IET logo
 
IET
Decrease font size
Increase font size
Topic Title: Earthing Trunking
Topic Summary: Size of earthing conductor
Created On: 09 July 2013 09:46 PM
Status: Post and Reply
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 09 July 2013 09:46 PM
User is offline View Users Profile Print this message



primo

Posts: 439
Joined: 10 January 2008

Installing some lighting trunking that isn't continuous back to the board. Te trunking will be be fed in FP and then singles run inside the trunking to each fitting and I want to use the CPC from the FP to earth the trunking.
I think this should be okay. I've had a look through GN8 but couldn't see anything regarding minimum size of earthing conductor for trunking so I'm assuming that it should match the largest size of earthing conductor required for any circuit in the trunking?
 09 July 2013 10:28 PM
User is offline View Users Profile Print this message



AJJewsbury

Posts: 11553
Joined: 13 August 2003

so I'm assuming that it should match the largest size of earthing conductor required for any circuit in the trunking?

Correct (there a reg somewhere in section 54 to that effect - common c.p.c.s) (technically not termed an an 'earthing conductor' though - that connects the installation to the means of earth).
- Andy.
 10 July 2013 08:36 AM
User is offline View Users Profile Print this message


Avatar for Parsley.
Parsley

Posts: 1039
Joined: 04 November 2004

543.1.2

"Where a protective conductor is common to two or more circuits, its cross-sectional area shall be: (i) calculated in accordance with Regulation 543.1.3 for the most onerous of the values of fault current and
operating time encountered in each of the various circuits, or
(ii) selected in accordance with Regulation 543.1.4 so as to correspond to the cross-sectional area of the largest line conductor of the circuits."


Regards
 10 July 2013 09:39 AM
User is offline View Users Profile Print this message



AJJewsbury

Posts: 11553
Joined: 13 August 2003

That's the one - thanks Parsley!
- Andy.
 10 July 2013 12:21 PM
User is offline View Users Profile Print this message



primo

Posts: 439
Joined: 10 January 2008

Tanks
Statistics

See Also:



FuseTalk Standard Edition v3.2 - © 1999-2014 FuseTalk Inc. All rights reserved.