TMA01

Question 1

Specific regulations regarding electrical installations are covered by?

Answer 1

BS 7671 - covers domestic electrical installs

Question 2

What part of the Building Regulations makes specific reference to a person’s competence to carry out electrical installation work?

Answer 2

Part P

Question 3

When bonding to pipework, what does the label state?

Answer 3

“Safety Electrical Connection, Do Not Remove” - all bonding must be identified with green/yellow insulation

Question 4

At the court of a gas meter, the bonding clamp for the main bonding conductor should be installed within?

Answer 4

600mm - earth clamps must be fitted on the consumers side of the pipework, preferably within 600mm of gas meter if practical but within the Building if external

Question 5

Information regarding the minimum conductor size for electrical circuits can be obtained from?

Answer 5

BS 7671 - this also requires that a cable termination of any kind should securely anchor all of the strands of the conductor

Question 6

A branch from a ring final circuit is usually described as a?

Answer 6

Spur - when the extension of the RFC is necessary (such as extra socket or lighting circuit) it may be done using a spur

Question 7

What current rating is required for a protective device of a 9kW shower?

Answer 7

45 A

Question 8

A 3kW immersion heater should be supplied from a protective device in the consumer unit rated at?

Answer 8

15 A fuse or 16A circuit breaker in the consumer unit

Question 9

The supply of a 3kW immersion heater should originate from?

Answer 9

Consumer unit - immersion heaters must be wired on their own individual circuit consisting of 20 A double-pole switch from fixed wiring which is protected by 15 A fuse or 16 A circuit breaker in the consumer unit

Question 10

Which piece of equipment is used to test if an electrical circuit is live?

Answer 10

Voltage Tester to GS38

Question 11

Main equipotential bonding is a method of connecting what to the consumer’s main Earthing terminal?

Answer 11

Extraneous conductive parts - requirement of BS 7671 that all ECPs are bonded together and are connected to the main Earthing terminal that is enclosed within or close to the consumer unit

Question 12

The correct size for main bonding conductor for a TN-S system having 25mm^2 phase and neutral supply conductors is?

Answer 12

10mm^2

Question 13

What is the correct size of fuse to be fitted in the consumer unit of a fused spur supplying a 1kW lighting circuit?

Answer 13

5 A - all fuses should be replaced with one rated at 5 A

Question 14

The colour coding of wiring in a modern 3-core flex is made up of?

Answer 14

Brown, blue and yellow/green - sheath is also grey

Question 15

A ring final circuit should be supplied from a protective device rated at?

Answer 15

30 A or 32 A

Question 16

When installing a surface-mounted cable in a domestic premises, the best installation method is?

Answer 16

PVC mini-trunking

Question 17

A 3kW immersion heater must be provided with a?

Answer 17

20 A double-pole switch

Question 18

When working on any existing electrical system, the first test to be carried out should be?

Answer 18

Voltage test - this must be carried out before starting any work on a circuit to reduce risk of electric shock

Question 19

What test identifies short circuits?

Answer 19

Insulation resistance - IR provides indication of wrong connection, Short-circuits and earth faults

Question 20

The reason a 7kW instantaneous shower is protected by a 32 A mini circuit breaker is the unit’s?

Answer 20

Current rating - high current rating requires a 32 A MCB