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| Author |
Message |
Xerxes409
Guest
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 Posted: Mon Jul 14, 2003 12:24 am Post subject: Power supply causes "Tingling" sensation |
 |
|
Recently I built a new PC with a nice 430 watt TruePower power supply.
While putting the PC together I was horrified to feel a small
"tingling" sensation whenever I touched any metal part on the PC case
-- INCLUDING the metal back of my iPod when it was plugged in through
FireWire.
I plugged my old power supply into the same power strip and felt a
little tingle, but not as much as the new one (it's only 300 watts or
so).
Anyway, it's pretty obvious that this should not be happening, and I
need some advice. The kicker is that I live in Japan in a house that
was built during the 1980s and there are only two-prong outlets (as is
the case all across Japan, actually). The three-prong plug is plugged
into a power strip that has three-prong outlets (BUT only connects to
two-prong).
So my question is: is a grounding problem, a wiring problem inherent
of the house itself, or a power supply problem? (Probably not the
latter, as the same thing happens with another power supply.)
This is freaking me out so much I refuse to turn on the computer or
even plug it in. :/
-dropframetango |
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CJT
Guest
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| Posted: Mon Jul 14, 2003 12:51 am Post subject: Re: Power supply causes "Tingling" sensation |
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|
Xerxes409 wrote:
| Quote: | Recently I built a new PC with a nice 430 watt TruePower power supply.
While putting the PC together I was horrified to feel a small
"tingling" sensation whenever I touched any metal part on the PC case
-- INCLUDING the metal back of my iPod when it was plugged in through
FireWire.
I plugged my old power supply into the same power strip and felt a
little tingle, but not as much as the new one (it's only 300 watts or
so).
Anyway, it's pretty obvious that this should not be happening, and I
need some advice. The kicker is that I live in Japan in a house that
was built during the 1980s and there are only two-prong outlets (as is
the case all across Japan, actually). The three-prong plug is plugged
into a power strip that has three-prong outlets (BUT only connects to
two-prong).
|
There's your answer. The power supply is designed to be used with a
safety ground (i.e. 3 prong outlet).
If the capacitor responsible for the tingle fails, the result can be
lethal.
This might be of interest:
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&q=guitar+%22death+cap%22+-mushroom+-fungus&btnG=Google+Search
| Quote: |
So my question is: is a grounding problem, a wiring problem inherent
of the house itself, or a power supply problem? (Probably not the
latter, as the same thing happens with another power supply.)
This is freaking me out so much I refuse to turn on the computer or
even plug it in. :/
-dropframetango
|
If it were me, I'd probably pick up an isolation transformer. |
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Arno Wagner
Guest
|
| Posted: Mon Jul 14, 2003 1:27 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
In comp.sys.ibm.pc.hardware.systems Xerxes409 <colin_tokyo@hotmail.com> wrote:
| Quote: | Recently I built a new PC with a nice 430 watt TruePower power supply.
While putting the PC together I was horrified to feel a small
"tingling" sensation whenever I touched any metal part on the PC case
-- INCLUDING the metal back of my iPod when it was plugged in through
FireWire.
I plugged my old power supply into the same power strip and felt a
little tingle, but not as much as the new one (it's only 300 watts or
so).
Anyway, it's pretty obvious that this should not be happening, and I
need some advice. The kicker is that I live in Japan in a house that
was built during the 1980s and there are only two-prong outlets (as is
the case all across Japan, actually). The three-prong plug is plugged
into a power strip that has three-prong outlets (BUT only connects to
two-prong).
|
It is quite simple: The PSUs have input filters that put capacitors
between the two power lines and also towards ground. In effect that
gives you have the input voltage on the ground line as long as the
ground line is not connected. You only get a slight tingle, because
these filters are designed to be non-lethal when ground is not
connected. The capacitors act as "AC-resistors" and let only a
small current through.
| Quote: | So my question is: is a grounding problem, a wiring problem inherent
of the house itself, or a power supply problem? (Probably not the
latter, as the same thing happens with another power supply.)
|
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
If you have such a water line you can do an external grounding
to make things safer: Run a wire from the chassis to a water-faucet.
