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Grounding a non grounded outlet....cold water pipes?

T

Tim Marcus

Jan 1, 1970
0
I have recently moved my electronics bench into my new place. However,
there are only 2 prong outlets in the entire apartment (save the
bathroom and kitchen) I would like to ground the outlet that the bench
is powered off of, so that I might aviod the safety hazards of
repairing on an bench with the ground lifted. I was told that I might
be able to ground to a copper cold water pipe (under the kitchen
sink). Has anyone heard of this before? Just want to run this by the
experts before I run the wires. Thanks - Tim
 
C

CJT

Jan 1, 1970
0
Tim said:
I have recently moved my electronics bench into my new place. However,
there are only 2 prong outlets in the entire apartment (save the
bathroom and kitchen) I would like to ground the outlet that the bench
is powered off of, so that I might aviod the safety hazards of
repairing on an bench with the ground lifted. I was told that I might
be able to ground to a copper cold water pipe (under the kitchen
sink). Has anyone heard of this before? Just want to run this by the
experts before I run the wires. Thanks - Tim

I wouldn't do that. If you have a fault, and if there's a section
of plastic pipe (as there often is), you could endanger somebody in
the kitchen.

There are codes governing how this should be done.
 
A

Alex Bird

Jan 1, 1970
0
F**k, in the UK that would mean you had 1920's wiring. Re-wire?

You have sockets/outlets in the bathroom? Really?

Sorry, not very helpfull,
Alex
 
W

w_tom

Jan 1, 1970
0
Never dump electricity into any pipe. The only wire that
connects to pipes exists to remove electricity. Even kitchen
does not have three prong outlets? Move. Or at minimum,
install GFCIs with the associated 3 word warning label about
no ground available - as specifically listed in the National
Electrical Code book. Never use pipes as a safety ground.
 
J

Jamie

Jan 1, 1970
0
I would reconsider living there.
i wouldn't be surprised if peg wire is still in use for some area's
and don't use the utility plumbing to ground your bench, i wouldn't want
to be the one sitting on the porcelain goddess while your charging up the
pipes. ;)
try running your own ground from outside .
 
A

Aries Quitex

Jan 1, 1970
0
Tim said:
I have recently moved my electronics bench into my new place. However,
there are only 2 prong outlets in the entire apartment (save the
bathroom and kitchen) I would like to ground the outlet that the bench
is powered off of, so that I might aviod the safety hazards of
repairing on an bench with the ground lifted. I was told that I might
be able to ground to a copper cold water pipe (under the kitchen
sink). Has anyone heard of this before? Just want to run this by the
experts before I run the wires. Thanks - Tim

German Solution: Get yourself a 3ft iron-rod, hammer it into the ground
outside and then run separate groundingwires to every outlet.

I would suggest you have a look into your breakbox/wiringbox/howevercalled
and see if it is earthed and if there is a FI (Fast Interrupt) switch
installed. A 3-wire power-line-system could becme a live-saver quite fast.
 
A

Alex Bird

Jan 1, 1970
0
Jamie said:
i wouldn't be surprised if peg wire is still in use for some area's

What's that? (I have a mental image of wooden conduit with wires
fixed between pegs inside)

I have discovered some original lead wiring, abandoned thankfully, in
my floor. It has a lead jacket with copper conductors in an old
fashioned rubbery plastic I can't remember the name of. Supposedly it
becomes brittle exposed to air, but the piece I saw was actually in
perfect condition. Still glad it's disconnected though.

Alex
 
T

Tim Marcus

Jan 1, 1970
0
OK - I guess I can conclude that the pipe thing is a bad idea. Moving
in not an option right now. I could put the ground stake in the ground
- but this is northern Vermont - the ground will be frozen solid for 4
more months! I guess I can run a long extension cord to the 3 prong
outlet in the kitchen - but who knows where that is grounded to? I
agree - the wiring in this apartment needs an update big time - Thanks
- Tim
 
R

Rick

Jan 1, 1970
0
Just because an outlet has 3-prongs doesn't mean it's grounded.
You'll need to take it out and look for a ground wire before you
know for sure.

Typically buildings either have grounded outlets or they don't,
and someone might have installed 3-prong outlets in the kitchen
and bathroom just to avoid having to use 3-to-2 adapters.

