18th Edition appendices mock 1

A circuit uses a 45-amp BS 88-3 cartridge fuse as a means of protection, what is the tabulated disconnection time for an overcurrent of 550 amps?

• a)        0.1 second
• b)        0.2 second
• c)        0.4 second
• d)        1.0 second

Which BS standard covers ceiling roses?

• a)         BS 5655
• b)            BS 67
• c)              BS EN 81
• d)         BS EN 50438

Which is the principal organisation responsible for 'Distributors Installations' in the UK?

• a)             The heaIth and safety executive
• b)             The local authority organisation
• c)             The department for innovation and skills
• d)            The home department

The group rating factor for a group of five different sized sheathed cables is?

• a) 0.325
• b) 0.447
• c) 0.528
• d) 0.632

With reference to energy efficiency systems, on-site renewable energy sources?

• a)     Increase the efficiency of an electrical installation
• b)      Reduce the efficiency of an electrical installation
• c)      Reduce the overall public electricity network losses
• d)     May be considered a direct energy efficiency measure

When measuring the prospective fault current in a three-phase installation the highest prospective fault current will occur?

• a)      When a short circuit develops between a line and neutral conductor
• b)      When a short circuit develops between a line and earth conductor
• c)      When a short circuit develops between two-line conductors
• d)     When a short circuit develops simultaneously between all line conductors

With reference to AC motors used within an energy efficiency system, what method can be used to achieve higher energy efficiency?

• a)     Install less powerful motors
• b)     Install more powerful motors
• c)     Install variable speed drives
• d)     Install fixed speed drives

With reference to energy efficiency system, to obtain a load profile, measurement of energy used should be recorded over a minimum period of?

• a)     1 hour
• b)     5 hours
• c)      12 hours
• d)     24 hours

With reference to energy efficiency systems, consideration should be given to improving load power factor to?

• a)     Reduce tariff penalties
• b)     Reduce the harmonic distortion in the system
• c)      Reduce the maintenance required
• d)     Reduce the impulse withstand voltage

A 70°C thermoplastic cable is ran in free air through a bakery with an expected ambient temperature of 40°C. What cable-rating factor should be applied to the current carrying capacity?

• a) 1.00
• b) 0.94
• c) 0.87
• d) 0.79