Inspection and test - Paper 4

GN3 gives the maximum stable value of Ze for a TT installation as:

• 1660 ohms.

• 600 ohms.

• 200 ohms.

• 100 ohms.

Which type of earthing system relies on a separately supplied earth, usually the sheathing on the cable:

• TT.

• TN-C-S.

• IT.

• TN-S.

Which of the following would not be one of the human senses to use during the initial verification of an addition to a lighting circuit:

• sight.

• hearing.

• taste.

• touch.

On a standard TT installation, the result of the resistance of the earth electrode and the rated RCD residual operating current should not exceed:

• 25V.

• 50V.

• 110V.

• 400V.

Which of the following protection devices is unlikely to be suited for short circuit currents in the region of 6kA: GN3

• BS 3036 semi-enclosed fuse.

• BS 88-3 cartridge fuse.

• BS 88-2 general purpose fuse.

• BS EN 60898 circuit breaker.

The person carrying out inspection and testing must have: GN3 1.2

• an inspection and test qualification.

• sound knowledge and experience relevant to the installation being inspected.

• both (a) and (b).

• a current Wiring Regulations qualification.

A British Standard having a BS EN number is a:

• European harmonised Standard.

• Non-statutory Regulation.

• British compliant Standard.

• Statutory Regulation.

The top surface of a consumer unit should be protected from ingress of dust to a standard of:

• IP2X.

• IP4X.

• IP5X.

• IP6X.

A visual inspection is necessary before testing to check whether:

• there is adequate access to switchgear.

• the Zs is within the maximum allowed.

• the polarity of switches and fuses are correct.

• the insulation resistance is acceptable.

During initial verification of a TN system the installation earth conductor was recorded as 16mm2. The minimum size of main bonding conductor should be: BS7671 CH54

• 4mm2.

• 6 mm2.

• 10 mm2.

• 16 mm2.