1. EGD ELECTRICAL
ELECTRICAL SYMBOLS

2. Distribution board

3. This board houses all the trip switches for the various circuits as well as the earth leakage relay or unit.
It can also house other units such as timers or even an electricity meter.

4. Earth

5. Used together with Earth leakage unit.
This unit detects a leakage of electricity down to earth.

6. One way switch single pole

8. One way switch Double pole

9. One way switch Three poles

10. Two way switch

11. Regulating switch e.g. dimmer

12. SWITCHES
This device comes in various shapes and is used to break the flow of current in a circuit

13. Socket outlet

14. Switched socket outlet

15. Allows the user to plug in different electrical appliances.

16. Fluorescent lights x 40W

17. Lights – Bulb type

18. Lights – wall mounted

19. Light types include bulbs and tubes.
Energy efficient lighting uses less electricity.
BULB: A bulb lights up when current flows through it, and is not polarised.

20. Light Emitting Diode

21. Light Emitting Diode or LED
It lights up when current flows through it,
but is polarised, and will not work if connected incorrectly.

22. AMPERE AND VOLT METERS A V

23. VOLT (V) This unit is used to measure electrical pressure.
AMPERE (A) This unit is used to measure the amount of current flowing in a circuit
Every appliance connected to a circuit will draw a certain amount of current when in operation.
VOLT (V) This unit is used to measure electrical pressure.
The single phase voltage used in SA for domestic use is 220 Volts

24. CELLS AND BATTERIES

25. Two or more cells, connected together creates a battery.
A cell is a single unit.
Two or more cells, connected together creates a battery.

26. Mains switch (Industrial)

27. Mains switch controls the power supply to the distribution board.
Mains switch controls the supply inside the distribution board, to all the different circuit breakers inside the distribution board.

28. Fuse

29. This device is used as part of protection for electrical devices.
This device is used to break the flow of electricity whenever a circuit is overloaded.
This device is used as part of protection for electrical devices.
Must be replaced when blown.

30. Circuit breaker

31. Performs the same function as a fuse.
When the switch trip, it only needs to be reset and not replaced.

34. Single pole single throw

35. Single pole, double throw

36. This device comes in various shapes and sizes
This device is used to break the flow of current in an electrical circuit.

38. Push to make switch

39. Push to break switch

42. release to break switch. NO (normally open circuit)
PUSH TO MAKE SWITCH,
release to break switch.
NO (normally open circuit)
PUSH TO BREAK SWITCH,
release to make switch.
NC (normally close circuit)

43. Symbol for ON / OFF

44. Resistors

45. A resistor limits the amount of current flow in a circuit.
These values are indicated by a series of coloured bands on them

46. Power supply types

47. AC is the abbreviation for alternating current.
AC is the electricity supplied to our homes and industry
DC is the abbreviation for direct current.
DC is the type of electricity supplied by a cell or battery.

48. Buzzers and bells

49. A buzzer or a bell converts electrical current into a sound wave.
Can be used as a warning indicator

50. Transformer

51. Can only be used with AC cycle.
A transformer consist of coils, using the magnetic field created by the flow of the electricity input on the primary side.
It is use to step up (rise) or step down (lower) the supply of electricity on the secondary side.
Can only be used with AC cycle.

52. Capacitor- Electrolytic or non electrolytic

53. It is use to store electrical current
and the capacitor will then supply the stored current when needed.

54. Motor M

55. A motor uses electromagnetism to produce movement when the motor is connected to electricity.
In DC motors, if the polarity is changed, the motor will rotate in the opposite direction.

56. Geysers G

57. Water is heated by means of a thermostat regulated element.
Provides hot water.
Water is heated by means of a thermostat regulated element.

58. Aerials

59. Different types of aerials can be used for sending and receiving of radio waves and signals.

60. ELECTRICAL
CIRCUIT
(1)