Electrical Systems Earthing Quiz

What is one of the main reasons for earthing electrical systems?

• To increase the potential of any part of the system with respect to earth

• To maintain the potential of any part of the system at a defined value with respect to earth

• To prevent current from flowing to earth under any circumstances

• To ensure that in the event of a fault, apparatus normally 'live' can reach a dangerous potential with respect to earth

What does earthing allow in the event of a fault in electrical systems?

• It prevents any current from flowing to earth

• It allows current to flow to earth so that protective equipment will not operate

• It allows current to flow to earth so that protective equipment will operate to isolate the faulty circuit

• It ensures that the faulty circuit remains live and dangerous

What is ensured by earthing in the event of a fault in electrical systems?

• That apparatus normally 'live' can reach a dangerous potential with respect to earth

• That apparatus normally 'dead' cannot reach any potential with respect to earth

• That apparatus normally 'dead' cannot reach a dangerous potential with respect to earth

• That no protective equipment will operate

What is the voltage level at the local substation in the three phase distribution network diagram?

• 230 V

• 400 V

• 11 kV

• 400V Three Phase and Neutral

What is the voltage between any one line and neutral in the three phase distribution network?

• 11 kV

• 400 V

• 230 V

• 400V Three Phase

What color is the line that carries 400V in the three phase distribution network?

• Brown Line

• Black Line

• Grey Line

• Neutral

What does the TN-S system refer to in common earthing arrangements?

• A system with combined neutral and protective conductors

• A system with no neutral or protective conductors

• A system having separate neutral and protective conductors throughout the system

• A system where the protective conductor is earthed at multiple points

What is the cross-sectional area of the protective conductors connected to the metal water pipe and metal gas pipe in the TN-S arrangement?

• 1mm²

• 10mm²

• 16mm²

• 100mm²

What is the rating of the service fuse in the TN-S arrangement ?

• 10A

• 16A

• 100A

• 1000A

What does the abbreviation 'TN-S' stand for in the context of earthing arrangements?

• Transformer-Neutral Separated

• Terra-Neutral System

• Tri-Neutral Split

• Terra-Neutral Separated