Ground cable question

Since the DIY forum in area 51 is in the private beta stage, i think this is the site to ask this question, a very easy one.

I've this adapter

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And let's just say that I can't screw the outlet screw through the adapter metal ground hole.

What I did was connect cable to the adapter metal ground hole and connected the other end of the cable to a metal plate that is screwed to a concrete wall.

Is that ok? i don't get any shock or wiring warnings that i did get before without the ground cable.

Ben

Posted 2010-07-26T00:29:15.663

Reputation: 312

1Wait the week to ask at the beta. – random – 2010-07-26T04:03:46.643

It's not a matter of "easy", it's a matter of "topic". Questions on Super User should be about computer software or hardware. – Gnoupi – 2010-07-26T05:59:55.723

Answers

If the metal plate, "screwed into a concrete wall", is not grounded, you have accomplished nothing.

I'm assuming that you currently have a 2-wire, ungrounded outlet. The best solution is to install a GFCI (Ground Fault Current Interrupter) and mark the receptacle with the words "No Equipment Ground". This should be done by a licensed electrician.

Mao

Posted 2010-07-26T00:29:15.663

Reputation: 157

But with the adapter connected to the metal plate the electric protector doesn't show any wiring warning, neither the electric devices connected to it give me shocks, like they would if I remove the adapter-plate cable connection. – Ben – 2010-07-26T01:24:35.167

Ben, have a GFCI installed. No more thinking needed. If you need a ground, you don't have one with a two wire ungrounded outlet, period. You just have a neutral which is impacted by other loads. For personal protection, a GFCI is your only viable option. – Mao – 2010-07-26T20:48:55.360

Ground has to go to ground, I believe. That adepter is only good if the centre screw in your outlet is grounded. I don't know if concrete is a conductor.

Xavierjazz

Posted 2010-07-26T00:29:15.663

Reputation: 7 993

Concrete is not a conductor, but there's a good chance the metal plate he attached to on the wall is itself grounded. – Joel Coehoorn – 2010-07-26T00:49:06.043

@Joel, would you consider it is grounded if when the adapter is connected to the metal plate the electric protector doesn't show any wiring warning, neither the electric devices connected to it give me shocks, like they would if I remove the adapter-plate cable connection?. – Ben – 2010-07-26T01:27:00.297

@Ben - you can't be sure. If the metal plate is large enough it may have be able to accept enough electrons to fool your simple wiring tester, but won't really ground your outlet over time. But typically metal items attached to a non-conductive wall will themselves be grounded, so look around to see if there's any other metal going from plate towards the ground or elsewhere. – Joel Coehoorn – 2010-07-26T02:30:51.537