The only propper solution however is to get rid of this dangerous
installation and do a propper 3-wire installation with good grounding
in your house.
| Quote: | This is freaking me out so much I refuse to turn on the computer or
even plug it in. :/
|
Understandable.
Regards,
Arno
--
For email address: lastname AT tik DOT ee DOT ethz DOT ch
GnuPG: ID:1E25338F FP:0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
"The more corrupt the state, the more numerous the laws" - Tacitus |
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Harry Bloomfield
Guest
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| Posted: Mon Jul 14, 2003 3:07 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
In article <427af823.0307130921.16c8f948@posting.google.com>,
colin_tokyo@hotmail.com says...
|Recently I built a new PC with a nice 430 watt TruePower power supply.
|While putting the PC together I was horrified to feel a small
|"tingling" sensation whenever I touched any metal part on the PC case
|-- INCLUDING the metal back of my iPod when it was plugged in through
|FireWire.
|
|I plugged my old power supply into the same power strip and felt a
|little tingle, but not as much as the new one (it's only 300 watts or
|so).
|
|Anyway, it's pretty obvious that this should not be happening, and I
|need some advice. The kicker is that I live in Japan in a house that
|was built during the 1980s and there are only two-prong outlets (as is
|the case all across Japan, actually). The three-prong plug is plugged
|into a power strip that has three-prong outlets (BUT only connects to
|two-prong).
|
|
The tingling sensation indicates you are receiving a small shock from
the metalwork. PC power supplies usually have a filter which allows some
leakage of current from the live to the earth or ground connection. As
the case is not grounded, the current will try to pass through you to
ground.
I don't know your local regulations, so all I can suggest is that you
contact a local expert. Certainly here in the UK it would be against the
regulations to provide three pin sockets which did not have a proper
ground fitted.
--
Regards,
Harry (M1BYT)
http://www.ukradioamateur.org |
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Suscom Usenet News
Guest
|
| Posted: Mon Jul 14, 2003 8:07 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
| Quote: | It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
|
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
Check to see if the outlet box is grounded. If so then you can
just use a proper 3 pronged adapter which has a wire that
attaches to the screw in the middle of the outlet.
--
Mark Sokos
Electrical Engineer, Computer Geek (er, programmer),
and no talent bum musician |
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Arno Wagner
Guest
|
| Posted: Mon Jul 14, 2003 11:47 pm Post subject: Re: Power supply causes "Tingling" sensation |
|
|
In comp.sys.ibm.pc.hardware.systems Suscom Usenet News <psychospamhater@yahoo.com> wrote:
| Quote: | "Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
|
O.k., that _is_ a real risk. Unless you ground to the main
pipe directly after it enters the house. That is a legal
installation here technique I have seen several times. Don't
know wheter that also works in Japan...
If you have access to the "ground" you could also get
reasonable grounding by buying the appropriate spike-like,
perhaps 1.5 meters long equipment and hammering it into
the dirt.
Arno
--
For email address: lastname AT tik DOT ee DOT ethz DOT ch
GnuPG: ID:1E25338F FP:0C30 5782 9D93 F785 E79C 0296 797F 6B50 1E25 338F
"The more corrupt the state, the more numerous the laws" - Tacitus |
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ME
Guest
|
| Posted: Tue Jul 15, 2003 12:07 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
"Suscom Usenet News" <psychospamhater@yahoo.com> wrote in message
news:vh47jpk0g8651b@corp.supernews.com...
| Quote: |
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
|
I agree, I live in a farmhouse in the uk and around 20 or so years ago the
lead and copper water pipes were torn out and new "healthier" plastic ones
put in, I still remember mums scream as she got a shock from the cold tap
(just a small shock but as we work with 240 volts in the uk it could have
been lethal), no one had thought about the houses earth was atached to the
water pipe system, to fix it a 6 foot copper spike was driven into a wet
area in the garden and the earth atached to it (turned out the washine
machine was faulty and leaking power through its earth)
Drew |
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Wayne
Guest
|
| Posted: Tue Jul 15, 2003 12:24 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
I have used copper pipes for ground but I suppose there is some risk from a
replaced pipe as mentioned ...
