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Re: quickie elect. question

To: Trevor Boicey <tboicey@brit.ca>
Subject: Re: quickie elect. question
From: "Timothy R. Hoerning" <hoerni@cooper.edu>
Date: Fri, 29 Apr 2005 16:51:36 -0400 (EDT)
On Fri, 29 Apr 2005, Mike Rambour wrote:

>
>   I would not know BX from BS so let me describe it differently...it
looks
> like 2 wire romex but its kind of a fabric covering, NOT on the wires
> themselves that is normal vinyl just the sleeve that holds them
> together.  Its only 2 wires at the breaker box also, no ground anywhere.
I
> have also put in some 3 prongs with only 2 wires a few times but that is
> not legal and not safe either since you assume you have a valid ground
when
> you see 3 prong plugs.

        Sorry if I misled you but I connect all three wires.  The Hot and
Neutral as usual and the third prong to the bare wire inside the armor
(which I said before was the ground - There actually is a third wire not
just the shield).  The outlet checker lights correct and I'm not making any
other connections.


on Fri, 29 Apr 2005, Trevor Boicey wrote:

> Timothy R. Hoerning wrote:
>    ...but I'd be very curious to see if any application allowed the use 
> of the BX shield as a ground. (and a bit surprised I guess... it sounds 
> very wrong to me)
> 
>    BX wire is normally to be used as "armoured wire", where it will be 
> exposed to possible damage. Such as in a garage where a length will have 
> to go down a wall exposed, or to a wired-in machine like a permanent air 
> compressor where the cable is exposed from a junction box into the unit.
> 
>    The metal shield is designed to protect from piercing, say if 
> somebody leans a ladder against it, or hits it with a tool, or similar. 
> By code, certain places require it for this reason.

        Usually you can also run Romex in a conduit in that case too.  Not sure
which is more of a pain.

>    But any BX I've ever installed has a normal ground in the bundle.
> 

        Okay, now that I think about it there is a bare wire inside the armor
that I connect to the plug.  Is that what you are talking about or are you
talking about a third vinyl covered wire?   The bare wire is much small
than the other two and is  in contact with the shield, so I usually consider it
connect to the shield, although in actuallality it could be just the bare
wire that does it.

>    Personally I hate working with the stuff, the little insulating plugs 
> that have to be jammed into the end to stop chafing are just way too 
> hard to get in and never leave me feeling very happy that they are in right.

        To be honest I'm not sure about the chafing plugs.  Non of the outlets
had those when I opened them up.  Of course the house was build in 1928 and
codes do change...


                Tim
<>---------------------------------------------------------------------<>
Tim Hoerning  /  hoerni@cooper.edu
'91 Honda VFR 750, '84 Honda VT500 Ascot, '73 Honda CB350G Super Sport
'87 Chevy El Camino,  '90 Plymouth Laser
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