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Grounded electric outlet needed for surge protector to work?

by Big Steve / November 14, 2005 9:06 PM PST

I took delivery of a new desktop computer from Velocity Micro last week and would like to move it to another bedroom location. The bedroom where my old PC is currently located happens to have a grounded electrical outlet behind my desk; a grounded electrical outlet which is also wired into a dedicated circuit; nothing else is on the circuit but the computer's grounded electrical outlet. I also have a surge protector connected to that dedicated grounded electrical outlet.

The bedroom where I want to move my new computer to does not have any grounded electrical outlets in it; this house was built back in the early 1960's and the electrical code at that time did not require grounded electrical outlets throughout the entire house; just in the kitchen and bathroom areas; nowhere else.

My question is this; if I decided to set up my new computer in the other bedroom; a bedroom which right now doesn't have any grounded electrical outlets in it; if I connected a surge protector or a back up system to a non-grounded electrical outlet in the other bedroom will my new computer still be protected from power surges or spikes or would I need to hire a
licensed electrician to come out to the house and install a new grounded electrical outlet in the other bedroom and connect the new grounded electrical outlet to it's own dedicated circuit in the new bedroom for the new computer to be fully protected?

Big Steve
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You've heard right.
by R. Proffitt Forum moderator / November 14, 2005 10:40 PM PST

That is not only to protect the equipment, but you.

Your choice here.


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You might check this if you are comfortable
by Steven Haninger / November 14, 2005 11:15 PM PST

There is a good possibility that the box in question is, itself, grounded but the outlets only have 2 prongs. You would have to check this from the center screw on the outlet using a DVM or some continuity testing device. If true, what you may find is the Romex or other wiring used has the ground wire in it already. It's a simple matter of changing the outlet to a grounded type and running a wire from the green lug to the box. You do not usually need a licensed electrician to do this. You do need to turn of the breaker to that outlet. It's also a good thing to check to see if that outlet is properly wired as far as polarity goes. It's an easy task that costs only a couple bucks for the part. Again...if this is within your comfort level. My house was built in the early '50s and all the boxes were grounded but most only had 2 pronged outlets. That's one of the first changes I made myself.

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The not grounded red light is on in the two holes wall outle
by jeff299 / December 6, 2010 5:15 AM PST

The not grounded red light is on in the two holes wall outlet,but is not on in the three holes wall outlet.?
I just bought a Beklin surge protector power strip. It has the surge protector and not grounded light. Now, i have two wall outlets in the same room. One wall outlet has two holes plug in, the other one is three holes plug in. When I plug the surge protector in the two holes wall outlet, the not grounded light is on, when i plug the surge protector in the three holes wall outlet, the not grounded light is not on. So, dose, the two holes and three holes wall outlets make it grounded or not grounded,or it's more than that?

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Blast from the past...
by PKsteven / December 12, 2010 12:35 PM PST

...I posted here almost 6 years ago, lol.

To answer your question, the reason it's saying it's still not grounded, and I may be wrong, but what you will find in many houses, people needed the 3 prong outlets to plug things in as they will still work and an option to snapping off the ground prong on the cord. The bad part? There is likely no actual ground run to that outlet, sort of a cheater's way to get a 3 prong into the wall so the ground is just a dead end and a means to house the ground prong for the cord.

Another way is an adapter from 3 to 2, not a great idea and definitely not safe.

Situations like this don't end well in most cases, if the house was inspected for an earth ground, you would likely not find it.

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Now, What is the Big Deal for a Grounded/earthed wire exist
by jeff299 / December 13, 2010 2:42 AM PST
In reply to: Blast from the past...

Afterall,it just the difference between a two holes and three holes outlet. What is the big deal for a third wire being grounded? Do I need to call an electrican immediately to put a grounded wire and change the two hole outlet into a three holes outlet? presently I did put an adapter from 3 to 2 for my surge protector power strip.

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The Big Deal?
by PKsteven / December 13, 2010 6:08 AM PST

Let's put it this way, if a wire falls off inside oh, say and electric heater with a metal covering. It becomes hot, or live, meaning, if you touch it, you can kill yourself as the ground will be you. Remember, electricity flows through the path of least resistance. You, will be just that.

