Discussion on UPS and power surge protectors

[Automata]

Going based on the previous posts and where I think I see this thread heading, I'm very close to washing my hands of this argument and close the thread. I'm not in on this argument and I'm tired of being caught in the crossfire. While it is fun watching you guys duke it out, it gets old pretty fast.

Bottom line: If anyone is going to contribute to this thread, post facts and back them up with proof. If you don't want to contribute to thread thread, argue semantics, or just throw personal insults around, get out.

 

[bud--]

I posted only facts with numbers.

With respect to plug-in protectors (which is intended to include UPSs) westom posts his opinions and misconstrues what other sources say.

One of the first times I saw westom was on an electrical engineering form where he mischaracterized the views of researcher Arshad Mansoor and provoked a response: "I found it particularly funny that he mentioned a paper by Dr. Mansoor. I can assure you that he supports the use of [multiport] plug-in protectors. Heck, he just sits down the hall from me. LOL."

If that UPS does more than just battery backup, then please, quote the spec number.

I have posted specs for plug-in protectors. Others have posted specs for plug-in protectors. They are always ignored by westom. Apparently he knows that plug-in protectors do not work so specs can not exist.

Show me what it is wrong

The whole thread has shown where westom is wrong.

The problem, if anyone is interested, is that westom has an apparently religious belief (immune from challenge) that surge protection must directly earth a surge. Since plug-in protectors have relatively high impedance to earth westom believes that they can not possibly work. He ignores the clear explanation of how they work in the IEEE surge guide (limit the voltage from each wire to the ground at the protector). Westom ignores anything that conflicts with his simple beliefs.

Westom is evangelical in his belief and googles for "surge" in his compulsive crusade to save the world from the scourge of plug-in protectors (and UPSs).

Never answered - obvious questions:
- Why do the only 2 detailed examples of protection in the IEEE guide use plug-in protectors?
- Why does the NIST guide says plug-in protectors are "the easiest solution"?
- Why does the NIST guide say "One effective solution is to have the consumer install" a multiport plug-in protector?
- Why does the NIST guide say "Plug-in...The easiest of all for anyone to do. The only question is 'Which to choose?'"
- Why do westom's "responsible companies" make plug-in protectors?
- Why does "responsible company" SquareD says "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use"?

For real science read the IEEE and NIST guides. Excellent information on surge protection from reliable sources. And both say plug-in protectors are effective.

Then read the sources that agree with westom that plug-in protectors do NOT work. There are none.

 

[hokiealumnus]

My god. I even said 'why' each point is valid. Sometimes even quoting professional sources. How many more facts, numbers, and sources should I cite?

How about one? Or two? Or as many for as many points as you seem to be attempting to make? I see not one citation in any of your posts in this thread (other than a single IC datasheet), yet I see bud-- has two sources -one from the IEEE and the other from the NIST- from which he has made points refuting what you say. In the post above this one, he seems to do a pretty solid job of characterizing the reasons for your posting too.

We will not tolerate continued obvious attempts at supporting your point of view by attacking other posters (not personally, but attacking their points) with giant posts without supporting your arguments. I'm not saying you're wrong, heck I don't know enough about this stuff to even actually wade into the discussion in a helpful manner, but I call a spade a spade and you, sir, are not supporting your position with anything resembling research or factual citations that I can see. Begin doing so or cease posting.

 

[westom]

How about one? Or two? Or as many for as many points as you seem to be attempting to make? I see not one citation in any of your posts in this thread (other than a single IC datasheet), yet I see bud-- has two sources -one from the IEEE and the other from the NIST- from which he has made points refuting what you say.

Read those citations. The NIST says:

You cannot really suppress a surge altogether, nor "arrest" it. What these protective devices do is neither suppress nor arrest a surge, but simply divert it to ground, where it can do no harm.

Divert it to earth ground where hundreds of thousands of joules harmlessly dissipate. So that the surge current does not go hunting for earth destructively via appliances. The NIST then says protectors promoted by bud are "useless".

A very important point to keep in mind is that your surge protector will work by diverting the surges to ground. The best surge protection in the world can be useless if grounding is not done properly.

