Domestic Installation

What is the main purpose of earthing in an electrical installation?

• To increase the risk of using electricity

• To protect the consumer from electric shock

• To reduce the cost of electricity

What parameters influence on hotel energy consumption? Odd one out

• Physical parameters

• Exterior and interior design

• Operational parameters

The symbol for Total earth loop impedance is?

• Zs

• Ib

• Iz

• Ze

What is the maximum recommended floor area for a final circuit designated an A2 radial within the IET On-Site Guide?

• 25m2

• 50m2

• 75m2

• 100m2

What is the British standard number for the IET Wiring Regulation?

• BS 5626

• BS 5839

• BS 7671

• BS 7909

Which of the following is an example of extraneous-conductive-parts

• Steel conduit

• Steel Trunking

• Steel Tray

• Steel duck work

Additional protection applies to: (more than 1)

• cables in metal enclosures

• SWA

• cables embedded > 50mm

• cables embedded < 50mm

What earthing system do we practice in Ghana?

• TNC-S System

• TNC System

• TT System

• Earth Electrode and mat System

What is the maximum value for Ze, for a TN-C-S system?

• 0.8

• 0.35

• 20

• 1666

Which devices will detect an imbalance between the line and neutral, overload and all type of overcurrent fault?

• RCD

• RCBO

• CB

• BBC