Now, the 3rd wire, the earth or common ground, provides a path directly back into ground routing it away from you or the electric heater cover. You can still get shocked but you will at least live to tell about it.

Not to mention, and your life is more important but it can definitely do a lot of damage to appliances\computers.

If you rub your foot on the carpet, touch the motherboard, you can fry a PC component, that simple. Now picture your 120 AC current flowing through it or yourself. Even with USB ports, I see people get a shock and fry the port or motherboard, me I discharge before touching any USB device to plug in.

Hopefully this puts it into perspective for you a bit more.


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Grounded electric outlet needed for surge protector to work
by Bob__B / November 15, 2005 5:42 AM PST

I'll say yes.

I take it that where you want to move the machine has a 2-prong socket. (not good)

Maybe a 6-buck work around.
Go to Radio shack/Home depot etc.
Get a 2-prong to 3-prong adapter..has a little wire on the side.
Get a circuit tester..a small thing that when you plug it into the socket will show good/bad..usually by a few lights on the tester.

Plug the adapter into the socket and connect the wire to the screw that holds the cover plate.

Plug the tester into the adapter...if it shows good your good to go.

Suggestion....If you have a house full of 2-prong sockets you might want to fit it into your budget to convert to 3-prong.

When I changed all mine it was amazing the sins I found.

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This depends
by PKsteven / November 15, 2005 6:37 AM PST

For one, if you don't know a lot about it, yes, hire some one, never attempt to replace outlets etc...yourself.
Now, if the house was built that long ago, it doesn't mean it hasn't been upgraded a bit. This depends on how much you know of the history of the house. For safety reasons, don't assume it was.
aluminum wire was used I beleive late 60's early 70's which is known to come loose and become a fire hazzard. Not all homes used it though and was more common in mobile homes. Copper should be installed for better connections and less chance for loosening. You can get surge protectors with 2 prong plug-ins which I still don't recommend. The third prong is called your EARTH GROUND and is meant to create an easier path for current to travel other than your body in case an appliance, etc... is faulty. Now, there are a couple of problems with this>

1. You can get an adapter to fit the two prong and adapt to a three prong surge protector. The problem is, there is still no (earth ground). You can buy one that has an attachment that screws into the screw hole on the metal plate inside on the outlet. The problem is, there may be not common earth ground to the box or outlet. Also, even if you see a ground inside attached to the outlet, it doesn't mean it's not cut off somewhere.

2. Even with a surge protector, if you have no earth ground, current can bypass the surge protector, and many have been known to be faulty, resulting in current flow to the appliance, pc , what have you...

3. Looking into(Ground Fault Circuit Interrupter) GFCI's for outlets are good practice. They cost more but they detect a short to ground and almost instantly disconnect. They were becomming required by code in bathrooms, kitchens , etc.. They are not an answer to an earth ground though.

My suggestion is to call someone if you can afford it. Old wiring is a hazzard to say the least.
Hope this helped, Paul

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by strevino / November 18, 2005 6:40 AM PST
In reply to: This depends

GFCI are not for surge proteccion,, they are for personal body proteccion only..and also needs earth ground ,neutral. and a fase to work ,,please do not confuse the guy.

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by PKsteven / November 18, 2005 2:21 PM PST
In reply to: GFCI..???

<<Looking into(Ground Fault Circuit Interrupter) GFCI's for outlets are good practice. They cost more but they detect a short to ground and almost instantly disconnect. They were becomming required by code in bathrooms, kitchens , etc.. They are not an answer to an earth ground though. >> from original post>>

Read the GFCI's (FOR OUTLETS) I never said surge protector! Oh, so I had a typ-o It should have said ''They are not an answer without an earth ground''

If you want to slam a it right! Of over a hundred posts, I think I am entitled to a typ-o. How many posts do you have? Oh, 2? You are a big help, I can see that lol...

Have a wonderful day, smile!:)

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Ground it!
by W N W / November 17, 2005 9:04 PM PST

In order for the surge protector to work properly, it must be connected to a grounded outlet. The same is true for most all UPS (Uninteruptible Power Source) backup systems. Those for which it is not true, I suggest you avoid. If you are not comfortable installing it yourself, you would do well to spend the bucks on a registered electrician. While he/she is at it, get him/her to install the Ground Fault Protection circuit. I promise you, it is far better to be safe than sorry. Of course, if your house gets hit by lighting or something, all bets are off, but you'll still be better off with a properly grounded (and protected) machine. Hope this helps and good luck!