Rick
 
K

Ken Weitzel

Jan 1, 1970
0
Hi...

I'm really glad you said that...

I 'm thinking even more likely than needing an
adapter would be a case where an outlet simply
needs replacing?

Dunno about the rest of the world, but here in
Canada I doubt I could find an ungrounded socket
if I wanted one.

So - it's quite likely someone would simply buy
a three prong and leave the ground terminal vacant.

Scary scary stuff :(

Take care.

Ken
 
S

Sam Goldwasser

Jan 1, 1970
0
Rick said:
Just because an outlet has 3-prongs doesn't mean it's grounded.
You'll need to take it out and look for a ground wire before you
know for sure.

Typically buildings either have grounded outlets or they don't,
and someone might have installed 3-prong outlets in the kitchen
and bathroom just to avoid having to use 3-to-2 adapters.

Not necessarily. Check them. Often, selected outlets are newer and
properly grounded. Added for room A/Cs, a new fridge, microwave, etc.

But as noted, others can indeed have 3 prong outlets and not be grounded.

In fact, it's hard to find a 2 prong duplex outlet at a hardware store!

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
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T

Tim Marcus

Jan 1, 1970
0
I think the outlets that are 3 pronged are internally grounded - or
ground fault protected or something. They were installed to keep the
place up to code - the question is, do I want to ground to those
outlets? Or do I want to run a seperate ground somewhere for my
workbench?
 
D

Dbowey

Jan 1, 1970
0
Tim posted:
I think the outlets that are 3 pronged are internally grounded - or
ground fault protected or something. They were installed to keep the
place up to code - the question is, do I want to ground to those
outlets? Or do I want to run a seperate ground somewhere for my
workbench?

No such thing as internally grounded. For a 3 contact receptacle, the round
(centered) pin is the safety ground (green), and it is to be grounded back to
the ground bar in the breaker/fuse panel. The bare wire in a "2-wire with
ground" cable is used for this purpose.

The white wire, connected to the silver-colored contact of the receptacle, also
is connected back to ground in the breaker/fuse panel. In the US I'm sure it
is not appropriate to put a jumper at the receptacle, to connect the safety
ground (green) to the white wire. In my opinion that would not be safe.

To be safe, all grounds should be connected at the same location; that is, at
the breaker/fuse panel. A GFCI, if you use one, works by seeing a voltage on
the ground wire that exceeds the voltage on the neutral wire. It can't do this
if the grounds are incorrect.

To do this right, run a 2-wire with ground cable, from the bench to the
breaker/fuse panel and add a circuit for it in the panel. If 15A is enough
current for the bench, you can use #14 wire, for 20A use #12.

For safety's sake, check at the 3 wire receptacles and the distribution box to
see that they are properly wired. If the 3-wire receptacles DON'T have a
proper ground, repost here and I or someone else will post the Chapter and
Verse of what is being violated so you can tell the landlord to fix it.

Don
 
S

Sam Goldwasser

Jan 1, 1970
0
[email protected] (Dbowey) writes:

To be safe, all grounds should be connected at the same location; that is, at
the breaker/fuse panel. A GFCI, if you use one, works by seeing a voltage on
the ground wire that exceeds the voltage on the neutral wire. It can't do
this if the grounds are incorrect.

Not really. A GFCI compares the current on the Hot wire with the
current on the Neutral wire. If there is a difference that exceeds
some magic number (something like 8 mA), it trips. A GFCI does NOT
need an Earth ground to function. In fact, the ground hole of the
GFCI is not attached to ANYTHING inside it.

More info at:

http://www.codecheck.com/gfci_principal.htm#top

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: The email address in this message header may no longer work. To
contact me, please use the feedback form on the S.E.R FAQ Web sites.
 
W

w_tom

Jan 1, 1970
0
You cannot make those many assumptions. Work first from
well understood facts. No receptacle is internally grounded.
A safety ground wire must connect to receptacle's 'third
prong' connecting screw to breaker box ground. Otherwise
receptacle is not safety grounded.

Do not connect third prong to a ground rod. Earth rod is
not safety ground. That third prong must have a dedicated
wire that connects directly back to breaker box ground bus.
No way around that requirement. Outlet ground is safety
ground - not earth ground. Receptacle safety ground must
connect to breaker box ground bus - and not via other
conductors such as pipe.

