conduit trunking tray

• Why is conduit used


  To give cables mechanical protection
• What are the different types of conduit

  • Steel conduit
  • CPC conduit
  • Flexible conduit
• The characteristics of steel conduit

  • Durable
  • harder to bend
  • Has a reasonable weight
  • Doesn't expand more than CPC
  • since its steel it can also be used as a CPC
• What is the BS number for steel


  BS4568
• What is the characteristics of CPC conduit

  • CPC conduit

  - Lightweight easy to handle 

  - Simple to bend

  - Quick installation 

  - PVC solvent adhesive 

  - Expands more than steel 
• What is the characteristics of flexible conduit

  • PVC outer layer
  • Inner layer made of thin spiral of steel/cpc
  • More robust than flex
  • Used in tight and awkward positions
  • is connected between rigid and vibrating instillations
• What are the types of steel conduit

  • Solid drawn
  • Seam welded(made from rolled up stell sheets)
  • Black enamel for dray conditions
  • Galvanised for damp conditions
• What are the types of CPC conduit

  • Light gauge
  • Heavy gauge (thicker walls)
  • oval (thin walls)
• What is the BS number for conduit and fittings 


  BS4568
• What are the conduit accessories

  • 1-4 way box
  • Angle box
  • looping box
  • Dome cover
  • Flexible adaptors
  • Bolt & socket
  • Reducer
  • bar saddle
  • Metal sockets
  • Inspection bend
  • Inspection tee
  • Inspection elbow
  • Lid cover
• What are the more used conduit accessories

  • Coupler
  • Nipple
  • Bras brush
  • Brass female bush
  • Locking ring
  • lock nut
  • brass locking ring
  • Reducer 25mm to 20mm (25 external/20internal thread)
• The advantage of steel conduit

  • Mechanically strong
  • Can be used as a protective conductor
• The advantage of CPC conductor

  • Mechanically strong
  • Doesn't introduce ana earth potential
  • Easier than steel to install
• The advantage of flexible conduit

  • Flexible
  • Isn't damaged by vibrations
• The disadvantage of steel conduit

  • Expensive to install
  • Difficult to change once installed
• The disadvantage of PVC

  • Doesn't like extremes in temperature
  • Can be affected by oils
  • Requires a protective conductor
• The disadvantage of flexible conduit

  • Should only be used for short lengths
  • Not very mechanically strong
  • Requires a protective conductor
• What are the different types of trunking 


  • Metal trunking
  • installing trunking
  • Lighting trunking
  • busbar trunking
  • Under floor trunking
  • Skirting and dado trunking
  • bench trunking
  • Mini trunking
• Why use trunking

  Its usually used instead of conduit because of its ability to carry more cables. It also makes it a more efficient delivery system.
• What is the BS number for trunking

  BS50085
• What to take into consideration when installing trunking


  • Type of trunking
  • Size and capacity
  • Routing and layout
  • Mounting and fixing
  • Spacing and support
  • Cable entry and exit
  • Bending and corners
  • Fire and safety compliance
  • Earthing and bonding
  • Accessibility and labelling
• The purpose of a fire barrier

  The purpose of the fire barrier is to prevent the spread of fire once the containment has passed through a fire break 
• What is the difference between the two busbar trunkings

  One is high current, the other is a low current
• • Underfloor systems are fitted below a raised floor and the interface connections are brought level with the floor
  • This is called segregation
  • The trunking is divided into compartments to separate the power circuits 
• What are the different types of cable trays and racking

  • Joining tray
  • Cable tray ladder rack
  • Cable supports
  • Cable basket system
• Why use a cable tray

  • Only cables that have mechanical protection can be run on cable tray 
  • Cable tray cannot be used as a CPC  
  • Cable tray must be earthed 
  • Used for LV cables
  • Used to deliver SWA and MI cables
  • Easy to bend
  • Supports cables along its run
• The advantages of a cable tray

  • Can support a wide variety of cable trays
  • Very strong
  • Once fixed in position cables can be secured to it
• The disadvantages of a cable tray

  • Can not be used as a CPC
  • Can take lots of up space
  • Doesn't support single PVC cables
• The characteristics of a cable ladder rack

  • Used to support heavy cables
  • Not enclose, providing full mechanical protection
  • Used for insulation electric cables, used for power distribution and communication that can be exposed without extra protection
  • Cables are cleated in position to the ladder system
• Why use cable basket tray systems

  • Used for large number of small cables to be kept tidy, usually band 1 cables
  • has great instillations because of its exposure
  • hold ELV cables
  • High maintenance
• What is the use of Band 1

  
  

  • Protection against electric shock, considering the value of the voltage
  • Holds cables used for fire alarms and emergency lighting circuits
  • Generally holds ELV circuits
  • Instillations where the voltage is limited for operational preposes (telecommunications, etc)
• At what temperature PVC conduit systems not suitable at

  • Above 60°C
  • Below 25°C
• What is the difference between Band 1 and Band 2

  • Band 1 is ELV
  • Band 2 is LV
• What is the use of Band 2

  • Hold LV circuits
  • Used for data cables
  • used in supply households, and most commercial and industrial instillation
• What sizes does mini trunking come as

  Either from: 16x16mm - 50x50mm
• The uses of a basket tray

  • To keep small cables tidy, usually Band 1 cables
• Voltage bands in trunking

  • There two types of bands: Band 1(ELV) and Band 2(LV)
  • When installing the cables, the two band must be kept separated, as two different level voltages run through them