Has anybody ever had a surge protector start smoking?

Factual Questions
21

Over 40 years ago, 120 volt electronics were required (by international design standards) to withstand up to 600 volt transients without damage. A line filter, galvanic isolation, etc are part of that internal protection. Many so-called surges are only noise due to existing protection.

Protection is required for typically destructive surges. Many will spend $10 to $120 per appliance for a strip protector. But one ‘whole house’ protector means effective protection for about $1 per appliance.

A destructive surge is rare - maybe once every seven years. Informed homeowners know the furnace, air conditioner, dishwasher, TV, clocks, dimmer switches, GFCIs, recharging smart phones, and computers need that protection. What most needs protection from a destructive surge? Smoke detectors. Especially when the best solution costs so little.

TV cable already has best protection - a wire direct to earth where cable enters the building. Telephones have long made the same connection via a ‘whole house’ protector installed for free by the telco. Code required these for longer than anyone here has existed.

But the most common source of destructive surges is AC electric. A ‘whole house’ protector is installed in the breaker box or in the meter pan. Even the electric company can install one behind their meter. Nothing in that hagergroup.ae citation meets even minimal requirements.

And still many did not grasp what is most important. Most every question should be about the protection; not the protector. Most every question should be about the only component that provides protection: single point earth ground. Not one question yet about what is most important.

Protectors have a life expectancy … that is irrelevant when properly sized. A protector is only a connecting device. To connect at least 50,000 amps to earth on a wire that cannot even have sharp bends or splices. The art and most question should be on what does protection: earthing electrode and connections to it. Undersized protectors need be replaced every five years.

A best solution is also the least expensive. Is necessary to protect power strips that might otherwise cause a house fire. No viable reason exists to not have one connected to what does protection by both meeting and exceeding code requirements.

22

Excellent information on surges and surge protection is at:
http://www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf

  • “How to protect your house and its contents from lightning: IEEE guide for surge protection of equipment connected to AC power and communication circuits” published by the IEEE (the IEEE is a major organization of electrical and electronic engineers).
    And also:
    http://www.eeel.nist.gov/817/pubs/spd-anthology/files/Surges%20happen!.pdf
  • “NIST recommended practice guide: Surges Happen!: how to protect the appliances in your home” published by the US National Institute of Standards and Technology

The IEEE surge guide is aimed at people with some technical background.

Complete nonsense.

Myths are from westom.

The author of the NIST surge guide looked at the amount of energy that could make it to a plug-in protector (some of this is specific to features in US wiring). Branch circuits were 10m and longer. The surges coming in on power service wires were up to 10,000A. That is the maximum that has any reasonable probability of occurring, and is referenced in the IEEE surge guide. The maximum energy absorbed at a plug-in protector was a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. Plug-in protectors will all have much higher ratings than that.

One of the reasons the energy is so low is that at about 6,000V (US) there is arc-over from service panel busbars to the enclosure. The established arc is hundreds of volts. Since the enclosure is connected to the neutral and earthing system (US) that dumps most of the surge energy to earth. The other reason is the impedance of the branch circuit for the relatively high frequency current components of a surge. But it is all too complicated for westom

Of course it doesn’t. Plug-in protectors do not work by “stoping”.

Many manufacturers back up the advertising with warranties on protected equipment. One reason they can have the warranties is the amount of energy that can make it to a plug-in protector is much smaller than imagined.

May be true for the cheap crap that wesom buys. What I buy is competently engineered.

The normal failure mode for MOVs (which are the protection elements in the vast majority of surge protectors) is they start to conduct at lower voltages and eventually conduct at normal voltages and go into thermal runaway. UL has, since 1998, required thermal disconnects for overheating MOVs.

Unknown is whether Sampiro’s smoke is from MOVs, and whether the MOVs have thermal disconnects.

The IEEE surge guide describes at length how the protected load may be connected across the MOVs and be disconnected with the MOVs if they fail, or may be connected directly to the incoming line. If the first method is used the protected load is not left exposed if the protector fails. Connecting this way is probably another reason why some protectors can have protected equipment warrantees.

