Hi all, never been in this NG before, but I'm hoping someone would be kind
enough to help me out. I am moving into an apartment that has only 2 prong
outlets. My questions are.....
1) I can replace the plugs with 3 holed ones, and install ground wires to
the radiators, which then lead at some point to the main water pipes, so
it'll be grounded. Is there any fire danger associated with this?
2) I have heard of surge protectors that actually have fuses in them which
will trip and break the connection once the influx of power gets to high. Do
these work at all? Also, in this case, would i simply install the new
outlets,m NOT install a ground wire, and let this type of surge protector
handle the extra power in case of a spike or surge? Essentially, does this
type of surge protector REPLACE the requirement for a ground wire?
All in all, I'm concerned about safety for both myself and my equipment. Any
help would be greatly appreciated on this one, thanks all!
Just do not merely replace two hole sockets with three hole ones if you
cannot ground them. I found sockets like that at my son's home. It was the
previous owners low cost electrical upgrade of the home. In a bathroom no
less. Two wire romex was used, so there was no possibility of grounding
until extra conductors were installed.
Upgrades like that are incredibly dangerous. The provide a false sense of
security. It would be better to use GFCIs.
ok i'm just bored and very sleepy here so I'm going to post some
nonsense which you can ignore if you want coz they probably waste your
1) you don't want surges, etc.etc? use a generator which uses an
inverter to output the voltage? Cleaner than mains, no surges,
lightning etc.etc hehehehe.
2) If you want a good ground, connect to your house's metal water
pipes coz that's a very good source to ground to.
3) don't ever ground to gas pipes, they are illegal in most places :)
Grounding to a water pipe to dump electricity is
unacceptable and dangerous. NEC discourages it so many
obvious reasons. The only ground wire to water (or gas) pipes
exists to remove electricity. Never ground to pipes to dump
electricity in those pipes.
How clean is that generator (or UPS) output? Typically not
cleaner than AC mains. But then, who cares? An appliance
already contains internal protection that makes standard
electric 'dirt' irrelevant. The dirt is called 'noise' - not
This UPS, for example, creates 120 VAC by outputting two 200
volt square waves, with an up to 270 volt spike between those
square waves. That is called 'clean' inverter power? Yes,
unfortunately, too many actually believe myths that a plug-in
UPS or generator will always provide cleaner power. Cleanest
power typically comes from utility. UPSes can output dirty
power (in battery backup mode) because electronic appliances
already contain resilient protection; must withstand dirty
electricity without damage.
Appliances already include internal protection. In fact, if
those UPS or power strip surge protector components were
effective, then those $0.10 parts would already be inside that
appliance. So where is the advantage of spending so much
money on power strip and UPS protection? Its called a myth.
To keep so many ill informed, manufacturer must avoid all
mention of important facts such as earth ground. Which kind
of transient does that UPS claim to protect from? A type
typically not destructive. So instead they forget, even in
long pages of specifications (if you can find them), to
mention common (longitudinal) and differential (normal) mode
transients. They simply collect everything under the simple
title of Surge. Therefore the naive will falsely assume all
transients are same.
Did the manufacturer lie? Is it a lie to intentionally
obscure the facts?
A destructive transient is a typically rare event -
occurring about once every 8 years. Those plug-in (power
strip and UPS) protectors quietly forget to mention that they
are not effective for such transients. Better to not mention
earthing to maintain sales.
For those who think a receptacle ground is earth ground; did
you consider wire impedance? Take a 50 foot wire from
receptacle to breaker box. Probably less than 0.2 ohms
resistance. But same wire has maybe 130 ohms impedance from
the perspective of a destructive transient. Let's assume a
plug-in UPS or power strip surge protector is plugged into
that receptacle. A 100 amp transient is connected by that
surge protector from black hot wire to receptacle ground
wire. Will that 100 amp transient transverse 130 ohms
impedance to breaker box? Not likely. Surge protector and
adjacent computer are now at something less than 13,000 volts
relative to earth ground. Where will the transient go?
Through computer and modem to earth ground via phone line.
And so that adjacent plug-in protector has contributed to
damage of computer modem - even when computer is powered off.
Therein lies the problem. Wire has impedance which is why a
receptacle's safety ground is not earth ground. Which is why
the effective protector connects a transient less than 10 feet
to single point earth ground. Now add other factors that only
make a plug-in protector worse. To properly earth a
destructive transient, the wire cannot be spliced, no sharp
bends, and not bundled with other non-ground wires. First two
only increase wire impedance. The latter means that surge
protector only induces transients on other wires - because
transient is bundled with other wires. Again, more reasons
why a plug-in protector is not effective and can even
contribute to damage of the adjacent appliances.
Too many reasons all point to the plug-in protector - power
strip or UPS - as ineffective against destructive transients.
No wonder those components are not already inside the
appliance - that already contains effective protection.
Ineffective protectors are quickly identified - 1) no
dedicated connection to earth ground AND 2) it avoids all
mention of earthing. If they discussed earthing, then you
might discover wire impedance, problems created by sharp bends
and splices, and induced transients. Better to leave
customers ignorant (not mention earthing) so that ill informed
customers will recommend ineffective, overpriced, and
typically undersized plug-in protectors.
