Appendix F

• At what temperature should thermoplastic not exceed

  70°C at the conductor
• At what temperature should thermosetting (XPLE) not exceed

  90°C at the conductor
• The instillation methods & related reference methods

  • Method A: Cables in multi-core cables in a thermally insulated wall
  • Method B: Cables enclosed in trunking or conduit
  • Method C: Clipped direct
  • Method D: Cable laid direct in the ground
  • Method E/F: On a perforated tray
• What are the Rating Factors

  • Ca
  • Cg
  • Ci
  • Cf
  • Ib
  • In
  • It
• What is Ca

  Ambient temperature
• What is Cg

  Grouping
• What is Ci

  Thermal instillation
• What is Cf

  For BS3036
• What is ambient temperature

  Air temperature other than 30°C to be applied to the current capacities for cables in free air, given in Appendix F Table F1 rating factors
• what are the types of grouping

  • Touching on a perforated tray system
  • Bunched
  • Enclosed
  • On a surface
• What is thermal instillation

  
  

  • Cables in contact with a thermally conductive surface on one side
  • Material reduces the current-carrying capacity of any cable it may cover
• What is rating factors used for 


  Its used to calculate a cable-size that must be applied where a BS3036 (rewireable) fuse is used
• Voltage drop in consumer's instillations

  
• Units

  
• Current-carrying capacity formula

  
• 1. Calculate the design current of the circuit to find(It≥In≥Ib)

  Ib = P/V = 6500/230 = 28.26 Amps = (round up) 30 Amps = In=30 Amps

  2. Find which rate factor we need to use

  3. 30/0.94 x 0.725 = 44.02A = It=44.02A

  
• What is Ib


  Its the design current of the circuit (the current intended to be carried) 
• What is In


  Its the rated current or current setting of protective device (CLOSES SIZE MCB ) 
• What is It


  Its the tabulated current-carrying capacity of a cable (Current that flow circuit)