If I remember right, UL requires protectors sold now to make clear if they do not disconnect the protected load

Service panel surge protectors are a real good idea.
But from the NIST guide:
“Q - Will a surge protector installed at the service entrance be sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances [electronic equipment], No for two-link appliances [equipment connected to power AND phone or cable or…]. Since most homes today have some kind of two-link appliances, the prudent answer to the question would be NO - but that does not mean that a surge protector installed at the service entrance is useless.”

Service panel protectors are very likely to protect anything connected only to power wires from a very near very strong lightning strike. The NIST surge guide suggests most equipment damage is from high voltage between power and signal wires. Service panel protectors may or may not protect equipment that also has a connection like phone or cable.

The IEEE surge guide has recommended ratings for these protectors.

Nope.

Plug-in protectors do not work primarily by earthing surges. As the IEEE surge guide explains, earthing occurs elsewhere in the system. The guide explains (starting page 30) that plug-in protectors work primarily by limiting the voltage from each wire (power and signal) to the ground at the protector. The voltage between the wires going to the protected equipment is safe for the protected equipment.

When using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections, like coax also must go through the protector.

Contrary to westom’s diatribe, both the IEEE and NIST surge guides say plug-in protectors are effective.

23

All these “responsible” manufacturers except SquareD and Polyphaser make plug-in protectors and say they are effective. Westom says plug-in protectors don’t work.

SquareD says for their “best” service panel protector “electronic equipment may need additional protection by installing plug-in [protectors] at the point of use.”

I have not seen a protector at Lowes or Home Depot costing less than $50 that has westom’s rating of “at least 50,000 amps”.

My comments center on plug-in protectors because of the ignorance westom spreads all over the internet about them.

24

Bud forgot to admit one small fact. He is paid to promote plug-in protectors. Even the IEEE and NIST says a protector without earth ground may even cause appliance damage. But that honesty might cause him unemployment.

Bud is my pesonal troll. He has followed me for about ten years now posting half truths and lies, and bogus accusatiojns. It is his job. Meanwhile every professional organization says earth does the protection. IEEE makes recommendations bluntly in standards. From the IEEE Red Book Standard 141:

From the IEEE Emerald Book:

From the IEEE Green Book Standard 142:

Even all major equipment provider require earthing. For example Sun Microsystems:
“Planning guide for Sun Server room”

If a protector does not “divert the power of the surge [on a] path to ground”, then that protector is ineffective. Then Bud would be unemployed. And would not be paid to post nasty and fictious accusations.

What bud fears you might learn: a protector is only as effective as its earth ground - as the IEEE, NIST, Sun Microsystems, and other professionals all state.

25

My only association with the surge protection industry is I am using some surge protectors.
Perhaps westom could deal with science.

Cite.

That would take a time machine. I first saw westom much more recently when he repeatedly posted his nonsense in a short time on a couple newsgroups I follow. One of them was an electrical engineering forum where westom mischaracterized the views of researcher Arshad Mansoor and provoked a response from an electrical engineer: “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.”

But westom has been posting misinformation about plug-in protectors for ten years? Googling for [“westom” surge] returns about 20,000 hits from an astonishing number of forums. There are more under previous names.

My “half truths” and “lies” are easily found in sources from the IEEE and NIST I posted links to.

Both guides have excellent information on surge protection - much broader than what has come up here.

The lie repeated.

Ironic that westom would quote the “Emerald” book (“IEEE Recommended Practice for Powering and Grounding Sensitive Electronic Equipment”) since the Emerald book explicitly includes plug-in protectors as one of the surge protecting devices.

The 99+% figures for lightning rods and are irrelevant to surge protectors.

And the lie repeated for the third and fourth time.

Is that a violation of the Straight Dope TOS?

Everyone is in favor of earthing electrical systems and we could talk about earthing and single point grounds. But the question is whether plug-in protectors are effective.

Westom has an apparently religious belief (immune from challenge) that surge protection must directly earth a surge. So plug-in protectors, which are not well earthed, can not possibly work. Being evangelical westom googles for “surge” to spread his belief.