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Yes, I highly recommend.
by Brianstech / November 18, 2005 3:01 AM PST

With or without a surge protector, your new PC is safest with a hard-wired ground. If your bedroom has carpeting, and especially if you plan on setting your tower on the floor, I believe a good ground is mandatory. Besides safety, it helps to keep the static electricity down, not to mention lint and dust.

I do a lot of wiring on older homes, and sometimes I just add a ground to existing outlets. Maybe yours is not too difficult. Get a book from your library if you'd like to try it yourself.

Whatever you do, remember it is illegal in most states (if not all) to even change an outlet without a permit and inspections. So if you decide to do it yourself, be careful and watch who you tell about it.

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Not Necessarily
by kpennell / November 18, 2005 10:21 PM PST

Surge suppressors contain MOVs (Metal Oxide Varistors; They absorb the surge) from line to ground, neutral to ground, and line to neutral. MOVs don't need a ground path to operate. If you have no ground, the MOVs between line and neutral will absorb the surges coming in. NOTE: Some surge suppressors will not operate without a ground by design but theoretically this is not a requirement. MOVs have a limited life. Many newer surge suppressors are designed to stop working when the MOVs are spent. Certainly it would be a good idea to replace them every 5 years or so. Personally, I would want a grounded outlet for a different reason. If you don't have one, the chassis of your computer may not be grounded and the likelihood of damage from static electricity may be greater.

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Are you sure?
by Corrupt_Data / December 5, 2005 9:30 AM PST
In reply to: Not Necessarily

I've always heard that no matter what type of protection the surge supressor has, it can only function if it has somewhere to dump the surge, IE an earth ground. Without that, the MOV can't simply "absorb" the current, it must pass it to the ground or through the equipment.

It would be nice if it worked as you said though.

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To answer your question directly...
by raiello3 / November 19, 2005 12:44 AM PST

Your computer will NOT be protected from power surges or spikes unless it is connected to a grounded outlet. A surge protector functions by (simple version) absorbing and then shunting the excess current to the grounded line. (Almost) all surge protectors utilize components called MOV's which WILL eventually fail. That's why many of them have a couple of LED's that light up to let you know if 1) the wall plug is grounded and 2) if the surge protection circuit is still functioning. The rare few surge protectors that do not use MOV's are typically "guaranteed" not to fail - but will cost $$$. Of course, if you're operating one of the NASA computers and have the budget..... Your computer should be on its own circuit to reduce the amount of surges (and electrical "noise" which can cause data corruption) commonly generated from sources inside your home. This will also help your surge protector last longer. The other reason to have a grounded receptacle is to prevent static from building up on the computer chassis which can act as a spike all by itself. A surge protector won't help here since the charge originated after the surge protector.
Here are 2 articles that do a good job of explaining Surge Protectors, Uninterruptible Power Supplies, what you should look for and why.
or go to extremetech and do a search for "Surge Suppressors: Anatomy Lesson"

I don't know about other states, but in the state of Michigan, a homeowner is allowed to do any and all residential electrical work on their own home/property. You are still supposed to get a permit and have it inspected to make sure the work was done according to code (read - correctly and safely). In reality, most homeowners I know that have done their own work do not get a permit for small jobs like this due to permit fees and time factors. BUT, if you screw it up, you can get shocked, burn the place down or worse. NO SHORTCUTS! It's either correct or it's WRONG! Just because it works does NOT mean it's correct and safe. This is not rocket science. Common sense and a good book from Home Depot/Lowe's/other hardware supply and/or an experienced and conscientious friend can get you through it without any problems. There are inexpensive circuit testers available at these same stores - get one. Check the plug/circuit for correct polarity, ground and voltage. Edison specs for nominal line voltage at the main panel is 120volts +/- 10%. If the voltage is outside of spec, call Edison. The voltage drop from the main panel to the point of use should be no more than 5% max. But voltage drop for most residential circuits is unusual and should be checked by a professional.

Regarding aluminum wire: First let me say that any installations that were done according to code at the time of installation are grandfathered - meaning it's legal and they can't require you to rip it all out and replace it. However, if your house is wired with aluminum wire, I would recommend you consider replacing it with copper. It won't be cheap but you may get a break on your house insurance and increase the value when you sell. Aluminum wire for "general lighting" circuits has been outlawed for 30 years because of the many house fires it caused. Specifically, the physical characteristics of aluminum allow it to expand and contract significantly more than copper. Because of this, connections can become loose and cause hotspots which can result in a fire. On the other hand, after 30 years, chances are you won't have a problem. Then again, maybe that particular connection may not have had enough of a load to cause a hotspot - yet. Your call. If you decide to leave the aluminum wire as is, you must make sure that any devices or connectors that you use are designed for use with aluminum wire. The device will be stamped "for use with Aluminum wire only", or it may say "AL-CU" meaning that it can be used for either Aluminum or Copper. Do not connect Aluminum and Copper wire together directly. The two dissimilar metals will cause them to chemically react to each other and corrode. You'll end up with another hotspot or if you're lucky, they will just erode away and disconnect from each other. There are devices made which are intended to connect the two without directly touching each other - kinda like a "dielectric union" used to connect galvanized plumbing pipe to copper pipe.

Regarding Ground Fault Circuit Interrupters (GFCI receptacles/circuit breakers). A GFCI is not designed and will not protect equipment. It measures current flow out the hot (black) wire and current flow back in the neutral (white) wire. If the two don't match (i.e. some of the current is going anywhere else - like into you), it is SUPPOSED to disconnect the flow within 3-5 milliseconds to prevent you from being electrocuted. Like any other mechanical device, it can fail to perform as intended. That's why they have those test buttons on the front and a stamp that says "Test Monthly". For all new installations and all remodeling and all repairs, National Code requires them to be installed to protect all receptacles installed on all kitchen countertops (not just by the sink), unfinished basements, garages and outdoor receptacles with direct grade access. Like most codes, there are a (very) few exceptions - ask your professional.

Rule #1: Turn off the circuit at the panel!
Rule #2: Even if you're sure that the circuit is off, test it again anyway at the point of use with a voltage tester. You won't get a second chance!

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No one said GFCI was to protect the pc
by PKsteven / November 19, 2005 4:02 AM PST

Where did you get that? Did you read anyone elses post? And you are full of it. I live in Michigan buddy, I don't need a permit to change an outlet or rewire my home, not in the part I live in anyway, the only way I need an inspection or permit is if I am a liscensed contractor. It seems this origingal post has been dead for some time, what do people like you do, come here , read all the posts, post replies to them after browsing the net and scavaging for any info available? Buddy, I write almost everything from memory,not get info on the go. I can tell by your reply, it's out of focus, and why go into that kind of detail, why does he have to know 80% of the crap you wrote just to get a ground in his home or outlets?
All you did was repeated most of what others said, only not as organized. You are trying to show a knowledge you don't ACTUALLY have. It's sad some have to be like this.

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Re: wiring
by StageRt / November 19, 2005 8:55 AM PST

Steve; Aluminum wiring didn't come in, as stated, 'til the late 60s. Copper shortage due to ammunition requirements in VietNam. That said, you should have copper wire.
Most 'romex' used then could come with the ground wire as standard. As some noted, even though you have 2 prong plugs the ground may be there but is only attached inside the outlet box.
If it's there it's fairly simple to 'pigtail' a ground wire to the existing joint and attach it to your new receptacle.
As to the type of receptacle to use, I spent the extra money and got 'surge suppression' receptacles. Leviton and Hubble both have these available. You may have to go to a local electrical supply house and order it though. Both computers as well as several household appliances are plugged in using SS receptacles.
Surge suppression works somewhat like a series circuit, i.e. no single device is GENERALLY adequate to eliminate the surge on it's own. Several surge devices IN SERIES will significantly reduce the surge before it can get to your equipment.
Example: a SS at your panel, a SS receptacle AND a stand alone SS to which you plug the equipment in gives you 3 layers of protection.
I live in Florida and Surges are a continuing problem down here. We get a WHOLE BUNCH of lightning during the rainy season.
Where you live will determine how much of this you can or can not do without hiring some one. Each state and many counties have their own requirements.
As one poster stated though, if you decide to do this yourself, whether it's allowed or not, make SURE you do it right.
IF you feel comfortable working with electricity, I would run a new branch circuit to the new location. I would use 12/2 Romex. I do commercial electric and #12 wire is the smallest we use. You can put it on either a 20 or 15 amp breaker.
That's going to give you 'clean' power to the computer. Without tracing the other receptacles circuitry out, you won't know what else is on the circuit nor how 'dirty' the power is by the time it gets to that receptacle.

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(NT) (NT) very well put
by PKsteven / November 19, 2005 12:08 PM PST
In reply to: Re: wiring
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Agreed with most of the Tech Talk... Canada Calling...
by bobcan / November 20, 2005 6:38 PM PST
In reply to: (NT) very well put

As a "New Poster" from Canada (hello Southern Neighbors) I agree on most Real Tech thoughts here... You do need a Ground to have a viable method of "dumping" extra voltage if a spike occurs. Ultimately, the Ground and Neutral/ Common are a similar 0v potential to the Hot conductor. Some buildings may "bond" these together which is not always helpful... especially with what the Audio World calls a Ground Loop (that is the Voltage measured between Ground and Neutral). If you measure Absolutely "0" volts with a good DVM there is a very good chance they are the same/bonded and you may be advised to rewire your outlets. A real Ground will likely have less than One (1) volt A.C. across Neutral/ Ground.

In Canada we typically want the building Ground to be a Water Pipe (copper) as it will undoubtedly be the most assured of safely dumping any stray potential voltage.

Also, up here we have varying Grades of Wall Receptacles with one of my (and the Entetainment Industry) favorites being called "Spec Grade" ... Built better than the Cheap Plastic "12 for $5.99" types and should never fail in Household usage; usually $2.50 "ish" in some Quantity at suppliers. If you are wanting/ needing to Isolate a Ground better yet, the Orange colored "Hospital Grade" does not allow the Chassis to touch the Ground of a Metal wall box as a normal receptacle does when scewed into place. Accordingly, you must run a dedicated Ground cable to this type of plug... troublesome unless required and planned for in advance some times!!

Sorry to ramble on; hope some of this applies Down South as well... and BTW, as well up here we are allowed to work on our own Residential Wiring without Permits/ special Electrician Licenses... of course only advised if you are Comfortable and Knowledgeable on the work at hand!! Your household Insurance may frown on improperly done "reno's"...

Thanks to all for info on many great subjects; all the Best from Canada. Bob

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ya eh!
by PKsteven / November 20, 2005 7:07 PM PST

I'm from the U.P. of Michigan, pretty close in language. Input is always appreciated. Yeah, I think he needs to have his wiring looked over by an electrician, there's no telling what could be in there. The earth ground is more important than most think and what some don't realize is a fake ground has been put into many older houses, well, not a true one. It hooked to either the box or dissappeared into the wall, never to be seen going to the box. I always feel that if wiring is old, and IF you have the money, replace it by all means.I watched my house burn down at 11 years old and almost died in it, from an electrical fire. The wiring was from the 50's I think. So maybe that clouds my judgment, but I still feel it's the best way to go. Take care up there eh? Paul

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Detroit Rocks !!
by bobcan / November 21, 2005 8:40 PM PST
In reply to: ya eh!

From the Home town of Gordie Howe/ Tim Cheveldae/ the Kocur's and Wendel Clark....

Thanks for the "vote"... I am of the Old School mentality that it is good to know and ask questions on things that are this important; I am not too proud to admit I am wrong and any day I learn something new is A GOOD DAY!!

... As noted: if in doubt about your "Tech Abilities" please consult/ have a professional look into your problem as A.C. Powewr has the ability to Kill/ Burn you Down... Bye for now; Bob

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50/60 Hz vs. Surge Frequencies
by Always-Learning / February 20, 2016 11:11 AM PST

The return path via the Neutral wire or the Safety Ground at 50/60 Hz is not the issue (if it were, you would not be able to flip a switch to turn on the lights), it's at surge frequencies (typically 100 kHz, but also in the range of several kHz to several hundred megahertz) that the impedance chances. At 50/60 Hz, house wiring can have all sorts of bends and there is not an issue, but at surge frequencies it's an entirely different animal.

Here's a useful analogy, consider a hand gently breaking the surface tension of water & freely moving underneath the water. This is how it is for electricity. Now take the same hand, slam it as hard as you can into the water & you’ll encounter a lot of resistance, perhaps it will feel as if you hit a brick wall. This is how it is for surges. The water is analogous to the house wiring. At some frequency the surge hasn’t got a chance & will seek another path perhaps damaging our electronics in the process. That’s why spikes or transients which are often measured in billionths of a second are least likely to find their way, & often zap our electronics instead.

Here's an example that you will help to understand what's happening. #14 gauge house wiring has an inductance of about 2 micro Henries per meter, and a 50 meter (164 feet) run from an outlet to the mains electrical panel is not unheard of. The voltage, V across a an inductor, L is represented by the following expression, where di/dt represents the rate of change of the current in the inductor (house wiring):


A representative lightning surge on the AC mains might have a short-circuit current waveform of 500 amps peak with a rise time of 8 microseconds. Applying these values to a 100 micro Henry inductor, the calculated voltage comes out to:

(0.0001)*(500/0.000008)=6,250 volts

Large surge currents with fast rise time can generate voltage drops of several thousands volts on a long grounding wire.

In an MOV based surge protector, or an all-in-one MOV based surge protector, the MOV's for the AC mains turn on at 330 to 400 Volts (or more), and the surge current attempts to flow through the AC outlet's ground wire back to the electrical panel. If a 6,000 voltage drop develops across the length of the ground wire, the entire ground reference node within the surge protector rises to an instantaneous potential of 6000 volts above earth ground.

This has the effect of lifting the surge protector end of every connected cable (AC mains, Ethernet, phone and/or coax) to an instantaneous value of 600 volts above earth ground. At this point, surge currents would normally be expected to exit through the ground connection may find other, more attractive paths to a ground through the connected cables.

The key point here is that a high current, fast rise time on the AC mains can interact with the inductance of the ground wire to create a high voltage common mode surge on every cable that is connected to the surge protector. In some sense, the surge protector takes a surge on the AC mains and "broadcasts" it onto every cable that is connected to the surge protector. This happens despite the fact the surge protector has been installed correctly and the ground wire of the AC mains outlet is connected properly.

Unless we can install a ground rod at every Type 3 SPD or keep the wiring runs short this kind of protection lulls us into a false sense of security.

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by Corrupt_Data / December 5, 2005 9:28 AM PST

I also have an older home (Mid-1950's) which had mostly 2 prong outlets, with the exception of certain upgraded areas. We upgradede the important computer areas to 3 Prong Outlets and Grounded them to the main electrical panel. I have since tested it and confirmed a ground.

The other posters are correct, grounding is necesary for your surge protector's protection function to work, and for your safety, to discharge things like static electricity. A dedicated circuit is not necesary, but it never hurts. I have two circuits for computers, and one for small appliances in my LAN Party Room.

Computers also tend to have strange problems when they're not grounded, aside from surge damage, things like over voltage can cause shorter equipment life, and excess static without a discharge path can cause the monitor to become blurry or hard to read. Etc. A UPS is no different, both require a ground for safety and protection on both the equipment and human level.

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For Type 3 SPD MOV surge protectors
by Always-Learning / February 15, 2016 4:21 PM PST
In reply to: Yes...

Just because you have a ground that you checked with a meter does not necessarily mean that you have a "low impedance" path to the ground.

When diverted by the MOV to the Neutral and/or Ground wires the surge energy needs a low impedance return path to the panel, otherwise it will seek an alternate path even if through the electronics we’re trying to protect or any device plugged into the same branch circuit.

Ground is a zero volt reference voltage by electronics and modern appliances. It’s expected to be at zero volts and it wasn’t designed to be used as a place to dump a surge. When a surge is on the ground, strange things can happen: unexplained hard drive crashes, fried motherboards or circuit cards, bad USB ports, premature power supply failures, hum & noise the audio, noise/pixelization in the video and the most common: failed HDMI ports. Ground contamination is a big issue.

