18th Edition Part 5 Mock 2

Where a private source for a safety service can operate in parallel with the public supply systems, permission to operate the source must be obtained from?

• a)        The installation designer
• b)       The duty-holder
• c)        The distribution network operator (DNO)
• d)       The heaIth and safety executive

Three circuits can share the same ducting system, provided?

• a)        Every cable is insulated to the highest voltage present
• b)        Only plastic ducting is used
• c)        The ducting has partitions
• d)       The cables are separated by 500 mm

An installation includes a d.c. power circuit with a grey coloured cable, which terminal does this cable connect to?

• a)        Positive
• b)        Earth
• c)         Negative
• d)        Mid-wire

A powertrack system shall be installed in accordance with the manufactures instructions, taking into account?

• a)        The number of bunched circuits
• b)        The maximum prospective fault current of the conductors
• c)        The external influences
• d)        The maximum temperature rating of the track

An RCD is to be used to provide protection against electric shock, the RCD shall be capable of disconnecting?

• a)       The neutral conductor
• b)       The live conductors
• c)        The line conductors
• d)       The cpc

It can be considered that the neutral conductor may carry a significant electric current in a three-phase system when a third harmonic current is present with a harmonic distortion greater than?

• a)        1°/o
• b)      5°/o
• c) 10°/o
• d) 15°/o

What is the minimum cross-sectional area of an unscreened multi-core copper conductor used for data transfer?

• a)                  0.1 mm2
• b)                 0.2 mm2
• c)             0.4 mm2
• d)                  0.5 mm2

Firefighter's switches are red, as they are used for isolating an installation to remove any unexpected danger. Where does it state they should be red?

• a) 511.2
• b) 560.9
• c) 537.3.3.5
• d) 541.3

When a ceiling rose is fitted in a lighting circuit it shall comply with?

• a)              BS 67
• b)            BS 6972
• c)              BS EN 60598
• d) BS EN 60309-2

Which one of these is not a recognised power source for a generating set?

• a)       Combustion engine
• b)        Electrochemical accumulator
• c)        Electric motor
• d)       The public mains supply