Unfortunately for westom, the IEEE surge guide explains (starting page 30) that plug-in protectors do not work primarily by earthing. They work by limiting the voltage from each wire (power and signal) to the ground at the protector. The voltage between the wires going to the protected equipment is safe for the protected equipment. Westom just ignores anything that conflicts with his beliefs about surge protection.

What does the NIST really say about plug-in protectors (surge guide)
They are “the easiest solution”.
And “one effective solution is to have the consumer install” a multiport plug-in protector.

What does the the IEEE really say?
The surge guide has only 2 detailed examples of protection. Both use plug-in protectors. That is after detailed information on plug-in protectors.
The Emerald Book says they are effective.

And all but one of westom’s “responsible” manufacturers say plug-in protectors are effective. (The last one doesn’t say anything.)

Compare that to the sources westom provides that say plug-in protectors are NOT effective. There are none.

26

I do not understand electricity or electrical systems. I do not understand how the appliances in my own house work. However, I have heard the term, ground, since I was young and have come across the verb, “to earth,” and “earthing,” in this thread over an over. But I’ve also read the term, ground, in the same sentence as “earth.” So, I’m wondering if the term “earth” is the newer version of “ground,” and if so, how do they appear in the same sentence? And if not, what’s the difference?

27

There are ground wires in you power system. Ground wires have 2 functions:

1 - provide a way to trip a circuit breaker if there is a short, maybe in a drill you are using.

2 - keep the wiring at a reasonable potential with respect to earth, so the hot and neutral wires do not run at 600V with respect to earth. This includes dumping most surges to earth (some surges are L-L or L-N).

Function #1, contrary to common opinion, does not use a connection to earth (US). The short circuit current is carried on the ground wire to the service where there is a ground-to-neutral connection. From there it goes back to the utility transformer on the service neutral.

Function #2 depends on the connection to earth through earthing electrodes (like “ground rods”).

I find “grounding” confusing because it is often not clear which function you are talking about. Earthing is clear (once you understand the difference). The National Electrical Code is being edited to make it clearer which grounding function is relevant (but the NEC does not use “earthing”.)

“Earthing” is a specific kind of “grounding”. You can replace “earthing” with “grounding” if that helps.

28

Ground is a generic term for the common point. Many grounds exist including moatherboard ground, wall receptacle safety ground, floating ground inside a TV, analog and digital ground, a ground on many telephone poles, lightning rood ground, chassic ground, and a building’s earth ground. Some are interconnected. But all are electrically different.

House has two grounds that meet in a bus bar inside the breaker box - safety ground and earth ground. That three light tester will only report on the safety ground. It cannot report on the earth ground.

Earth ground is required by code for human safety. Earth ground also performs surge protection for transistor safety. But only if that earth ground wire (a bare copper wire that connects the breaker box typically to a ten foot long earth ground rod) is short, has no bends and other requirements. For human safety, that earth ground must meet code requirements (as defined by the National Electrical code). For transistor safety, the ‘whole house’ protector needs that same earth ground wire to exceed code requirements.

A properly earthed ‘whole house’ protector does the same appliance protection no matter if the house has two wire receptacles (no safety ground) or three wire receptacles (has a safety ground). The safety ground (that can be tested by a three light tester) is irrelevant. Relevant is how the ‘whole house’ protector connects to earth ground.

Also irrelevant are the many other ground including floating ground, motherboard ground, chassis ground, etc. Transistor safety is always about how a surge connects (as short as possible) to earth ground - that electrode.

29

i did have an inexpensive surge protecting power strip smoke. smoke did come out. sizzling noise was heard. there was a persistent stink of burnt material (similar but worse than plastic or enamel). there was molten material under the burnt MOV.

there was no other unusual event that i can recall now decades later.

30

there are whole house surge protectors that you mount at your service entrance. there are sections in the enclosure to run phone and coax through.

31

The best protection for cable is a wire that connects low impedance (ie ‘less than 10 feet’) from the cable to the single point earth ground. The same earth electrode also used by AC electric.

