Capstone - Oral Questions

Question 1

Other than a hot water system, which equipment should have an equipotential bond?

Answer 1

Any metallic parts of equipment that house or otherwise may come into contact with exposed live parts or conductors.

Question 2

What is the minimum size MEN link when the consumer mains are not protected? What AS 3000 clause?

Answer 2

Rated for at least the current carrying capacity of the main neutral conductor. 5.3.5.2

Question 3

Show / Name parts of earthing in the capstone electrical installation.

Answer 3

1 - Earth electrode
2 - Main earth conductor
3 - Main earth bar
4 - MEN link
5 - Protective earth conductors
6 - Equipotential bonds

Question 4

How far from the floor are you permitted to install a main switch? Which AS 3000 clause?

Answer 4

2m.
2.3.3.3

Question 5

Is it permissible to switch or isolate an earthing conductor? Which AS 3000 clause?

Answer 5

No.
2.3.2.1(c)

Question 6

Is it required to identify the neutrals of circuits in a switchboard? Which AS 3000 clause?

Answer 6

Yes.
2.9.5.4

Question 7

Is it permissible to connect a 2.5mm neutral to the load side of an RCD?

Answer 7

Yes, if it’s the only neutral conductor in the RCD.

Question 8

What is the minimum required conductor size for an underground single phase consumer mains, in WA?

Answer 8

10mm.

Question 9

Describe the connection and purpose of the MEN link.

Answer 9

Connect the main neutral and main earth at the (main) switchboard. Allows the main neutral to carry any active to earth fault current.

Question 10

In a domestic switchboard, are all circuit protection devices required to operate in the same direction?

Answer 10

Yes.

Question 11

If no earth link exists at a switchboard, how would you join the protective earths?

Answer 11

Double screw connectors or soldering.