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

Page 1 of 5 1 2 3 4 5 >
Topic Options
Rate This Topic
#198093 - 01/12/11 10:16 AM knob and tube wiring
evad73 Offline
Member
Registered: 10/23/09
Posts: 10
Loc: minnesota,USA
Knob and tube wiring is common in our area. Ideal used to make a contact pocket voltage tester (61-050), it is no longer available. I used it to identify the hot conductor.
Does anyone know of another method to find the hot conductor?
Top
Work Gear for Electricians and the Trades
#198095 - 01/12/11 11:19 AM Re: knob and tube wiring [Re: evad73]
electure Offline


Member
Registered: 12/24/00
Posts: 4259
Loc: Fullerton, CA USA
evad 73....

If you have a non-contact type voltage tester it would be a cinch to check which conductor is "hot" on K&T.



Top
#198096 - 01/12/11 11:56 AM Re: knob and tube wiring [Re: electure]
Bill Addiss Offline
Member
Registered: 10/07/00
Posts: 3875
Loc: NY, USA
Originally Posted By electure
evad 73....

If you have a non-contact type voltage tester it would be a cinch to check which conductor is "hot" on K&T.




iagree Top of my must-have tool list.

Bill
Top
#198110 - 01/12/11 07:04 PM Re: knob and tube wiring [Re: Bill Addiss]
HotLine1 Offline


Member
Registered: 04/03/02
Posts: 6776
Loc: Brick, NJ USA
evad:

Showing my age now...long before the 'non-contact' age, internet, cell phones, cordless landlines, and a whole lot of stuff........

Locate a 'ground' somewhere within the building, or if that's not possible, a known neutral point. even if you have to go back to the service entrance. Connect a suitable length of #12 stranded THHN or equal to said point & stretch it out to the location you want to test. You then have to skin a test point on the K&T conductors and use whatever tester (wiggy, digital, etc).

I did not say it was easy or quick; but it works. If I had to do it today, I'd pull out the non-contact, I have an Ideal, Gardner Bender & a TIF. Any of those are available thru WWGrainger, most electrical supply houses and the big boxes. Look in Tools for Electricians in the right hand border ads right here also, you may find one.

_________________________
John
Top
#198129 - 01/13/11 04:32 AM Re: knob and tube wiring [Re: HotLine1]
sparky Offline
Member
Registered: 10/18/00
Posts: 5303
what HotOne said

with one aside...

i have an office cha cha K&T meter, (one of these)>>>>


around here that #12 might need to be run closer to the nuke plant....


~S~
Top
#198135 - 01/13/11 07:28 AM Re: knob and tube wiring [Re: sparky]
HotLine1 Offline


Member
Registered: 04/03/02
Posts: 6776
Loc: Brick, NJ USA
A reminder of days gone by!!! LOL; LMAO
_________________________
John
Top
#198143 - 01/13/11 12:01 PM Re: knob and tube wiring [Re: HotLine1]
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9039
Loc: Estero,Fl,usa
Back in the olden days we used neon testers. They could give you some bad indications but I am not sure a ticker is really any more reliable. I still would not stake my life on either of them. They are just indicators, not testers (to steal the language of U/L)
_________________________
Greg Fretwell
Top
#198150 - 01/13/11 12:57 PM Re: knob and tube wiring [Re: gfretwell]
HotLine1 Offline


Member
Registered: 04/03/02
Posts: 6776
Loc: Brick, NJ USA
Greg:
Are you talking about the neon 'tube' with two leads? If so, how did you do that?

_________________________
John
Top
#198151 - 01/13/11 01:18 PM Re: knob and tube wiring [Re: HotLine1]
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9039
Loc: Estero,Fl,usa
You never saw the neon tester pen? They typically have a small screwdriver on one end and a pocket clip. The clip is the "ground" and you are the ground electrode system, capacitively coupled to the earth. There is a megohm resistor there so you won't see circuit current. If you touch the screwdriver to a hot lead, the neon lights. Sometimes you just have to be close to the hot lead. They may not light 100% of the time, particularly if you are very well isolated from ground, like up in an attic on dry truss chords but they usually work OK.

I will root around and see if I can come up with one.
_________________________
Greg Fretwell
Top
#198155 - 01/13/11 03:59 PM Re: knob and tube wiring [Re: gfretwell]
mikesh Offline
Member
Registered: 06/07/06
Posts: 613
Loc: Victoria, BC, Canada
Non contact volt testers can give neutrals a hot indication where part of a circuit is chopped out and the return is through a load as a result of a bad assumption. When it comes to K&T I treat all the wires as hot until I am the one that cut it and I am not perfect so be careful the neutrals can be very dangerous too.
Top
Page 1 of 5 1 2 3 4 5 >

Member Spotlight
Member Since: 02/23/13
Posts: 204
New in the Gallery:
SE cable question
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box


Who's Online
0 registered (), 93 Guests and 11 Spiders online.
Key: Admin, Global Mod, Mod
 
New in the Gallery:
SE cable question
 
Top Posters (30 Days)
Admin 47
HotLine1 43
gfretwell 19
Ruben Rocha 12
Trumpy 9
 
Newest Members
Freecrowder, clee512, Jdscott2005, FAIZAN, Regitest2

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