Many protection systems have no protectors. But in every case, there is always an earth ground. Cable needs no protector since a wire to earth is the best protection.

Telephone wires cannot connect directly to earth. So telcos have always installed a ‘whole house’ protector where their wires meet yours (often inside the NID) - for free. If that protector also is properly earthed to the same electrode, then phones already have a superior ‘whole house’ protection. As required by code, FCC, Bellcore standards and many others.

Concern is the most common source of destructive surges - AC electric. That utility is not required to have protection. Is only properly earthed IF the homeowner implements that properly earthed protection.

32

Another important part of surge protection is a “single point ground”. There should be entry protectors for phone, cable, antenna, and other wires entering the house. These entry protectors should connect with a short wire to a common connection point on the power earthing system. In the event of a strong surge current to the earthing system, the house “ground” can rise thousands of volts above ‘absolute’ earth potential. Much of the protection is that all wires - power, phone, cable, … - rise together. That takes a short connecting wire from entry protectors to the earthing system to minimize the voltage between power and signal wires.

That is covered in both the IEEE and NIST surge guides.

Running phone and coax wires through a service panel protector, as in the quote above, eliminates damaging voltage between power/phone/cable for surges coming in on those wires. It is particularly good if phone or cable entry is distant from the power service.

“Needs no protector”? The usual installation is just a “ground block” so the coax shield can be earthed. The IEEE surge guide says “there is no requirement to limit the voltage developed between the core and the [shield]. … The only voltage limit is the breakdown of the F connectors, typically ~2–4 kV.” And “there is obviously the possibility of damage to TV tuners and cable modems from the very high voltages that can be developed, especially from nearby lightning.”
Comment to CC
The NIST surge guide, in my first post, is aimed at the general public and is easy to understood. It has good information on surge protection.

33

external antennas should run to a grounding rod, with protection for both leads, before it enters the building. this grounding rod should be bonded to the power grounding rod(s).

34

What should you do when your antenna is at the opposite side of your house from the power entrance?

35

you put an antenna grounding rod at the shortest distance from the antenna.

connect the antenna grounding rod to your service entrance (power grounding rod using 6 AWG wire.

36

Unless you expect the antenna to be struck by lightning the best is to have all external wiring - power, cable, phone, antenna - enter the house at about the same location and have entry protectors on all the signal conductors that tie with short wires to a single point ground on the power earthing system.

If you have distant ground rods there can be a difference of thousands of volts between the house earthing system and the distant rod in the event of a strong surge earthed by the power earthing system. The same thing can happen with a near strike, like to a tree. The thousands of volts appears at anything connected to power and antenna wires. The #6 bond wire is not as effective as you expect because short duration surge currents have high frequency components and the inductance of the wire is much more important than the resistance. Increasing the wire size decreases the resistance but has much less effect on the inductance.

A similar effect is in the IEEE surge guide, page 34, for pad mounted air conditioning compressors.

I am not a fan of distant ground rods. They can increase the probability of surge damage.

Actually, this is where a second protector at the power service can be a good idea, like the phone/coax protector added to a whole house protector - described in one of your posts.

Most of our antennas are not likely to be hit by lightning. If it is likely to be hit the single point ground above is still the best.

An electrical inspector has a weather station that is on a metal post with the post tied to the power earthing system . It has been hit by lightning twice. Minimal damage on the first hit and with fairly minor added protection he had no damage on the second hit. The weather system has a data lead that comes down the pole.

A ham with a high antenna is likely to have a single point ground with better intersystem bonding and a better earthing system.

If the antenna is likely to be hit and the entry point is distant from the power service a ham would put protection on all wires entering the radio area tied to a single point ground where the antenna enters. Protection includes surge protection of power, phone, antenna and any other wires that enter the radio area. For coax, the center conductor is also surge protected.

A strong ‘event’ will lift the potential of the building “ground”. You want all wires to rise together.

If lightning hits a TV antenna on your roof you have a good chance of side flashes into the house from the antenna or coax. It is likely worse with a distant ground rod. If you expect a lightning strike to your house you need lightning rods for protection.