As I have been saying all along.

bud says earth ground is unnecessary. That energy will magically disappear if the protector is adjacent to the appliance. Page 42 figure 8 in the IEEE citation. If too close to appliances and too far to earth ground, then the protector may earth that surge 8000 volts destructively via any nearby appliance. Any appliance connected to the protector OR any other nearby appliance (TV2).

Again, protector only connects a surge to earth. If not adjacent to earth, then the protector may even earth that surge destructively via any nearby appliance. Once that surge is inside, then nothing - as in nothing - will avert the destructive hunt for earth.

Not just the NIST and IEEE say this. The list is quite long. How many tens of citations would you like? Virutaly every professional organization defined protection in terms of single point earth ground.

Ask and I will provide too many hours of reading. Remember, I did this stuff. Direct lightning strikes without damage should be routine.

 

[EarthDog]

How many tens of citations would you like?

Can you start with one? I see no links above. Understand nobody knows you (or anyone in this thread) from a hole in the ground. Support what you are saying with links like others have and perhaps your words will be discussed more appropriately. Answer buds questions with supporting links. Thats all. Its simple really.

Ask and I will provide too many hours of reading.

It appears people have asked ad nauseum already (both in this thread, and the others hokie posted links to initially)...did you read bud's requests? Hokie's?

 

[westom]

Can you start with one?

Let's start with Gary Coffman:

Well I assert, from personal and broadcast experience spanning 30 years, that you can design a system that will handle *direct lightning strikes* on a routine basis. It takes some planning and careful layout, but it's not hard, nor is it overly expensive. At WXIA-TV, my other job, we take direct lightning strikes nearly every time there's a thunderstorm. Our downtime from such strikes is almost non-existant. The last time we went down from a strike, it was due to a strike on the power company's lines knocking *them* out, ...

Since my disasterous strike, I've been campaigning vigorously to educate amateurs that you *can* avoid damage from direct strikes. The belief that there's no protection from direct strike damage is *myth*. ...

The keys to effective lightning protection are surprisingly simple, and surprisingly less than obvious. Of course you *must* have a single point ground system that eliminates all ground loops. And you must present a low *impedance* path for the energy to go. That's most generally a low *inductance* path rather than just a low ohm DC path.

To lightning, AC electric wires, underground phone wires, etc are same as an antenna wire connected to each appliance. Some of the earliest users of surge protection were ham radio operators in the early 20th Century. They would even disconnect the antenna wire, put it inside a mason jar, and still have damage. Even disconnecting was insufficient. Damage stopped when they earthed the antenna wire.

A Nebraska radio station also suffered constant damage. Station engineers foolishly assumed ground were causing the damage. They even disconnected grounds making protection worse. Eventually a professional was brought in to eliminate damage. A case study is at:
http://www.copper.org/applications/electrical/pq/casestudy/nebraska.html

They installed no protectors. Fixed all earth grounds including the AC electric grounds. Building grounds are only the 'secondary' protection layer. Each protection layer is only defined by its earth ground. Note the solution to the 'primary' protection layer - a ground at the utility power transformer. Damage eliminated only when the earthing was fixed.

That was three. Is this what you were asking for? Previously I only explained how all effective surge protection is installed - and why. Provided were the simple concepts necessary to have effective protection. If you want professional citations rather than useful instructions, I can also provide that. But nobody asked for these citations. Even the NIST and IEEE citations define why earthing is so important. Most posts were only accusatory - not requests for citations.

An application note demonstrates how protection is installed. Two structures. Each has its own single point earth ground. Any wire entering each structure (even if underground) must first connect to the single point earth ground:
http://www.erico.com/public/library/fep/technotes/tncr002.pdf

Again, another notes the always critical low impedance connection to earth.

That app note also introduces another important concept - equipotential. Was not discussed because the topic was how to implement a solution; not the engineering technicalities that make 'whole house' protection the only solution found in every facility that cannot have damage.

 

[EarthDog]

I dont see the link or know who Gary Coffman even is... but you are well on your way outside of that (finally).
Now, if you can actually respond to bud and BobN who refuted your statements instead of continuing to force your point here, you can begin to have a healthy discussion on the topic.

