Installation Theory

What are the 4 common sizes of conduit ?

• 15, 20, 25, and 30 mm

• 15, 22, 25, and 30 mm

• 16, 20, 22, and 32 mm

• 16, 20, 25 and 32 mm

What type of lamp cap is shown?

• Bayonet

• Two pin

• Edison

• Twist

With the test instrument set to MΩ, what dead test is carried out?

• Insulation resistance

• Earth fault loop impedance

• Continuity of CPC and polarity

• Continuity of final circuits

According to the On-site Guide the first four dead tests in order are..?

• Polarity, insulation resistance, continuity of protective conductors, continuity of ring final circuits.

• Insulation resistance, polarity, continuity of ring final circuits, continuity of protective conductors.

• Continuity of protective conductors, continuity of ring final circuits, insulation resistance, polarity.

• Insulation resistance, polarity, continuity of protective conductors, continuity of ring final circuits.

What is the maximum volt drop allowed for socket outlets in a domestic property?

• 11.5 V

• 110 V

• 6.9 V

• 230 V

Which earthing system uses an earth rod as the main point of earthing at the consumers end of an installation?

• TT

• TN-S

• TN-C-S

• TN-S-S

Which one of the following is an exposed conductive part ?

• Metal water pipe

• Radiator

• Metal clad light switch

• Metal frame of the building

The main function of the earthing system of an installation is to...?

• Stop the risk of fire

• Reduce the risk of overloads

• Reduce the risk of of electric shock

• Reduce the conductor size

Typical rating for an overcurrent protective device for domestic lighting is ?

• 15 A

• 32 A

• 25 A

• 6 A

A circuit in which the line conductors start and return to the same protective device within the consumer unit is ?

• Radial circuit

• Ring final circuit

• Lighting circuit

• Sub-main circuit