N2 Electrical Trade Theory: Module 2- Conductors, insulators and cables

Q1 – List 5 requirements of a good conductor. You must ensure that:

Q2 – What do you understand by a conductor?

Q3 – Name ONE important fact about a good electrical joint.

Q4 – What type of joining method will be used for joining flexible conductors and cables?

Q5 – For what type of application is bimetallic ferrules used?

Q6 – Give Three examples of good conductors.

Q7 – Explain why XPLE is such a good insulator

Q8 – Name THREE uses of magnesium oxide

Q9 – Briefly explain the purpose of an insulator

Q10 – Porcelain insulators are covered with a smooth glaze. Why?

Q11 – Glass is a very popular insulator. Explain why

Q12 – Name the colours used in a three-core, flexible type domestic cord and state to which terminals they must be connected

Q13 – Make a neat, labelled sketch of a PVC-insulated, wire armoured cable.

Q14 – Explain the function of the following

a) PVC

b) Wire armouring

Q15 – Are cross linked polyethylene-insulated cables suitable for high voltages?

Q16 – Without referring to the actual joints of the conductors, name THREE requirements of a good joint in an armored cable

Q17 – Name the basic steps to be followed when making a cable joint

Q18 – Name three advantages of installing cables in ducts

Q19 – What does SANS 10142 stipulate with regard to the maximum permissible voltage drop in an installation?

Q20 – Name FOUR disadvantages of buried cables.

Q21 – What does SANS 10142 stipulate with regarding to the jointing of flexible cables?

Q22 – Name THREE functions of the resin used in a high-voltage resin joint.