If you want professional citations rather than useful instructions, I can also provide that. But nobody asked for these citations. Even the NIST and IEEE citations define why earthing is so important. Most posts were only accusatory - not requests for citations.

Sir, you should re-read those posts from bud as there are clear requests for this kind of information (to me). Perhaps look through the frustration they have shown and deal with the content. GL guys... Im out.

 

[Bobnova]

I'm back! There's too much FUD here for me to ignore it.

Westom, do you have an answer for any of the following questions you've been asked? Ideally, all of them?

Never answered - obvious questions:
- Why do the only 2 detailed examples of protection in the IEEE guide use plug-in protectors?
- Why does the NIST guide says plug-in protectors are "the easiest solution"?
- Why does the NIST guide say "One effective solution is to have the consumer install" a multiport plug-in protector?
- Why does the NIST guide say "Plug-in...The easiest of all for anyone to do. The only question is 'Which to choose?'"
- Why do westom's "responsible companies" make plug-in protectors?
- Why does "responsible company" SquareD says "electronic equipment may need additional protection by installing plug-in [protectors] at the point of use"?

Also, what does the NIST say about what a "proper" ground is? Please cite with a link to the guide and a page number, not just a copy/paste. If you're going to convince us you're going to have to cite things properly.


On the subject of capacitors: Do you know the difference between a non-PFC appliance and capacitors, a passive PFC appliance and capacitors, and an Automatic PFC appliance and capacitors?
In my capacitor based examples I said APFC multiple times, an APFC takes the incoming voltage and actively boosts it to ~380v before storing it in a capacitor. In PSUs that capacitor is rated for somewhere between 380v and 450v. I've yet to see a higher rating.
The APFC circuit can completely ignore a surge up to that voltage point, as it will not even get through the PFC boost diode and into the capacitor until the voltage is higher than 380v. For bonus points most PSUs these days have a TVS Diode (NOT a MOV. They serve the same function but have very different specs) that triggers in the 400v range somewhere. That mops up a lot more surges.
It is wired across the live and neutral wires.

A passive PFC unit uses a voltage doubler and two 200v capacitors to achieve a voltage somewhere in the mid to high 300v range. Crucially the capacitors are wired in series (sort of) so each capacitor only has to deal with half the voltage. They also have a MOV or TVS Diode, wired the same way, for the same purpose: deflecting surges.

A non-PFC unit is much simpler, it just rectifies the incoming voltage to DC and stashes it in a capacitor. That capacitor is probably rated for around 200v. I have no experience with them and cannot comment on their internals.

Now like I said, I was talking about APFC computer power supplies. Let's step through what happens in a surge, shall we?

Surge begins, voltage rises and current starts to flow.
The APFC unit says "Oh ok, that's cool, I can auto-range between 90v and 264v!" and keeps on doing what it wants to do and drawing exactly as much current as it wants to.
Meanwhile the surge continues, it cannot dump all the current it wants to, so the voltage continues to rise.
At 264v (AC mind you, so ~373v DC. Familiar sounding number?) or so the APFC says "Uhh hey, we're kinda done here man" and does one or two things.
The first thing is to stop boosting the voltage, it doesn't have to. It'll still boost it in the off-peak areas, but not peak.
The second thing it may do, if the APFC voltage goes too high, is to shut down the primary switches for the PSU's DC-DC regulator.
These switches are rated at between 500v and 800v in my experience.
I checked the datasheet for two different 600v-650v units and both suffer avalanche breakdown at 700v. At that point you have 700v going through the PSU's transformer rather than 380v, and odds are it's game over.
However, 700v is far higher than the trigger point of the TVS diode. It opens up (quickly, a few picoseconds) and starts dumping the surge to neutral. Note that a PSU does not care what the hot-ground voltage is, only hot-neutral. The primary side of the unit (that which deals with line voltages) is isolated from ground. The entire APFC unit is, so it only cares about the difference between live and neutral.
Anyway, once the TVS diode is dumping it can flow a huge number of amps. In a brief surge it will simply deflect it for the duration of the surge, the APFC bits never see it. Just past the TVS diode is the transient filter, which further serves to delay a brief surge.
In a longer surge the obscene current through the TVS diode will blow the fuse, no more issues.

Now please note that the above example doesn't require a ground path at all due to the way APFC PSUs are designed.



Bonus: A post occurred while I was typing.

I think I see where your confusion comes from.
That first link and its TVSS info states it requires a good ground. Because it does.
The issue they were having previous was due to bad, horribly wired, grounds. That's a major issue.
It also has absolutely nothing in common with a house that doesn't have neutral tied to ground.
Note that nowhere does it say it must be less than ten feet to anything.
Neither link says anything about internal surge protection, either.

The first block quote is quite literally useless. I could type one up from Joe Smith that supports my points too. He has 45 years of experience.


Now I need to take my kids to school, but rest assured that I'll be back soon.

 

[westom]

Sir, you should re-read those posts from bud as there are clear requests for this kind of information (to me).

The answers to bud posts were posted hundreds of times over most of the past ten years. He follows me everywhere. Joining groups only because I posted there. It is his job. His is paid to post this stuff. His accusations (including one about airplanes) have been replied to often. (How often does your house fly through clouds? Why is that relevant?)

I have asked him this for years. Post the manufacturer spec numbers that claim protection. He never does because those numbers do not exist. So he replies saying he already did so.

If something in his post had merit to you, then you ask about it. Most of his posts are half truths and quotes taken out of context. But again, his job is sales; not engineering. Discussions with bud only result in nasty and derogatory personal insults from him. You ask questions. Then I provide answers. We don't need him.

The ARRL repeatedly has artilces about protecting equipment (in their case the ham radio station) from surges. In 2002 entitled "Lightning Protection for the Amateur Radio Station". For example,

The purpose of the ground connection is to take the energy arriving on the antenna feed line cables and control lines (and to a lesser extent on the power and telephone lines) and give it a path back to the earth, our energy sink. The impedance of the ground connection should be low so the energy prefers this path and is dispersed harmlessly. To achieve a low impedance the ground connection needs to be short (distance), straight, and wide.
...
The goal is to make the ground path leading away from the SPGP more desirable than any other path.

Protectors are simply science. The art of protection is the earthing. I tried to introduce that art without becoming too technical. But protection, as every quoted source notes, is about the earthing. And about a low impedance connection to that earth ground.

Another had a real problem getting a good earth. Ufer first implemented Ufer grounds in munitions dumps so that direct lightning strikes did not cause damage. Why conductors in concrete? Because concrete is an electrical conductor. Appreciate how he implemented an Ufer ground - better earthing. Because, as he noted, better earthing defined better protection:
http://scott-inc.com/html/ufer.htm
http://www.psihq.com/iread/ufergrnd.htm

 

[EarthDog]

The answers to bud posts were posted hundreds of times over most of the past ten years.

Not here. You brought this here and need to support your assertions. Its just that simple. If bud came here and did the same thing you did, bud would be getting the business as well.

Im not going to get in to the issues of you and bud, but after googling and looking, it seems for nearly a decade that a lack of citing/sourcing your posts is your MO and the source for much of the frustration among those threads and of course here (even in 09.. no sources, but nobody called you out then). I am trying to help you help yourself so the FACTS get out to people that come across this thread (regardless of who is right or wrong). So far, its been like pulling teeth, but hopefully, with you starting to source your information, I think the Novocaine is within reach.

Keep sourcing your statements and this discussion will hopefully become more fruitful.

Anyway, we have beaten the dead horse... and I will bow out to let those that have a clue WTH this is about discuss the merits.

 

[wagex]

i think everyone should just do their own thing for surge protectors its all a matter of preference, weather it works or not it makes people feel better about their stuff. stop trying to cram stuff down peoples throat. weather they work or not, is irrelevant to half the conversations here in this thread. i honestly think it should be closed because there is absolutely no progress being made here, just bickering over senseless inquiries.

and +1 to bobs big yellow statement on the page before.

 

[westom]

Also, what does the NIST say about what a "proper" ground is? Please cite with a link to the guide and a page number, not just a copy/paste. If you're going to convince us you're going to have to cite things properly.

No source says 'less than 10 feet'. That is a ball park number for homeowners to better define the concept called low impedance. Low impedance is an art. If the appliance is within tens of feet of the protector, then that short connection might be even shorter - ie 'less than 3 feet'. But again, wire resistance (ie wire thickness) has little relevance in surge protection. Far more important are low impedance and a ground wire separated from other non-grounding wires.

Also critical are equipotential and conductivity. Both are required in the earthing electrode because neither can be good enough. But those concepts are also typically too advanced for the average consumer and some electricians.

The NIST is an executive summary dumbed down for consumers. But the point remains. A protector connects energy to the earth ground. Or that protector is "useless". Protection means one can say where hundreds of thousands of joules dissiapte. And can say what a path is from cloud to earth; and then miles to earthborne charges. Even nearby interstate pipelines, how electric lines distribute power, geology, and a well are significant factors.

Ground wires not inside metallic conduit is also not specially stated. But engineering knowledge says why conduit increases impedance.

A similar solution is also demonstrated in the application note of two structures. Notice all wires entering through a metal panel. That panel also increases impedance between the surge and equipment. We want low impedance to earth. And high impedance between protector and equipment. Longer wire also increases protection. Telcos often want up to 50 meter separation between protector and equipment. These are well proven techniques used to implement the 'art'.

Point remains. Serious protecton already exists in all appliances. We are concerned with the destructive surge. It occurs maybe once every seven years (a number that can vary even inside a town; even varies with geology). Earth the rare and destructive surge so that all surges cause no damage. So that protection already inside all appliances is not overwhelmed.

I did not realize that APFC was refering to active power factor correction. That would explain a 400 volt capacitor (non-polarized?). Active PFC (98%) is quite rare. I was dicussing classic power supplies routinely found throughout the world.

Meanwhile TVSS or MOVs inside appliances only address normal mode transients. Destructive surges are longitudinal mode. That means a transient entering on some wires results in near zero voltage across the TVSS. While also creating 8000 volts destructively via that appliance (in the IEEE brochure).

For example, a protector has a let-through voltage of 300. A 6000 volt surge approaches only on one wire; the hot (black) wire. That protector simply puts 5700 volts on the neutral (white) and safety ground (green) wires. Now the surge has more wires to find earth destructively via the appliance. We even traced this exact damage through a network of powered off computers. The adjacent protector bypassed power supply protection. Connected (earthed) the surge directly into the motherboard.

So what did that 300 volt TVSS do? Make damage easier. Gave a surge more paths to find earth destructively. Bypassed PSU protection. Also why so many manufactures no longer implement three MOVs internally. It does not protect from the other and typically destructive transients. In some cases, it increased fire risk or makes damage easier.

So how does that current get to earth? Is the path harmless (earthed at the service entrance)? Or does it go hunting for earth inside the house?

Well, one home had a properly earthed 'whole house' protector. And still had damage. Unfortunately, on the far side was a buried vein of graphite. Surges were still entering on AC electric to find that better earth destructively through appliances (and building materials). In this case, better equipotential was required. The house was encircled with a single point earth ground. Then no more appliance damage. Again, 'art' of protection is the earthing.

 

[westom]

In a longer surge the obscene current through the TVS diode will blow the fuse, no more issues.

That introduces another concept in protection - follow through current. Destructive surges are often low energy events. (the same high energy event is now, in this paragraph, low energy). A surge not properly earthed can create plasma paths (similar to what is inside a fluorecent bulb). That plasma then connect a high energy surge (ie utility's 33,000 volt primary wire) directly into all appliances. This resulting follow through current is why some see exploding appliances or sparks from wall receptacles.

Proper protection means the relatively low energy transient (lightning) does not create those plasma paths. Or more specifically, that is why the utility power transformer must always have that ground wire that so many copper theives are stealing.

 

[hokiealumnus]

With two more posts-sans-reference, after staff discussion, we're done here. westom, in the future, back up what you're saying with references or do not post. You have been asked numerous times yet fail to do so, thus your posts are to most people are meaningless. If you do not wish to do that, that's fine; just don't enter the discussion.

To all else, thank you for your patience and for maintaining composure throughout the thread.

Thread closed.