The metal stake into the ground does work but the ground must be moist. One
time when I used to live in the mountains I developed problems with a
washing maching which would not run. When the motor would try to start the
lights in the cabin would get _brighter_! When I told my landlord (a
jack-of-all-trades mountain man) he went outside and started watering the
ground next to the cabin! I thought he was crazy ... until I realized the
problem was fixed. Turns out there was a ground stake there ...
Wayne
"Suscom Usenet News" <psychospamhater@yahoo.com> wrote in message
news:vh47jpk0g8651b@corp.supernews.com...
| Quote: |
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
Check to see if the outlet box is grounded. If so then you can
just use a proper 3 pronged adapter which has a wire that
attaches to the screw in the middle of the outlet.
--
Mark Sokos
Electrical Engineer, Computer Geek (er, programmer),
and no talent bum musician
|
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|
Louis Bybee
Guest
|
| Posted: Tue Jul 15, 2003 12:36 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
"Wayne" <cNhOaSoPtAoMs@qwest.net> wrote in message
news:irDQa.534$gO.75826@news.uswest.net...
| Quote: | I have used copper pipes for ground but I suppose there is some risk from
a
replaced pipe as mentioned ...
The metal stake into the ground does work but the ground must be moist.
One
time when I used to live in the mountains I developed problems with a
washing maching which would not run. When the motor would try to start the
lights in the cabin would get _brighter_! When I told my landlord (a
jack-of-all-trades mountain man) he went outside and started watering the
ground next to the cabin! I thought he was crazy ... until I realized the
problem was fixed. Turns out there was a ground stake there ...
Wayne
|
The problem wasn't fixed by the watering. The symptoms were masked.
The neutral, or one of it's connections, between the source and the panel in
the cabin, was most likely bad. This resulted in current flow in the ground
(bonded to the neutral in the panel), and most likely a semi floating
neutral. Bad - bad - bad!
The issue should have been fixed correctly.
Louis
| Quote: | "Suscom Usenet News" <psychospamhater@yahoo.com> wrote in message
news:vh47jpk0g8651b@corp.supernews.com...
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
Check to see if the outlet box is grounded. If so then you can
just use a proper 3 pronged adapter which has a wire that
attaches to the screw in the middle of the outlet.
--
Mark Sokos
Electrical Engineer, Computer Geek (er, programmer),
and no talent bum musician
|
|
|
| Back to top |
|
|
Harry Conover
Guest
|
| Posted: Tue Jul 15, 2003 3:07 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
"Suscom Usenet News" <psychospamhater@yahoo.com> wrote in message news:<vh47jpk0g8651b@corp.supernews.com>...
| Quote: | "Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
|
Good advise, since in many parts of the US the water service to your
home is provided by non-conductive PVC or HDPE plastic lines. Worse
still, if you do ground to your water pipes, the electrolysis created
can eat through part of the plumbing in your home and a flooded
basement sometimes results (as it did for me).
In my case, we had received "tingles" from touching the cover plates
of outlets and switches. I had determined that the ground plates were
at an elevated potential from ground, but it wasn't untill my daughter
heard the "hiss" of leakign water in the basement that we realized
why. It turned out that the final 6' of 3/4" copper pipe leading to
the water meter has been eroded by electrolysis until it was
paper-thin and starting to develop pinhole leaks. After installing
roughly 80' of new 3/4" copper pipe in the house, and adding a 25'
driven ground the problem vanished.
Never trust the judgement of the contractor that built your house, or
the electrician that wired it. Neither is an EE, and while some of the
craftsmen are more informed than others, not all are aware of the
problems (safety and others) that blind, rote practices like this can
cause.
Still to this day I simply cannot imagine how stupid an electrician is
that can use a water system connected by non-conductive plastic pipe
as a ground system, still it happened in the home I purchased.
Harry C. |
|
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Fix your Windows Problems - FAST.
