Results 1 to 5 of 5

Thread: triple pole breaker for a single phase supply

  1. #1
    New Member
    Join Date
    Aug 2015
    Location
    capetown
    Posts
    7
    Thanks
    5
    Thanked 0 Times in 0 Posts

    triple pole breaker for a single phase supply

    When doing Inspection and Testing for a CoC for a domestic Installation for a house that used to have a three phase supply now with single phase through a TP MCB. is this legal and what Reg can I use to support this.

  2. #2
    Site Caretaker Dave A's Avatar
    Join Date
    May 2006
    Location
    Durban, South Africa
    Posts
    22,648
    Thanks
    3,304
    Thanked 2,676 Times in 2,257 Posts
    Blog Entries
    12
    What you need to pay attention to in particular is 6.9.2.2.

    With a 3 phase installation, the disconnecting device need not disconnect the neutral in a TN system.
    With a single phase system, both the live and neutral must be disconnected.

  3. Thanks given for this post:

    jkamuz (23-Sep-15)

  4. #3
    New Member
    Join Date
    Aug 2015
    Location
    capetown
    Posts
    7
    Thanks
    5
    Thanked 0 Times in 0 Posts
    Well that is a good point. Thanks Dave A

  5. #4
    Diamond Member AndyD's Avatar
    Join Date
    Jan 2010
    Location
    Cape Town
    Posts
    4,923
    Thanks
    576
    Thanked 934 Times in 755 Posts
    Quote Originally Posted by Dave A View Post
    What you need to pay attention to in particular is 6.9.2.2.

    With a 3 phase installation, the disconnecting device need not disconnect the neutral in a TN system.
    With a single phase system, both the live and neutral must be disconnected.
    Would the regs forbid using a t/pole MCB to do this?
    _______________________________________________

    _______________________________________________

  6. #5
    New Member
    Join Date
    Aug 2015
    Location
    capetown
    Posts
    7
    Thanks
    5
    Thanked 0 Times in 0 Posts
    I haven't seen anywhere in the regs where it specifies that you cannot use a TP for a single phase, but in most cases you find that, most sparkies would not consider protection of the cable etc.

Similar Threads

  1. 3 phase moor/2 phase supply
    By Leecatt in forum Electrical Contracting Industry Forum
    Replies: 1
    Last Post: 17-Jul-15, 01:24 AM
  2. [Question] Three phase vs single phase
    By Solarfan in forum Electrical Contracting Industry Forum
    Replies: 16
    Last Post: 02-Jul-15, 05:05 AM
  3. Three phase to single phase generator advice needed
    By joshthejew in forum Electrical Contracting Industry Forum
    Replies: 3
    Last Post: 08-Apr-15, 10:12 PM
  4. [Question] Three phase / Single phase
    By Martinco in forum Electrical Contracting Industry Forum
    Replies: 9
    Last Post: 14-May-12, 10:57 PM
  5. [Question] Single phase and 3 phase testing course
    By skatingsparks in forum Electrical Contracting Industry Forum
    Replies: 3
    Last Post: 26-Feb-09, 09:14 AM

Did you like this article? Share it with your favourite social network.

Did you like this article? Share it with your favourite social network.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •