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

Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#72229 - 11/21/06 07:50 PM Hot IG
WESTUPLACE Offline
Member
Registered: 03/29/04
Posts: 251
Loc: Kingwood, TX USA
Made a service call. Connect up a large screen TV. Extended the cable (coax) to the sets location. Hooked the cable to the cable box. Pluged in both the TV (3wire cord) and the cable box (2wire cord) I then connected the RCA video & audio cables to the back of the cable box and my helper plugged the rca cables in to the monitor and spark and smoke came out of the cable box. The RCA cable melted. I quickly pulled the plugs. I connected the TV an measured 120v between the cable box (shield) and the TV chassis. Both cable box and TV were plug into a Isolated Ground receptacle. The building was a bank and is now a coffee house. I checked the outlet and found 120v between the ground prong (hole) and the cable shield, and between the ground prong (hole) and the box. I found the breaker controlling the ckt. and turned it off. All voltages gone. Removed the outlet, found it was served by 12/3 bx with BK/WH/RD with the RD connected to the IG ground terminal. Someone had connected this red wire to the hot line in the J box in the ceiling. I removed the hot and installed a propery wired receptacle. The band members has been using this receptacle for their equipment and complained about hum. The fact that all their equipment was electricly hot, it is a wonder someone did not get electrocuted. Always use caution with IG receptacles. Robert
Top
Work Gear for Electricians and the Trades
#72230 - 11/21/06 07:58 PM Re: Hot IG
napervillesoundtech Offline
Member
Registered: 02/28/06
Posts: 144
Loc: Naperville, IL, USA
Unfortunatly. having worked as a commercial sound technician for many years, the FIRST thing many people do when there system hums is yank the grounding pin. Audio signals (TRS & XLR connectors) are usually tied in with the electrical ground of the sound system. This creates a loop, which can cause a hum. The proper way to get rid of a hum is to transformer isolate the audio line, or ground lift the audio line itself. Leave the electrical connection alone. Sorry. This has always been a rant of mine.

As for the outlet in the bank/shop, isolated ground outlets are nice when wired right. Whoever used a red wire as hot should be shot. People like me get sent to the hospital because of stunts like that.

-Ben
Top
#72231 - 11/21/06 08:15 PM Re: Hot IG
SolarPowered Offline
Member
Registered: 07/05/04
Posts: 625
Loc: Palo Alto, CA, USA
Quote:
Whoever used a red wire as hot should be shot.

Red is supposed to be hot. Ground wires are bare, green, or green with one or more yellow stripes.

HCF cable is designed to do what they were trying to do there.

[This message has been edited by SolarPowered (edited 11-21-2006).]
Top
#72232 - 11/22/06 08:28 AM Re: Hot IG
smokumchevy Offline
Member
Registered: 02/14/03
Posts: 60
Loc: Ottawa, Ontario, Canada
It seems to be the way here in Ontario Canada as well to use the red of a 3-wire bx for the ground on a dedicated ground outlet.

I usually candycane tape the red with green tape to let others know of its intention.

So far this is a non issue with our local authority.
Top
#72233 - 11/22/06 02:55 PM Re: Hot IG
hbiss Offline
Member
Registered: 12/16/03
Posts: 886
Loc: Hawthorne, NY USA
I know we talked about reidentifying the red as a ground before. As far as I know there is no problem with that as long as it's reidentified at BOTH ENDS. This was not the case here and apparently someone came along and assumed the red was a hot.

They do make IG MC cable, it has two grounds- one green and the other (IG)yellow/green. You don't need to go as far as HCFC cable.

-Hal

[This message has been edited by hbiss (edited 11-22-2006).]
_________________________
www.myphonetechs.com
Top
#72234 - 11/22/06 03:42 PM Re: Hot IG
Rewired Offline
Member
Registered: 01/01/06
Posts: 558
Loc: Hamilton, Ontario, Canada
Smokeumchevy:
Ya I have seen the red as an IG many times before as well, BUT now if thats the case the inspector will not even pass it if its taped green, you MUST re-identify the red with GREEN heat shrink tubing.

BTW where in Ontario are you? Just wondering as I am in "The Hammer".

A.D
Top
#72235 - 11/22/06 03:55 PM Re: Hot IG
Sandro Offline
Member
Registered: 12/30/01
Posts: 444
Loc: Stoney Creek, ON, Canada
smokumchevy...... check 4-036. Red has not been permitted in the Ontario code for at least the last few years now ever since they started manufacturing the BX cable with the green coloured conductor.

edit : to insert code number




[This message has been edited by Sandro (edited 11-22-2006).]
Top
#72236 - 11/22/06 04:15 PM Re: Hot IG
mikesh Offline
Member
Registered: 06/07/06
Posts: 613
Loc: Victoria, BC, Canada
In Victoria we used to allow the red wire in BX to be taped green for IG outlets. Since ISO bx has become redily available we will no longer permit green tape on a red wire. Red is not a good color for a bonding conductor and this illustrates the reason.
Top
#72237 - 11/22/06 06:52 PM Re: Hot IG
Eddy Current Offline
Member
Registered: 09/26/06
Posts: 111
Loc: Ontario,Canada
Quote: "This was not the case here and apparently someone came along and assumed the red was a hot."


Exactly why we can not just tape it a different colour anymore. And the fact that the right colours are available.

I am also in Ontario GO SENS GO !
Top
#72238 - 11/22/06 07:48 PM Re: Hot IG
hbiss Offline
Member
Registered: 12/16/03
Posts: 886
Loc: Hawthorne, NY USA
Another question that comes to mind is where did the original installer intend to land that IG in the box? It's supposed to go back to the service ground bar. Ground it to the box and you don't have an IG and you are wasting your time with an IG receptacle.

That is if you aren't wasting yout time with an IG anyway...

-Hal
_________________________
www.myphonetechs.com
Top
Page 1 of 2 1 2 >

Member Spotlight
Member Since: 12/24/00
Posts: 4259
New in the Gallery:
SE cable question
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box


Who's Online
0 registered (), 90 Guests and 10 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
Stack, Scotto, Freecrowder, clee512, Jdscott2005

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