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Harry Conover
Guest
|
| Posted: Tue Jul 15, 2003 3:18 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
Arno Wagner <me@privacy.net> wrote in message news:<beutr6$8ohm7$2@ID-2964.news.uni-berlin.de>...
| Quote: | In comp.sys.ibm.pc.hardware.systems Suscom Usenet News <psychospamhater@yahoo.com> wrote:
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
O.k., that _is_ a real risk. Unless you ground to the main
pipe directly after it enters the house. That is a legal
installation here technique I have seen several times. Don't
know wheter that also works in Japan...
|
You're assuming that the main pipe is a metalic conductor. Here in
the US it often isn't and, worse still, many of the installing
contractors and electricians simply don't care since it's not
something addressed in the NEC!
| Quote: | If you have access to the "ground" you could also get
reasonable grounding by buying the appropriate spike-like,
perhaps 1.5 meters long equipment and hammering it into
the dirt.
|
Sorry, no! It takes far more than that for a quality ground unless
you are living in a swamp. Say, 25-50 feet in the right kind of moist
soil. That failing, you do what the radio stations do and trench in a
number of radials connected to your ground point.
Harry C. |
|
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|
|
Chris
Guest
|
| Posted: Tue Jul 15, 2003 4:00 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
| Quote: | Never ground to a water pipe. All water pipes must be grounded,
|
Why...not? In fact in many places using a metal water piper as
a grounding electrode is allowed, it is also quite acceptable to use
an adjacent continous (cold water metal pipe as a point to ground
to when converting old 2 prong ungrounded recepticles with grounded
three prong ones when a suitable ground conductor is not availible
or can not be suitably fished -- and when it is not desirable to
simply place a GFI as the first device or overcurrent in that cct.
Generally two placcards are left -- one at the water shut off and
one at each affected service panel to indicate to both electrical
and plumbing contractors in the future that the existing cold water
lines may be used in the electrical grounding and must be maintained
electricaly continuous. Keep in mind this is not something that
would be acceptable in new construction but is allowed in many
places for retro-fit purposes.
| Quote: | Check to see if the outlet box is grounded. If so then you can
just use a proper 3 pronged adapter which has a wire that
attaches to the screw in the middle of the outlet.
|
That scew that attaches to the middle of the outlet -- only secures
the cover plate to the recepticle itself -- it MAY or MAY NOT have
a continous path to ground depending on the make and style of
recepticle.
That aside -- if the box was properly grounded -- with it being an
old two prong style recepticle It is very doubtful that it is -- it
would be just as simple as using a scrap peice of #14 and a new
three prong recepticle -- and a better solution then using the
cover plate screw.
Chris. |
|
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|
|
Louis Bybee
Guest
|
| Posted: Tue Jul 15, 2003 5:24 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
"Harry Conover" <hhc314@yahoo.com> wrote in message
news:7ce4e226.0307141407.36948e79@posting.google.com...
| Quote: | "Suscom Usenet News" <psychospamhater@yahoo.com> wrote in message
news:<vh47jpk0g8651b@corp.supernews.com>...
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
Good advise, since in many parts of the US the water service to your
home is provided by non-conductive PVC or HDPE plastic lines. Worse
still, if you do ground to your water pipes, the electrolysis created
can eat through part of the plumbing in your home and a flooded
basement sometimes results (as it did for me).
In my case, we had received "tingles" from touching the cover plates
of outlets and switches. I had determined that the ground plates were
at an elevated potential from ground, but it wasn't untill my daughter
heard the "hiss" of leakign water in the basement that we realized
why. It turned out that the final 6' of 3/4" copper pipe leading to
the water meter has been eroded by electrolysis until it was
paper-thin and starting to develop pinhole leaks. After installing
roughly 80' of new 3/4" copper pipe in the house, and adding a 25'
driven ground the problem vanished.
Never trust the judgement of the contractor that built your house, or
the electrician that wired it. Neither is an EE, and while some of the
craftsmen are more informed than others, not all are aware of the
problems (safety and others) that blind, rote practices like this can
cause.
Still to this day I simply cannot imagine how stupid an electrician is
that can use a water system connected by non-conductive plastic pipe
as a ground system, still it happened in the home I purchased.
Harry C.
|
I can't comment on the intelligence level of the electrician who wired your
home, but the situation you describe is dictated by the NEC. To paraphrase
the NEC; all piping systems in the dwelling shall be bonded to the main
electrical panel. The water service, if it is metallic would qualify. The
water service, again if it is metallic, and at least ten feet of the pipe is
in contact with the exterior soil, qualifies as one of the required
grounding electrodes. There are additional specifics as to exactly where,
and how, the connection will take place (one reason is to avoid the example
of a plastic section being used for repair setting up a deadly shock
opportunity). The electrician was following a mandate.
