The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
failed home inspection.
by HotLine1
01/19/17 01:41 PM
Safety at heights?
by Trumpy
01/19/17 05:25 AM
Old Bath Fan
by gfretwell
01/19/17 01:38 AM
Search Function
by Webmaster
01/18/17 11:13 PM
Forum Software Upgrade coming soon...
by Webmaster
01/18/17 09:17 PM
New in the Gallery:
Desk-mounted "power-board"
Top Posters (30 Days)
Webmaster 30
HotLine1 21
Ruben Rocha 16
Trumpy 13
gfretwell 13
Who's Online
1 registered (Ruben Rocha), 0 Guests and 197 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#138328 - 08/28/03 05:37 AM Multiple Earth Breaks in Lead
Dapo Offline
Member

Registered: 03/04/03
Posts: 52
Loc: Australia
I have been handed a lead to have a look at, it was cut into three pieces, I was astounded to find that each of the pieces had no earth continuity. the active and neutral conductors tested ok. I could not get a reading on the earth even with an insulation test.
The lead did not have any obvious kinks or damage and looked reasonably new.
The pieces of the lead were each about three to four metres in length.

I cut one of the pieces in half and tested again this time one piece had continuity, I stripped the other piece, The earth conductor felt to be broken in one place (easily kinked). The conductor did not look to be damaged in any other way.

I don't know how leads are manufactured, But my thought is during manufacture, the tension may have been set to high on what ever type machine rolls the earth cable.

Does anyone have any theories on this?

Regards Graham

Top
Test Equipment:

Large Selection of Test Equipment For Electrical, HVAC, Test & Measurement
Large Selection of Test Equipment For Electrical, HVAC, Test & Measurement

#138329 - 08/28/03 06:55 AM Re: Multiple Earth Breaks in Lead
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2349
Loc: Vienna, Austria
I once read a post about German NYM cable (non-metallic solid core cable used for in-wall wiring) that said there was a break in the conductor and the factory just wrapped it with a copper foil that was much thinner than the wire. Naturally it first worked, but under load the foil served as a fuse.

Top
#138330 - 08/28/03 10:04 PM Re: Multiple Earth Breaks in Lead
Trumpy Offline


Member

Registered: 07/05/02
Posts: 8553
Loc: SI,New Zealand
Gray,
I would say that this sounds a bit peculiar and a bit dangerous too!.
I would agree with you saying that it could have happened at the factory.
I've been on a tour through a cable factory and the flexes are made by spraying the plastic on to the pre-twisted insulated cores.
I'd say it is a tensioning problem, during manufacture.
I wonder how many more people have flexes like the pieces you have?.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

Top


ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals