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Worksheets305 wb 1
Total questions: 40
Worksheet time: 20mins
Which of the following is a domestic installation?
Hospital operating theatre
Office block
Private house
Petrochemical refinery
Steel conduit is commonly used because it:
Is flexible and low cost
Provides high resistance to mechanical stress
Is only for agricultural sites
Cannot be used in commercial buildings
A plastic conduit system is:
Stronger than steel conduit
Easier to install but less robust than steel
Used only outdoors
Illegal for schools
Cable tray is typically used when:
Only one cable needs to be supported
Cables must be individually clipped
Supporting multiple cables is required
Working in agricultural premises only
A ladder rack is stronger than a tray and usually applied in:
Domestic kitchens
Industrial sites with large sub-main cables
Schools
Agricultural barns only
Basket tray is mainly suited for:
Large industrial sub-mains
Supporting smaller cables in commercial premises
Solely domestic cabling
Armoured underground cables
When selecting a wiring system, which of the following is NOT a factor?
Voltage
Nature of location
Colour of paint on walls
Electromechanical stresses
Regulation 132.7 states wiring selection must consider:
Fire risks, electromagnetic interference, mechanical stresses
Only the price of materials
Contractor preference
Colour coordination
The most common conductor material for cables is:
Aluminium
Copper
Steel
Brass
PVC insulation is widely used because it:
Is naturally fireproof
Provides versatile insulation for conductors
Never becomes brittle
Eliminates need for protection
PVC becomes brittle when exposed to:
High humidity
Freezing temperatures
Constant vibration
Electrical surges
The maximum operating temperature of thermoplastic PVC is:
50°C
70°C
90°C
120°C
XLPE (thermosetting PVC) can operate continuously at:
50°C
70°C
90°C
150°C
Low Smoke and Fume (LSF) cable is required in:
Schools and offices
Domestic kitchens
Farms
Garden lighting
A PVC single core (6491X) cable is typically installed:
Without protection
Inside conduit or trunking
As overhead lines
In prefabricated housing only
PVC twin and earth (6242Y) cable typically contains:
Only insulated conductors
Two insulated conductors plus an uninsulated cpc
No cpc at all
Aluminium sheathing
PVC flexible cable (3092Y/3093Y) is mainly used for:
Underground power supply
Connecting portable appliances
Distribution boards
Industrial sub-mains
When terminating flexible cable, strands must be:
Cut shorter than insulation
Twisted to prevent whiskers
Left untwisted
Soldered every time
Tri-rated cable is preferred in switchgear because:
It withstands 70°C only
It is flexible and approved to UK, US, and Canadian standards
It can only be used outdoors
It eliminates all need for conduit
Which insulation type withstands the highest continuous temperature?
Butyl rubber
Silicon rubber
Glass fibre
Thermoplastic PVC
SWA cable can be:
Buried directly in the ground
Only used indoors
Installed without protection in rivers
Never used between buildings
SWA is commonly used for:
Fire alarms
Sub-main distribution circuits
Pendant lighting
Decorative wiring
The armour in SWA cable:
Provides mechanical protection and can serve as cpc
Is made from copper strands
Must always be insulated
Is for decorative purposes
When using SWA as cpc, you must confirm:
The armour has equivalent CSA to copper cpc
Armour is painted green
No insulation is present
The armour is waterproofed
SWA can be supported by:
Ladder racks and cable trays
Plastic baskets only
Wooden battens
None of the above
MICC cable is commonly called:
FP200
Pyro
Armoured flex
Flextray
MICC cable insulation is made of:
Polyethylene
Magnesium oxide powder
PVC plastic
Silicon rubber
An advantage of MICC cable is:
Low cost
Fireproof and waterproof
Easy terminations
Lightweight plastic armour
A disadvantage of MICC cable is:
Moisture absorption and complex termination
Poor fire resistance
Limited current capacity
Weak mechanical strength
FP200 cable is widely used for:
Decorative lighting
Fire alarms, emergency lighting, and essential services
Underground sub-mains
Switchgear connections only
FP200’s insulation is made from:
PVC
Insudite composite material
Glass fibre
Rubber
The CWZ fire test standard (BS 6387:1994) covers:
Fire, water, and mechanical shock resistance
Only electrical conductivity
Armouring thickness
Colour of cable sheath
FP200 cable is considered relatively cheaper than:
MICC
PVC twin and earth
SWA
Basket tray systems
A disadvantage of silicon-insulated FP cables is:
They require ferrules because of brittleness
They cannot be terminated
They corrode easily
They are not waterproof
Multi-core insulated and sheathed flexible cords are typically used for:
Fixed wiring only
Portable equipment
Substation feeders
Underground high voltage lines
The abbreviation cpc stands for:
Conductor protective cover
Circuit protective conductor
Cable protective casing
Current potential core
Which of the following is a fire resistant cable?
6242Y twin and earth
6491X single core
FP200
3092Y flex
Bell wire is commonly used for:
High-voltage distribution
Chimes and doorbells
Fire alarms
Underground mains
Which factor increases cable flexibility?
Larger conductor size
Use of many fine strands
Armour thickness
PVC sheathing
The main advantage of tri-rated cable in industry is:
Approval across multiple international standards
Cheaper than all other cables
No insulation required
Used only in farms