While the surface of a ground rod will qualify as the second electrode, the
best option I believe to be a Ufer Ground (a copper conductor in the footing
of your structure) as long as possible. This works in new construction, or a
buried copper wire ring surrounding the dwelling, and brought up to the
service panel.
Louis--
*********************************************
Remove the fish in address to respond |
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|
|
Louis Bybee
Guest
|
| Posted: Tue Jul 15, 2003 5:38 am Post subject: Re: Power supply causes "Tingling" sensation |
|
|
"Harry Conover" <hhc314@yahoo.com> wrote in message
news:7ce4e226.0307141418.d645450@posting.google.com...
| Quote: | Arno Wagner <me@privacy.net> wrote in message
news:<beutr6$8ohm7$2@ID-2964.news.uni-berlin.de>...
In comp.sys.ibm.pc.hardware.systems Suscom Usenet News
psychospamhater@yahoo.com> wrote:
"Arno Wagner" <me@privacy.net> wrote in message
news:besfbv$8mug6$1@ID-2964.news.uni-berlin.de...
It is the grounding. The only way to get rid of this problem is
proper grounding. You can usually get propper grounding from
a water-line. In fact that is how it is obtained in some
houses in Germany: Three phases run to the house and the
zero/ground is connected to the water line within the house.
Never ground to a water pipe. All water pipes must be grounded,
but you shouldn't use a water pipe for a ground. In other words
you want all of your water pipes to be at ground potential for
shock hazard reasons, but you don't want to be using your water
pipes as part of your ground system for the simple reason that
someone could easily come along and replace a section of pipe
with something non-conductive and there goes your ground.
O.k., that _is_ a real risk. Unless you ground to the main
pipe directly after it enters the house. That is a legal
installation here technique I have seen several times. Don't
know wheter that also works in Japan...
You're assuming that the main pipe is a metalic conductor. Here in
the US it often isn't and, worse still, many of the installing
contractors and electricians simply don't care since it's not
something addressed in the NEC!
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The NEC does address the water service, and requires it to be bonded to the
service panel.
| Quote: | If you have access to the "ground" you could also get
reasonable grounding by buying the appropriate spike-like,
perhaps 1.5 meters long equipment and hammering it into
the dirt.
Sorry, no! It takes far more than that for a quality ground unless
you are living in a swamp. Say, 25-50 feet in the right kind of moist
soil. That failing, you do what the radio stations do and trench in a
number of radials connected to your ground point.
Harry C.
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The NEC allows an 8' ground rod to be used as the required supplemental
grounding electrode. In some soils, and moisture levels, the effectiveness
is less than stellar, but it does qualify.
The purpose of radials used by radio stations are related more to acting as
an RF Counterpoise. They can however be a superior grounding electrode, as
they are required to be bonded to the service panel.
Louis |
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larrymoencurly
Guest
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| Posted: Tue Jul 15, 2003 6:51 am Post subject: Re: Power supply causes "Tingling" sensation |
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colin_tokyo@hotmail.com (Xerxes409) wrote in message news:<427af823.0307130921.16c8f948@posting.google.com>...
| Quote: | Recently I built a new PC with a nice 430 watt TruePower power supply.
While putting the PC together I was horrified to feel a small
"tingling" sensation whenever I touched any metal part on the PC case
-- INCLUDING the metal back of my iPod when it was plugged in through
FireWire.
I plugged my old power supply into the same power strip and felt a
little tingle, but not as much as the new one (it's only 300 watts or
so).
Anyway, it's pretty obvious that this should not be happening, and I
need some advice. The kicker is that I live in Japan in a house that
was built during the 1980s and there are only two-prong outlets
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Most PSUs have 5nF RF filter capacitors between the AC lines and the
chassis ground that can cause a tingle, but I think Antec is one of
the few exceptions and has RF filter capacitors only across the AC
lines. The circuit board of my Antec SmartPower is designed with room
for those 5nF capacitors, but it doesn't have any installed.
Shouldn't the lack of line-ground capacitor prevent tingling, assuming
that nothing else is wrong? |
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