Trying to convert 2 prong to 3 prong outlets (BX wiring)
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Trying to convert 2 prong to 3 prong outlets (BX wiring)
My house was built around 1957 and I have the old 2 prong outlets. My wiring is BX.
I thought BX was supposed to ground itself back to the panel but when I use a circuit tester it indicates open ground. I plug the 3 prong circuit tester into an adapter while testing. The confusing thing is that if I connect the adapter wire to the center screw in the outlet then plug the tester into the adapter I get a solid ground indication. I need to have solid grounding for my computer equipment and my entertainment equipment so I currently use the adapter method but it makes access to the other outlet plug extremely awkward and impossible for another adapter arrangement below it. If the adapter wire gives true ground indication on both my tester and my suppressors can I assume that I can simply pigtail a ground from my new 3 prong outlet to the metal outlet box?
I thought BX was supposed to ground itself back to the panel but when I use a circuit tester it indicates open ground. I plug the 3 prong circuit tester into an adapter while testing. The confusing thing is that if I connect the adapter wire to the center screw in the outlet then plug the tester into the adapter I get a solid ground indication. I need to have solid grounding for my computer equipment and my entertainment equipment so I currently use the adapter method but it makes access to the other outlet plug extremely awkward and impossible for another adapter arrangement below it. If the adapter wire gives true ground indication on both my tester and my suppressors can I assume that I can simply pigtail a ground from my new 3 prong outlet to the metal outlet box?

#2
I need to have solid grounding for my computer equipment and my entertainment equipment
If the adapter wire gives true ground indication on both my tester and my suppressors can I assume
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I can say I have first hand knowledge that this can happen. Bad BX running under my house in a crawlspace caused a fire. This is exactly what the investigator said, that the insulation degraded causing a short to the armor, and it glowed hot enough to ignite the floor joists without tripping the breaker. In order to get a new certificate of occupancy the house had to be completely rewired and all BX removed.
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So I gather that you are saying the GFCI is sensitive enough to detect a voltage change due to a short while the breaker is unable to detect the voltage change. Is there any way I could use GFCI and ground my equipment directly somewhere other that back to the box (which would cost me quite a bit since the room in question is over a garage under the house and I dont think I can snake through). I dont think I saw a breaker bar at the box could I be missing something? It is breakers by the way and looks fairly recent. I moved into the house due to a family members passing so I dont have a solid history on what was done when.
#6
ground my equipment directly somewhere other that back to the box
(which would cost me quite a bit since the room in question is over a garage under the house and I dont think I can snake through).
I dont think I saw a breaker bar at the box could I be missing something?
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The other thing with older BX cables when you try to change the junction box there is a golden rules with them you CAN NOT use plastique boxes with bx cable due you loose the bonding { grounding } very easy and if you have to use the plastique box then you will have to get a bonding lockring to bond it together. { that is one of very few legit way to deal with old school BX's }
But normally just run new MC { Metal Clad } they will have it own grounding conductor and you will not have to worry about the BX bonding/grounding issue.
Merci,
Marc
But normally just run new MC { Metal Clad } they will have it own grounding conductor and you will not have to worry about the BX bonding/grounding issue.
Merci,
Marc