper) over each individual core. WA = Aluminium Round Wire & Aluminium Formed Wire (Strip) Armouring .

21. Duplex Cable:  The duplex service drop cable is a two core conductor i.e. it has two conductors; an insulated conductor for phase line and a bare conductor for neutral line. Triplex Cable:  The Triplex service drop cable is a three core conductor. It has two insulated conductors for phase line and a bare conductor for neutral line. Quadruplex Cable:   The Quadruplex service drop cable is a quad or four core conductors. It has 4 conductors; three of them are insulated conductors for phase lines and a bare conductor for neutral line. It is used for supplying a 3 phase power supply from the utility pole to the building.

22. RG-6 Coaxial Cable RG-6 is the most common type of coaxial cable used for signal transmission in residential and commercial applications. It is made from a solid copper wire with plastic insulation covered by an aluminum foil and a braided shield for protection against interference.  It is used for audio and video signal transmission in application such as cable TV, Satellite TV signal and radio etc.

23. Hard line Coaxial or Heliax Cable Hard line coaxial or mostly known by its trademark name Heliax cable is a thick coaxial cable with its center solid conductor made from copper and the shield made from copper or silver tubing. It is specifically used for high frequency broadcast transmission. It can carry hundreds of channels and is usually installed between a transmitter on ground and aerial antenna.

24. Unshielded Twisted Pair (UTP) Cable The UTP cables do not have any extra shield for protection against noise. They twisted pairs may reduce the noise but it still affects it. Various categories of UTP cables are used in residential and commercial building with various bandwidth e.g. CAT1, CAT2 etc

25. Shielded Twisted Pair (STP) Cable The STP cable has an extra layer of foil that protects the wires from electromagnetic interferences. They are used for high-end applications where the cables may get affected by external environmental interferences.

26. Single Mode or Mono-mode Fiber Optics Cable This cable allows only one mode of light to transmit. It is made of a very thin single strand of fiber that allows only single light wave to propagate. This decreases the number of light reflection which reduces the attenuation in signal. It provide high transmission rate at long distance with very low attenuation but at high cost.

27. Multi-Mode Fiber Optics Cable This type of fiber optic cable is made of relatively thicker fibers that allow more than one light waves so it can transmit relatively more data. It is used for relatively short distance transmission such as LAN, security system etc

28. Armoured Cable Armoured cables has a protective twisted or braided metallic layer usually made of steel over its conductor. The external sheath is made of plastic. The metallic layer provides extra mechanical strength against any sort of damage and can also be used for grounding connections. The armoured layer can be wire braid, steel wire or steel tape. The steel wire armored cable is most common type of armored cable used for power transmission

29. Armoured Cable

30. Un - Armoured Cable

31. They are mostly used in electronics for data transmission in application such as: Transmitting audio signal to audio mixer. Sending audio and video signal in gaming consoles. Sending camera signal to CCU (camera control unit) in TV studios Sending audio and video signal using a single cable from camera.

32. The sizes of wires used in apartment projects   Point wiring is done with 2 Run x 1.5sqmm + 1 x 1.5sqmm (earth) copper wires. (Wiring between switch point and light /fan point or between light/fan point to light/fan point etc.)   Lighting circuit main is with 2 Run x 2.5sqmm + 1 x 1.5sqmm (earth) copper wires. (Wiring from Distribution board to the first switch point of the particular circuit )   Power circuit main is with 2 Run x 4.0sqmm + 1 x 2.5sqmm (earth) copper wires. (Wiring from Distribution board to the control switches and then from switch to the socket )-16 A Sockets Sub Mains (4 Run x 6 Sq.mm + 4 Run x 2.5 Sq.mm) (3 BHK) & (2 Run x 6 Sq.mm + 4Run x 2.5 Sq.mm) (2 BHK) –EB /DG panel to flat MCB . Power Cables – Govt Sub Station to RMU(Ring Main Unit) Power cables for 11KV application will be 11/11kV grade, 3Cx 400/300 Sq.mm & 3CX240sqmm. Al, AR, XLPE insulated multi core

33. Injuries caused by electric shocks

34. 3 Phase Electrical Wiring Diagram

35. Single Stranded Wire Single stranded wire is made of multiple thin strands of wires that form together one conductor. The stranded design offers flexibility thus they are suitable for applications where wires need to be bent or twisted.

36. Single Solid Wire Single solid wire is made of single solid core with plastic insulation. The solid design offer better connection but it is difficult to bend or twist due to its stiffness. Multiple bending might damage and break the conductor inside. They are used in applications where there is no movement or bending required for wires

37. Underground Feeder Cable: It is a type of non-metallic sheathed cable designed for use in wet location such as supplying power to lamp post or street light

38. Flexible Cables Flexible cables are a type of electrical cables that can withstand continues bending in moving applications. The flexibility is achieved by using stranded conductors. They are used in automation industries where the machines are continuously moving such as pick and place machines and CNC based machines such engraving, milling machines etc

39. Overhead Power Line Overhead power lines are conductors suspended from electrical towers or poles to transmit power over long distance. The conductors used are completely bare and made from aluminum.

40. All Aluminum Conductor (AAC) AAC transmission cable, also known as aluminum stranded conductor is made from multiple strands of hard drawn 1350 aluminum alloy which is 99 % pure with a little bit of silicon, iron etc. it has very high conductivity and resistive to corrosion but very poor strength to weight ratio. That is why it is preferred short distances in the stations not for rural power transmission over long distance All Aluminum Alloy Conductor (AAAC) In order to increase the mechanical strength of the AAC cable, a special aluminum alloy is used made with magnesium and Silicium . It increases the strength to weight ratio while maintaining the corrosion resistivity.

