1. Electrical Installation-Module 3
Electrical Installation Drawings

2. Module Objectives:
state the purpose of electrical installation drawings.
differentiate between installation/wiring diagrams and circuit/schematic diagrams
identify the symbols and terminology used in installation and schematic diagrams.
implement electrical installation drawings.

3. Why do we need electrical installation drawings?
The ability to read and understand schematics and drawings is an absolute must.
Electrical installation drawings provide an electrician with the technical information needed to install the wiring system in apartments or buildings.

4. Electrical Installation Drawing Types
Installation or wiring Diagrams
Schematic or Circuit Diagram
Does not show the functional details of the electrical installation
show the functional details of the electrical installation interconnections

5. Installation & Wiring Diagram
The Installation diagram or Wiring diagram is a detailed diagram that shows the electrical or electronic components, connectors, connecting wires.
It also identifies the wires by wire numbers or color coding.

6. Installation/Wiring Diagram Symbols
Connection Line
Protective earth line
Signal line
Distribution device
Junction box
Lines Symbols
Safety devices Symbols

7. Installation/Wiring Diagram Symbols
Number of wires/cable
Lamp
Pushbutton
Socket outlet, single phase
lines
Safety and reliable devices

8. Installation/Wiring Diagram Symbols
One gang one way switch
Two gang one way switch
One gang two way switch
Intermediate switch
Switches Symbols
Switches Symbols

9. Switches Terminology One light operated by one switch
One light operated by two switches
One gang one way switch
One gang two way switch
Two one way switches in a single module
Switch of 4 terminals used to control device from more than two locations.
Two gang one way switch
Intermediate switch

10. Activity -1

11. Activity -1 One gang one way switch One gang two way switch
Two Gang one way switch
Socket
Intermediate switch
Lamp
Connection line

12. Lab Activity 1 –Page 11 – Module 3
Homework

13. Schematic Diagram
Schematic diagrams show the electrical systems, and are used for understanding the electrical functions of a wiring system.
The schematic is a representation of how the circuit works.
the schematic shows the logical order of how they are used together.

14. Schematic Diagram Symbols
Connection Line
Protective earth line
Signal Line
Line to indicate component housing
Fixed Connection
Movable Connection
Terminal Connection Strip

15. Schematic Diagram Symbols
Junction box
Earth connection
Electric fuse
Electric lamp
MCB
Socket outlet, single phase
Pushbutton

16. Schematic Diagram Symbols
One gang one way switch
Two gang one way switch
One gang two way switch
Intermediate switch
One gang one way two pole switch

17. Electrical Installation Drawing Examples
The Wiring Diagram Shows that one lamp in this room is operated by one switch
In the schematic diagram each individual connection line is shown and more detailed graphical symbols are used to indicate the electrical details of a wiring.
Wiring Diagram
Schematic Diagram

18. Electrical Installation Drawing Examples
The room has two doors so the lamp is operated by two switches
More detailed graphical symbols for the interconnections
Wiring Diagram
Schematic Diagram

19. Wiring Vs Schematic Architectural plan shown.
Does not show the functional details of the electrical installation.
Architectural plan not shown.
Details such as the interconnection of components like switches, Junction boxes, light fittings etc. will be shown.
Wiring Diagram
Schematic Diagram

20. Lab Activity 2 & 3 – Page(12-13) – Module 3
Classwork

21. Module Exercises – Page 14
Homework
The End