Again returning to the bottom line. A surge protector is
only as effective as its earth ground. Being too far from
earthing, the plug-in protectors has all but no earth ground.
No earth ground means no effective protection. If you don't
want surges, then use the less expensive technology proven
effective since before WWII - and not found is grossly
overpriced plug-in solutions. And do not ground to pipes.
Grounding to pipes is unaccptable.
Brian Su wrote:
Check the boxes for ground. You could use an ohm meter from the box to the
water pipe for example. If you read very low then they are grounded/bonded
together. Consult a electrician to be sure. Good grounding is the basis of a
good electrical system. 40+ years ago when 2 wire was installed, there were
very few if any electronics in the home.
If you really are worried about surges then you will need both a service
protector and a point of use protector. The IEEE states that you have to
have 2 out of the 3 protection areas to have protection. ( You do not need
to worry about the distribution class, that is for the utilities protection,
this web page has some good reading, look about to get the best deal. Lots
of manufactures make this equipment.
The circuit breaker protection is way to slow for surge/spikes. Yes they
have a CB in the strip but that is for over load. Read the specs on the
strip. Your looking for something less than 350v let through. Runs in my
mind that mine are like 300v at my computer. The one I installed at the
service is like 700v. Do not get sucked into a 100k warranty for any more
money. You will never be able to prove what happened. So you will never
get the cash.
Secondly you can buy a UPS, expensive, if you get one with voltage and surge
protection included. The cheapy plug in models will not have voltage/surge
I agree that the first thing you should do is check the boxes for a
ground, but not necessarily with an ohmmeter to a water pipe. For a
duplex outlet, loosen the screw that holds the cover plate on. Using
an AC voltmeter (or simple neon test lamp from a hardware store), you
should measure approximately full line voltage (or the lamp will
light) between one of the prongs of the plug and the center screw. In
some cases the head of the center screw might be plastic or coated
with paint. You need to get to the threaded metal part. If you can
take the plate off, an alternative ground test point is the screw in
either metal ear that holds the receptacle to the box.
If you do get this voltage, you can assume that the box is grounded.
Unfortunately, this test doesn't tell you the quality of the ground,
more elaborate testing is required for that. A lot of houses built in
the 50's and early 60's have grounded boxes, but only two wire
ungrounded receptacles. If this is the case for you, the easiest
method is to get a 3 wire receptacle to 2 wire adaptor plug with a
ground wire (or tab) which connects to the center screw.
This would be easier than rewiring the outlet completely with a 3
prong receptacle. I wouldn't do this unless I owned the premises,
could safely shut down the circuit when I was working on it, and knew
a little bit about wiring. Do you fit into that category?
If the wiring is really old, you may not have a ground at all.
Installing a GFCI - Ground Fault Circuit Interupter will give you a
little added bit of safety, but it will not give you a true ground for
you electronic devices.
Neither of those suggestions will indicate whether a ground is good or bad.
Both a voltmeter and a neon lamp will indicate almost full line voltage with
a very high ground resistance, leading to the false conclusion that there is
a "good" equipment ground path. The ohmmeter idea is not perfect, but far
better than your suggestions, and it doesn't require the op to open a box
and expose hazardous voltages.
This isn't a very reliable test at all.
Both a neon test light and a voltmeter will give an apparently good
reading even with a very high resistance ground path. A 100W
incandescent bulb would be a better test, as would the previously
mentioned ohmmeter check to the plumbing.
To be useful, you need a solid, low resistance ground connection.
Bob Weiss N2IXK
You can replace the two prong receptacles with GFCI
receptacles. Adding a three prong receptacle with
a wire to the radiator may or may not provide you
with a safety ground, but that would mean you were
altering the wiring in a building you don't own. I
don't think you want to go there.
You can't establish "ideal" surge protection. That
requires, at a minimum, installing a "whole house"
surge protector at the entry panel, and you don't
have the right to do that. You can get some protection
with point of use surge suppressers, or you could use a
UPS to power your equipment.
A surge protector NEVER replaces the requirement for
a ground wire at the receptacle. The ground is
there for your safety.
Thanks for the reply.....in my research I found this page about GFCI
receptacles at the plug
if you scroll to the bottom it says this...
".....If you're in the situation of wanting to install computer
equipment on two wire groundless circuits take note:
Adding a GFCI outlet to the circuit makes the circuit safe for
you. But it doesn't make it safe for your equipment - you need
a ground to make surge suppressors or line filters effective...."
Now I'm more confused....if i simply replace the plugs and dont ground them,
i can at least plug in my surge protector, but because it isnt grounded, its
useless anyway, to my equipment.....I cant install something ideal at the
panel level.....i can wire to the radiator without necessarily telling my
landlord, which isnt great either BUT at least I could do that then test it
for groundedness, and at least Id know if it was grounded or not...this is
becoming quite a headache.