At 60 Hz (low frequencies) electricity has a low impedance path on the Neutral wire even with several 90 degree turns by the time it gets back to electrical panel. You can prove this by flipping a light switch and watching the light turn on. Ideally house wiring should be point to point with no 90 degree turns but often times that isn’t the case. Surges can be very fast (high frequencies) & the house wiring can suddenly represent a high impedance return path, causing the surge to seek another path to ground through the electronics we’re trying to protect.

By way of an analogy, consider a hand gently breaking the surface tension of water & freely moving underneath the water. This is how it is for electricity. Now take the same hand, slam it as hard as you can into the water & you’ll encounter a lot of resistance, perhaps it will feel as if you hit a brick wall. This is how it is for surges. The water is analogous to the house wiring. At some frequency the surge hasn’t got a chance & will seek another path perhaps damaging our electronics in the process. That’s why spikes or transients which are often measured in billionths of a second are least likely to find their way, & often zap our electronics instead.

Short of redoing the wiring, there is another solution that uses a series mode filter (made by Zero Surge, Brickwall or SurgeX). These filters are heavy duty low pass filters designed to "slow" the surge down in real time (recall the hand in water analogy). When you slow the surge down, you eliminate all the issues associated with internal house wiring and whether there is or isn't a low impedance return path. No manufacture knows what your house wiring looks like. Its not sweat to them if the path is high impedance and the surge goes elsewhere & there are so many loop holes and escape clauses in the connected equipment warranties that all this has been factored into their decision to sell this type of protection to begin with.

Remember that when you use a meter you're basically testing at DC not at the frequencies that surges occur at.

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For 2-wire systems
by Always-Learning / February 15, 2016 4:27 PM PST

Since series mode power filters don't rely on an MOV and don't divert the surge to ground, they are an excellent solution for homes with 2-wire outlets. You can use a ground lifter (3-prong to 2-prong) adapter with them and here's the best part:

You can plug your MOV based surge protector (the ones with all the fancy spaced outlets) into the series mode power filter to expand the number of available outlets. You can also plug a UPS into it to protect the UPS.

The series mode power filters are designed to withstand 1000 of the harshest surges that can existing on house wiring inside a building which amounts to 10 years worth of harsh surges without performance degradation.

You can buy them used on popular auction sites for as little as $30 so it won't break the bank. Even new units run $140-$160 plus shipping and if inrush current elimination is of interest you can look a the SurgeX SX1115-RT Advanced Series Mode products. I bought 4 units (3 used from $50-$150 and 1 new old/stock for $150).

Secure the coax/phone connections (if still used) at the service entrance an lastly at a Type 2 Whole House SPD in the mains electrical panel. Now you have a layered approach and don't have to worry about impedance issues for surges on type 3 SPD's in the house.

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Reality is Found Elsewhere
by w_tom / February 21, 2016 7:53 AM PST
In reply to: For 2-wire systems

Series mode filters do not even claim to protect from destructive surges. 'Slowing a pulse' distorts reality as if electricity operates like water.

Anything that foolishly tries to 'block' that current means voltage increases as necessary to blow through that 'blocker'. Anything that series mode protector might do is already done better inside appliances. Anyone can even learn from numbers. That series mode protector only claim to absorb maybe 600 joules. That is less protection than inside near zero power strip protectors. Even appliances can convert near zero 600 joules surges into low voltage DC to safety power its semiconductors. Why spend so massively on a near zero protector? Junk science.

As others so bluntly stated, protection is always about where hundreds of thousands of joules harmlessly dissipate - in earth ground (not safety ground in a receptacle). Effective protectors (ie one in the breaker box) means hundreds of thousands of joules remain harmlessly outside. Somehow 2 cm parts inside a magic filter will block what three miles of sky could not? Somehow it will make hundreds of thousands of joules just magically disappear?

Series mode protector may cost about $130 per protected appliance. The informed homeowner earths a 'whole house' protector for about $1 per protected appliance. Why does a vastly superior product also cost so much less money? A proven and recommended solution is based in over 100 years of well proven science and experience. With numbers that define why hundreds of thousands of joules remains outside - need not do any damage. Somehow an expensive magic box will block what three miles of sky could not by claiming electricity works like water. By claiming it will somehow absorb hundreds of thousands of joules.