Not possible to make that ground connection? Then you need
an electrician - who comes with fancy toys and techniques to
always make that ground connection. Just anther reason why
you pay him the big bucks.

As stated previously, your only other alternative for human
safety is a GFCI. Do not connect that third prong to its own
earth ground rod. Do not connect that third prong to pipes.
Code is quite simply about what is required. Electricians
makes what appears complex instead simple.
 
J

Jim Adney

Jan 1, 1970
0
In fact, the ground hole of the
GFCI is not attached to ANYTHING inside it.

Huh? Are you sure?

I get the impression from this writeup (which you wrote) that the
ground contact of a GFCI SHOULD be connected to ground.

Oh, on second reading, maybe you just meant that the ground contact
just has no connection to any of the GFCI circuitry. In that case,
I'll agree with you, and just chide you for poor wording. ;-)

-
 
T

Tim Marcus

Jan 1, 1970
0
So - what you are telling me to do is use one of the GFCI outlets and
I will be ok, provided that it is grounded to something on the breaker
box in the basement. I have a friend who is an electrician - maybe
he'll cut my landlord a deal.... thanks all - Tim
 
S

Sam Goldwasser

Jan 1, 1970
0
Jim Adney said:
Huh? Are you sure?


I get the impression from this writeup (which you wrote) that the
ground contact of a GFCI SHOULD be connected to ground.

Oh, on second reading, maybe you just meant that the ground contact
just has no connection to any of the GFCI circuitry. In that case,
I'll agree with you, and just chide you for poor wording. ;-)

Right. If there is a Ground wire, the Ground terminal should be
connected to it. However, for normal operation, it doesn't affect
the GFCI. But if a short from Hot to (supposedly grounded case of
an appliance plugged into the GFCI should occur, neither a circuit
breaker or the GFCI will trip. The GFCI will only trip if someone
touches the case of the appliance and a water pipe or grounded surface.

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: The email address in this message header may no longer work. To
contact me, please use the feedback form on the S.E.R FAQ Web sites.
 
R

Robert Blum

Jan 1, 1970
0
Tim posted:

No such thing as internally grounded. For a 3 contact receptacle, the round
(centered) pin is the safety ground (green), and it is to be grounded back to
the ground bar in the breaker/fuse panel. The bare wire in a "2-wire with
ground" cable is used for this purpose.

The white wire, connected to the silver-colored contact of the receptacle, also
is connected back to ground in the breaker/fuse panel. In the US I'm sure it
is not appropriate to put a jumper at the receptacle, to connect the safety
ground (green) to the white wire. In my opinion that would not be safe.

To be safe, all grounds should be connected at the same location; that is, at
the breaker/fuse panel. A GFCI, if you use one, works by seeing a voltage on
the ground wire that exceeds the voltage on the neutral wire. It can't do this
if the grounds are incorrect.

To do this right, run a 2-wire with ground cable, from the bench to the
breaker/fuse panel and add a circuit for it in the panel. If 15A is enough
current for the bench, you can use #14 wire, for 20A use #12.

For safety's sake, check at the 3 wire receptacles and the distribution box to
see that they are properly wired. If the 3-wire receptacles DON'T have a
proper ground, repost here and I or someone else will post the Chapter and
Verse of what is being violated so you can tell the landlord to fix it.

Don

The GFCI does not operate on voltage difference between ground and neutral, it detects a difference in current between hot and neutral. It does not depend on a ground connection.
 
W

w_tom

Jan 1, 1970
0
Your minimal solution and only for reasons of human safety
is a GFCI in that receptacle box or in breaker box circuit for
that outlet. Safety grounding is not relevant as noted in the
previous post:
Or at minimum, install GFCIs with the associated 3 word warning
label about no ground available - as specifically listed in the
National Electrical Code book.

That means grounding, as necessary for some reliable
electronics operations, will not be available. But code does
not care whether appliance does or does not operate reliably.
Code is only concerned with human safety.

How does a GFCI work? From your question, it appears you
still don't understand the good description posted by another
at:
http://www.codecheck.com/gfci_principal.htm#top

If doing electronics work, then understanding how a GFCI
works is as important as understanding how a meter works - and
that simple. Read that www.codecheck.com text again. Since
it is chock full of information, then one reading will not be
sufficient.
 
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