Slide Presentation of Electrical System.

Electrical

1. BAQS 3290 Principles of Estimating for Building Services and External Works 1 Topic: Electrical Works

2. OUTLINE 2 Purpose of M & E Measurement Electrical Installations and Main Components Electrical System Lighting System Domestic Distribution Wiring System Fittings and Accessories Cost Factors – Materials Cost Factors - Labour

3. Purpose Of M & E Measurement 3 To determine elements and components involved in M & E works To estimate with relation to SMM2 To protect the interest of the client and the contractor A tool for cost control in mechanical and electrical services. To minimize future disagreements

4. Electrical Installations and Main Components 4

5. Types of electrical works installation 5

6. Single and Three Phase Theory 6

7. Main Components Electrical Distribution 7

8. Electrical Distribution in Building 8

9. Main Components Electrical Installations 9

10. Electrical System 10 Protection against electric shock designed to prevent persons and livestock from direct contact with live parts of the installation preventing a current from passing through the body of the person or livestock or alternatively, by limiting the current which can pass through the body to a safe value automatic disconnection of the supply in a determined time

11. Electrical System 11 Protection against thermal effects electrical equipment shall not become so hot as to present a risk of burns to persons or livestock. electrical installation shall not pose a risk of ignition of flammable materials due to high temperature caused by the electric.

12. Electrical System 12 Protection against overcurrent excessive temperatures or high electromechanical stresses maybe produced that can cause injury to persons or livestock and damage to property disconnect an overcurrent situation; and limit the maximum overcurrent to a safe value and duration.

13. Electrical System 13 Erection and initial verification of electrical installation good workmanship carried out by qualified personnel using proper materials identification of conductors, reliable electrical connections and measures taken to eliminate risk of fire

14. Electrical System 14 Division of installation divided into several circuits to avoid danger and minimise inconvenience in the event of an electrical fault it facilitates safe investigation and testing

15. Electrical System 15

16. Electrical System 16 Protection against direct contact: Insulating the live parts covering the live parts with insulation Use of barriers or enclosures Placing out of reach Earthing Combustible constructional materials cause a fire to the walls, floors and ceilings

17. Electrical System 17 Fire propagating structures some structures may facilitate the spread of fires recommended to install fire detectors Protection against overheating ensure that the required airflow be established before the heating elements are activated when the air flow is stopped, the heating element shall be stopped two temperature limiting devices, independent of each other, shall be installed to prevent permissible temperatures from being exceeded

18. Electrical System 18 Wiring system an assembly consisting of cables, busbars or cable trunkings and parts, which secure, support or enclose them components including cables and wiring accessories shall be installed at temperatures within its limits

19. Electrical System 19 Wiring system protected from heat sources by: shielding; placing sufficiently far from heat source; selecting a wiring system rated for the effects of the heat source; and local reinforcement or substitution of insulating material. Examples of heat sources are hot water systems or steam pipes; manufacturing process; and the sun.

20. Electrical System 20 Wiring system not to be damaged by water make provisions for the water to escape not to be damaged by solid foreign objects dusty environment corrosive or polluting environment protected or made from materials resistant to these detrimental substances

21. Electrical System 21 Wiring system minimise the damage due to mechanical stress, e.g. install a steel plate to protect the wiring system by impact care shall be taken that the cable connections are not compromised by vibration use of cables with a flexible core

22. Electrical System 22 Wiring system care shall be taken that the cable connections are not compromised by vibration use of flexible conduit use of flexible trunking

23. Electrical System 23 Socket Wiring system

24. Electrical System 24 Single Phase Source: Suruhanjaya Tenaga, A Guidline for Electrical Wiring for Residential (2014)

25. Electrical System 25 Three Phase Source: Suruhanjaya Tenaga, A Guidline for Electrical Wiring for Residential (2014)

26. Lighting System 26 Lighting designers must consider eight key factors when specifying lighting systems The owner's project requirements (OPR) that include project costs and schedule The basis of design (BOD) Codes and standards, including energy guidelines Sustainability certifications (GBI, etc.) Recommended lighting levels Lifecycle costs Safety and security Maintenance and warranty

27. Lighting System 27 building occupants do not necessarily want LEDs or wireless control—they want to be comfortably seeing what they are doing enhancing the architecture, integrating with the available daylight, minimizing building energy use, and aligning with the overall construction process and budget 

28. Lighting System 28 illuminate the architectural forms and surfaces

29. Lighting System 29 criteria for both quantity and quality of light depend on the type of task performed in each space and work area

30. Lighting System 30 interior design choices, such as surface finishes, can have a dramatic impact on the lighting system and how much light is required to make a space feel bright visual elements of lighting equipment must also coordinate with the interior design

31. Lighting System 31

32. Lighting System 32

33. Compound Lighting 33

34. Compound Lighting 34

35. Taking-off List for Electrical Installations 35

36. 36 Internal – domestic Distribution board

37. 37 Internal – domestic Sub-circuit DB to sub DB Final sub-circuit Sub DB to fittings

38. 38 Distribution Boards

39. 39 Trunking Conduit

40. 40

41. 41 Conduits

42. 42 Power outlet Switches

43. 43 Switches, Socket and points

44. 44

45. Taking-off List for Electrical Installations (cont’d) 45

46. Electrical System 46 Manufactured equipment and fittings: Switches Socket outlets Cable outlets Light fittings Connected by Electrical cables of various sizes

47. Electrical System 47 Labour: Delivery Storing Setting or supporting during installation Connecting equipment, outlets and fittings

48. Cost Factors - Materials 48 Wiring Trunking/conduit Installation route In wall – chased In celing In floor Fittings

49. Cost Factors - Materials 49 Wiring – Factors that affect the cost of wiring Type of the building Size of the building Arrangement of the buildings Materials used in the construction of the building Building frame (Steel, masonry, concrete)

50. Cost Factors - Materials 50 Wiring – Factors that affect the cost of wiring per outlet Length run betwe e n outlet Kind of installation Size of wire required Type of conduit used Materials Labour

51. Cost Factors - Materials 51 Wiring – Item to be included in the Cost of Wiring Service Wire Meter Box Switch Box Conduit Wire Switches Sundries Supplies (where necessary)

52. 52

53. 53

54. 54

55. Cost Factors - Labour 55 Labour Factors There are three (3) approach to estimate labour cost for wiring: Cost per outlet Percentage from cost of materials Time required to perform the task/ labour constant

56. Cost Factors - Labour 56 Labour Factors Cost per outlet

57. Cost Factors - Labour 57 Labour Factors Time required to perform the task Normally requires two labour, an electrician and a helper (semi-skilled). Labour-hour

58. Estimating for Electrical Works 58 Materials Fittings and Accessories Cables (times 2 – thru and for/ or sometimes 3 depending on the specification) Conduits Total of all material cost to add wastages Labour Cost Testing and Commissioning Overhead and profit