Understand standard lighting circuits

• What are the three general types of artificial lighting

  • Incandescent
  • Discharge
  • LED
• The types of light circuit method

  • Three plate ceiling rose method
  • Loop-in method
  • Joint/junction box
• How does a Three plate ceiling rose work

  A twin & earth cable is run to all the lighting points and control points as a radial circuit
• In a three plate system, why is brown sleeving used

  Its used to identify that the cable is being used as a line conductor
• What use is a Loop-in method

  
  

  • The loop-in method using conduit/trunking is the easiest method, because we can use single core cables
  • Best to remember to supply the line(live) to the switch, and neutral cable tot the lamp. Make sure not to mix them up
• What is the purpose of the joint/junction box

  
  

  • It brings all the cables to a common point and makes all the connections there.
  • In summary, electrical junction boxes are vital for safety, organization, and maintenance. They protect connections, prevent hazards, and ensure the reliability and efficiency of the overall electrical system
• What are the types of circuit systems

  • Three plate ceiling rose method
  • loop-in method
  • Joint/Junction box
• Three plate ceiling rose method

  
• The three plate system

  
• Loop-in method

  
• Loop-in method diagram

  
• Joint/Junction box

  
• What types of switches are used in a lighting circuits


  • One way switch
  • Two switch
  • Two way, two gang switch
  • Intermediate switch
• Types of pole-switches

  
• Types of pole-switches

  
• Socket outlet circuit

  
• Common system types


  • PVC/PVC twin and cpc, domestic
  • Conduit/Trunking, PVC singles, commercial/industrial
  • MI & SWA, specialist and outdoors
  • Modular system - increasingly used (given many more lighting options through micro processor control)
• Luminaire types


  • Pendant, LED, halogen - domestic
  • Surface - mounted batten or modular fluorescent - office/commercial
  • Suspended/recessed halogen - shops
  • Halogen strips - outdoor security and construction sites
  • High-pressure sodium or metal halide - stadium and street
• How does Incandescent work

  The emission of light caused by heating the filament
• How does Discharge work

  Produces light by means of an electric arc between tungsten electrodes housed inside a transparent tube, filled with noble gas and often also contains metals metal salts
• How does LED work

  Semiconductors device that converts electricity into light
• What are the different methods of a Three plate ceiling rose method

  • There is a permanent live conductor and neutral conductor at each of the lighting points unless it is switched with the main lighting points
  • A twin & earth cable is run to each of the switches for one way control
  • A three core & earth cable is run between the switches for 2way switching and or 2way & intermediate switching
• What does a junction box provide

  • Safety and protection
  • Containment of electrical connection
  • Organizing and managing wiring
  • Compliance with electrical codes
  • Facilitating changes and repairs
  • Connection points
  • Distribution of power