My very first thought was installing the ground wire in the three prong
receptacle and connecting it to the inside of the small metal box encasing
the entire affair, as I assume that must be grounded.
I hope I dont sound too dull in this matter...lol...its taken me days to
even understand some of the basic terms i seem to keep seeing in my
Yes - it is a headache, but it need not be.
GFCI comes first, for your safety, and has
nothing to do with surge protection. Next
comes a point of use surge protector or
a UPS, because that's all your situation
allows you to do.
That's it in a nutshell, but details are below if
you care to read them.
1) There is a myth that computers MUST be
protected from surges. Not true. Computers will work
fine with or without surge protection.
2) There is a myth that surge protectors are "effective"
where the word "effective" is misunderstood to mean
something like "100% safe from damage". Not true.
A surge can be powerful enough to overwhelm both
whole house and point of use protectors,
Surge protectors are like "crash tested" bumpers on your
car or air bags/seatbelts. Cars run just fine without them.
PC's run just fine without surge protectors. But a car
crash can be violent enough where the safety devices are
overwhelmed. Same is true of surge protectors - a large
enough surge can overwhelm them. A point of use surge
protector, whether grounded or not, provides a little
bit of protection - say roughly analogous to a "crash-tested"
bumper that will withstand a 5 mph impact. A whole house
protector provides much more protection - say roughly
analogous to the air bags/seatbelts.
In your case, the GFCI will protect you. It has nothing
to do with surge protection.
You cannot install whole house protection in your situation,
so that is not an option for you. Any wiring you could do would
also be out of the question, as you do not own the building.
A wire to the radiator connects you to the hot water pipes,
which may or may not be bonded to the cold water pipes.
The effectiveness of that "ground" is questionable, and
becomes more dubious, in terms of surge protection, when
you add in the impedance of the "add-on" wire and connection.
You again have the restriction that you don't own the building.
What does that leave you? You can add a point of use
surge suppresser or a UPS. If the receptacle into which
they plug is grounded, so much the better, but whether
it is or not, that appears to be your only options beyond
installing a GFCI. Those devices provide some protection.
Could you have a surge that would destroy them and the
equipment that plugs into them? Yes. Are they better
than nothing? Yes.
The three prong adapter mentioned in the thread is actually
a bad idea. If the metal box is in fact grounded even
though it has a two-prong receptacle, the adapter still
relies on an uncertain mechanical connection to present
a ground at its ground hole, and can create the false
assumption that a ground is present. Aside from that,
if the box is in fact grounded, it would be better
to install a 3-prong receptacle than an adapter.
Installing a GFCI will bring a ground to the ground hole
on the GFCI **if** the box is grounded and the GFCI is
properly installed. Proper installation includes connecting
a green or bare wire from the GFCI ground screw to the
metal box. The GFCI will still protect you if the metal
box is **not** grounded.
No surge protector, UPS or line conditioner manufacture will honor their
warranty on improperly installed equipment.
I'd bet a pizza those metal boxes are Not grounded, but it's something to hope
If you connect to a radiator, you are also connected to the water line. This
sounds like a good approach, but there might be some drawbacks that I don't
know about (I'm not an electrician). You will need a metal-to-metal
There are adaptors which have a small external terminal for attaching a wire
to the ground prong socket. Where the other end of the wire goes could be a
radiator or a grounding rod outside.
Most surge supressors will have an LED signaling that the connection is
proper. You'll need to check this often, else you could end up unprotected and
not realize it.
Whatever it takes.
1) Recommending a ground to water pipe is bad advise for
multiple reasons as in previous post.
2) LED signaling does not report anything about proper
connection. LEDs may report a missing safety ground or may
report a failed surge protector. Neither can report a good
condition. LEDs can only report a failure condition. And LED
can never indicate the existence of earth ground. No earth
ground means no effective protection. And effective
protection means no damage from direct lightning strikes -
even to the surge protector.
3) A plug-in surge protector adjacent to computer can even
complete a destructive circuit through powered off computer.
That's right. The surge protector can provide a destructive
path from wire with surge to earth ground via computer and
computer modem. A circuit that may not exist if the surge
protector was not adjacent to computer. In the OP's case, two
a) Buy a 'whole house' protector for his landlord to install,
b) plug the largest joule surge protector into the receptacle
(of same phase) closest to breaker box.
In b), at least the protector is closer to earth ground and
farther from computer - to provide some protection. But if a
receptacle does not even have a safety ground, then plug-in
protector only makes damage to adjacent computer easier.
Safety ground is not a replacement for earth ground. No
earth ground means no effective surge protection. Meanwhile
'whole house' protector is typically properly sized so that
surge damage is irrelevant.
In the meantime, what protects that GFCI? Most certainly
not a plug-in protector. Just another reason why the surge
protector (even if using a plug-in type) must be as close to
service entrance, breaker box, and earth ground as is
Surge protection is earth ground. An effective surge
protector only connects a surge to surge protection.
Ineffective surge protectors would have us avoid this entire
conversation. They never mention earth ground because they
don't even claim to protect from the typically destructive
"Michael A. Ball" wrote:
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