Re: How to ground electric outlets over a slab?

On Apr 29, 8:04 am, "John Grabowski" <jgrabo...@xxxxxxxxxxxxx> wrote:
"Nate Nagel" <njna...@xxxxxxxxxxxx> wrote in message

news:gt80b001rld@xxxxxxxxxxxxxxxxxxxx





<RJ> wrote:
On Mon, 27 Apr 2009 19:21:30 -0700, Jonathan Sachs
<081...@xxxxxxxxxxx> wrote:

I used to own a house that was built on a stemwall foundation. I
grounded the electric outlets by drilling a hole up through the bottom
plate under each outlet box, pushing ground wires up through the hole,
and fishing them into the box.

I'm now buying a house that is built on a slab, and many of the
outlets are ungrounded. How should I deal with the problem in this
case?

How many appliances require a grounded ( 3 pin ) outlet ?
In my house, that woiuld be the washing machine, and the fridge.
As far as I know, all other plug-ins use a ( 2-pin ) polarized plug.

So, unless your community requires 3-hole sockets, why bother ?
Just be sure that the wide slot is "neutral".

In my case, we have awful power, so I have two UPSes and tons of surge
suppressors.  If the worst should happen, the "protected equipment
warranty" is void unless the UPS or surge suppressor is connected to a
grounded outlet.

This may sound like a far-fetched scenario for many people, but a whole
mess of people in my neighborhood lost a lot of electronics a year or so
ago when there was an "incident."  Even with my "massive overkill"
approach to surge protection, I lost a circuit board in my air filter (at
that time not protected; now it is) a circuit board in my dishwasher (only
protected by the main panel surge suppressor because it's hardwired) and a
really old surge strip.  Dominion Power denied any responsibility; I
repaired all the equipment myself so the cash outlay was below what our
homeowner's deductable would have been.  (lost receipt for the main surge
suppressor breaker)

*Nate, make sure that you have a good grounding system for your home. A
water pipe ground and ground rods should help with your problem- Hide quoted text -

It appears to be OK although I have not investigated thoroughly (how
would one test something concealed like ground rods anyway?) but
everything inside the house looks copacetic. What apparently happened
was that a tree fell on a high voltage power line which fell on top of
a lower voltage power line thus momentarily producing a voltage 10x or
more normal. With what should have been an odd failure, I feel lucky
to get away as easy as I did.

But that prompts a question - short of going outside and digging along
the ground cable and inspecting the number of buried ground rods, how
would one determine if an older house does in fact have proper
grounding? (I know, lift the neutral to the pole and see if anything
blows up...)

Actually you just reminded me that we just replaced our fridge which
WAS an old, purely mechanical device with a fancy new one with an
electronic control/display.... probably should slap a point of use
surge protector on that as well.

nate
.

Relevant Pages

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  • Re: http://h71000.www7.hp.com/?
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  • Re: Power Conditioners Worth the Money?
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