41. Aluminum Conductor Steel-Reinforced (ACSR) Cable ACSR is also a stranded aluminum cable whose inner strands are made from galvanized steel surrounded by strands of pure aluminum conductors. The steel core increases the tensile strength of cable while the aluminum provides good conductivity and low weight. They are used in long distance transmission line because we can alter the strength of its steel core to meet the requirement Aluminum Conductor Aluminum-alloy Reinforced (ACAR) It is made of pure aluminum conductors surrounding an aluminum core. The structure of ACAR resembles ACSR but instead of its core made from galvanized steel, it is made of aluminum alloy which increase the overall conductivity while maintaining the tensile strength if ACSR

42. During transmission of electricity, heat is being dissipated. The heat generated by cables is being minimized via high voltage transmission. The effect of weather and the internal temperature of the cable make it necessary to let the cables a little bit loose. If the cables were made tight and the weather gets cold, it would cause the transmitting cables to contract thereby creating more tension in the cables which might cause it to cut. So, the cables are loose so that even if contraction should occur, there won’t be much tension which would lead to the damage of the cables .

43. 4 Core X 185 Sqmm Aluminium Armoured Power Cable

44. 3.5 C X 300 Sqmm

45. 4 C X 95 Sqmm

46. 2 Core PVC Flexible Cables 2C x 1.5 sq. mm

47. 3C x 1.5 Sqmm

48.   3C x 6.0 Sqmm Copper Flexible Cable

49. 4 Core X 6 Sqmm PVC Insulated Copper Flexible Cable 

50. 6C x 1.5 sq mm

51. 6 Sq mm

52. 1.1 Kv Grade 120 Sqmm , 3.5 Core Aluminium Armoured LT Cable

53. Supply & Installation Cost HT Cable /33KV grade/XLPE/ Aluminium Conductor: Government Substation To RMU Yard: 3C-400Sqmm-Earth Insulated –Rs.3000/ Rmt 3C-300Sqmm-Earth Insulated –Rs.2700/ Rmt 3C-300Sqmm-Un-Earth Insulated –Rs.3200/ Rmt 3C-240Sqmm-Earth Insulated –Rs.2400/ Rmt 3C-240Sqmm-Un-Earth Insulated –Rs.2900/ Rmt 3C-150Sqmm-Earth Insulated –Rs.2000/ Rmt

54. Power circuit wiring : FRLS,2 Runs 4 Sqmm+1 Run 2.5 Sqmm+Conduit-Rs.150/ Rmt Lighting circuit wiring : FRLS,2 Runs 2.5 Sqmm+1 Run 1.5 Sqmm+Conduit-Rs.110/ Rmt Sub main circuit wiring (Electrical/DG panel to flat DB box) FRLS,4 Runs 6 Sqmm+4Run 2.5 Sqmm+Conduit-Rs.340/ Rmt (3BHK) FRLS,2 Runs 6 Sqmm+4Run 2.5 Sqmm+Conduit-Rs.260/ Rmt (2BHK)

55. LT Cables PVC Insulated, XLPE , steel armoured,1100V grade copper conductor 3.5C X 400 Sqmm - Rs.1700/ Rmt 3.5C X 300 Sqmm - Rs.1500/ Rmt 3.5C X 240 Sqmm - Rs.1100/ Rmt Fire Survival cable 3.5C X 300 Sqmm - Rs.1800/ Rmt 3.5C X 240 Sqmm - Rs.1400/ Rmt 3.5C X 185 Sqmm - Rs.1200/ Rmt 3.5C X 150 Sqmm - Rs.1000/ Rmt 3.5C X 95 Sqmm - Rs.800/ Rmt 3.5C X 70 Sqmm - Rs.600/ Rmt 3.5C X 50 Sqmm - Rs.500/ Rmt 3.5C X 35 Sqmm - Rs.400/ Rmt

56. YRY Cable : PVC Insulated, GI strip armoured power cable 4C X 25 Sqmm-Rs.1000/ Rmt 4C X 16 Sqmm-Rs.600/ Rmt 4C X 10 Sqmm-Rs.500/ Rmt 4C X 6 Sqmm-Rs.300/ Rmt 4C X 4 Sqmm-Rs.250/ Rmt 4C X 2.5 Sqmm-Rs.180/ Rmt 3C X 16 Sqmm-Rs.500/ Rmt 3C X 10 Sqmm-Rs.350/ Rmt 3C X 6 Sqmm-Rs.250/ Rmt 3C X 4 Sqmm-Rs.200/ Rmt 3C X 2.5 Sqmm-Rs.150/ Rmt

57. YWY Cable : PVC Insulated, GI armoured ,copper , FRLS power cable 24C X 1.5 Sqmm-Rs.450/ Rmt 24C X 1 Sqmm-Rs.400/ Rmt 6C X 1.5 Sqmm-Rs.180/ Rmt 4C X 10Sqmm-Rs.480/ Rmt 4C X 6 Sqmm-Rs.300/ Rmt 4C X 4 Sqmm-Rs.250/ Rmt 4C X 1.5 Sqmm-Rs.150/ Rmt 3C X 2.5 Sqmm-Rs.180/ Rmt 2C X 2.5 Sqmm-Rs.130/ Rmt 2C X 1.5 Sqmm-Rs.110/ Rmt

58. Thanks & Regards S.Sudha Velan