Always-Learning only promotes series mode protectors. His claims routinely ignore well proven facts and numbers. As if 2 cm parts can magically 'block' or 'absorb' what three miles of sky could not. Facilities all over the world that cannot have damage always properly earth ground (not safety ground) a 'whole house' solution.

Protection is always about where hundreds of thousands of joules dissipate. Effective solutions always connect low impedance (ie less than 10 feet) to what harmlessly absorbs even direct lightning strikes - earth ground. Series mode protectors have no earth ground. So it makes hundreds of thousands of joules just magically disappear? How does its maybe 600 joules make hundreds of thousands of joules magically disappear? It doesn't. It makes your money disappear.

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Name Just 1
by Always-Learning / February 21, 2016 8:48 AM PST

Name Just one Type 1, Type 2, or Type 3 SPD that can absorb hundreds of thousands of joules? Just one? You can't because nothing can't. So your examples are tiring, retreads that you've been posting on Usenet and the Internet for the last 2 decades. Do some more reading and/or learning

A series mode power filter's intended application is in a Type 3 SPD environment in-lieu of surge diverting & hope for the best situations. You haven't learned yet.

And by the way, if you don't have a good earth ground at the service entrance, a Type 2 SPD will fail miserably.

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Surge protector or UPS
by calvina251 / February 19, 2016 10:58 PM PST

Surge protector or UPS is the same it is necessary for any electronic equipment the power supply or Vcc be grounded depending on the power status that var from country to country. So we should effective power grounding facilities for each and every appliance that we use.

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by Always-Learning / February 22, 2016 11:24 AM PST
In reply to: Surge protector or UPS

Yes, proper grounding is required even for a light bulb to turn on & that grounding is at the service entrance.

All 2-prong outlets consist of a LINE (HOT) and a NEUTRAL (GROUND), a 3-prong outlet adds a GROUND (SAFETY GROUND) feature.

2-prong outlets were part of the National Electric Code and when the code is revised, the old rules are grandfathered in, else all us would have to spend considerable sums of money rewiring our homes just to keep up with the newest revision. Does that mean that homes with 2-wires are bad? No, just that one has to be more careful.

I think care must be taken when stating what type of Surge Protector or UPS is used.

Surge Protectors come with triple mode protection (L-N, N-G, L-G) and many UPS have built-in Surge Protectors with the same triple mode protection (L-N, N-G, L-G).

Using a triple mode SPD in a home with a 2-prong outlet would mean protection would only be across the L-N connections, but the surge would continue to be diverted to the L-G and go where?

Some companies still make MOV surge protectors that work by diverting the surge from L to N only and this might work in a home with a 2-prong outlet. But then the UPS could not since it has a triple mode SPD built in. That's not even considering the larger issue namely when the surge is diverted to the NEUTRAL will it have a low impedance path back to the mains electrical panel? At 50/60 Hz this isn't an issue but at surge frequencies without a low impedance return path the surge seeks alternate paths.

A series mode power filter works entirely different from MOV based SPDs which divert the surge and hope for a low impedance return path.

Series Mode Power filters:
(1) work continuously on di/dt (fast rising currents),
(2) work continuously on dv/dt (no threshold needed for the voltage)
(3) suppresses the surge
(4) does not divert the surge to ground
(5) can be used in 2-wire residences without a safety ground
(6) can plug any MOV based SPD into a series mode to expand the number of available outlets, and
(7) can plug a UPS into a series mode to protect & prolong the life of a UPS

Here's some links you can read:
(1) 2-wire homes
(2) How series mode works:
(3) Importance of Proper Grounding at the Service Entrance:

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More Fables
by w_tom / February 22, 2016 11:53 AM PST
In reply to: NEC

> Yes, proper grounding is required even for a light bulb to turn on & that
> grounding is at the service entrance.

Absolute nonsense only possible when one has no electrical knowledge. Anyone can see two prongs on a lamp cord. No ground (third prong) exists. Light bulb works fine. Even the building's earth ground can be disconnected. And all light bulbs still work just fine.

This same person also recites propaganda (and no numbers) from series mode protectors as if fact. No numbers is a first indication of fables. Everyone can see light bulbs work just fine with no safety ground wire.

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