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Ask Slashdot: Best Option For Heavy-Duty, Full-Home Surge Protection?
First time accepted submitter kmoser writes "Like most people, I have a couple of surge protectors for sensitive/important electronics, and even a UPS for a couple of items like computers. But I don't have surge protector on all outlets, and these consumer-grade devices don't cover things like 220 volt appliances. Add to that the fact that I live in a lightning-prone area and it's only a matter of time before one of my expensive devices has a major meltdown. I've looked into full-home surge protectors that install next to the fuse box but the prices vary widely and I have no idea how reliable they are or what brands are good. An electrician friend tells me they can still blow out, and when they do they're difficult to replace if they were installed behind a wall. Can anybody shed some light on the best options for protecting all the electronics in my house with a single surge protector?"
" protecting all the electronics in my house with a single surge protector?" That's going to be a lot of extension cords
Replace it with a nail.
So here is a non answer to your question: Just replace stuff when they break Put your surge protectors next to the expensive stuff and gets some insurance. Replace things when they break. Unless your dealing with medical equipment or servers don't bother with some expensive custom solution.
http://www.dehn.de/pdf/blitzplaner/BBP_2007_E_complete.pdf
The cost of a whole home UPS/surge protectors is going to be rather more than the equipment it protects. Protect sensitive electronics. If you are rural consider burying the electrical lines from property line to the house.
I would encourage use of surge suppressors and UPS systems local to each unit that needs them. These are mass produced, cheap to replace and often even come with offers of an 'insurance policy/guarantee' built in for the value of your home electronics if they do get fried (e.g. the device fails). UPS where continuous power is required, or controlled shutdowns prefered.
Many small, cheap, easy to replace by YOU devices are FAR FAR superior to a single unit you pay too much for and then have to have a professional install.
My 2 cents.
A computer geek since 1980.
That's the 'key phrase' to use when talking to folks, "Transient Surge Protection". Covers everything from the neighbors 220v welder switching on to an induced over voltage from a near hit 1/4 mile away or so.
There isn't a simple "plug 'n play" solution. For example, Motorola's R-56 communications site standard is some 500 pages of how to do this. It takes intentional planning and a bit of engineering as there are at least 2, if not more goals to consider. NEC and local codes come into play as well.
It's not a trivial task. It won't tolerate a trivial solution. Expect to spend some time and money to do it right or risk not only a false sense of security but the chance of making things worse.
links:
http://www.radioandtrunking.com/downloads/motorola/R56_2005_manual.pdf
I highly recommend you check out Raycap products (http://www.raycapsurgeprotection.com/), they're widely used in the Telecom industry and I use then in all my DataCenters.
If you are that concerned about blowing out one of your appliance, I would suggest looking into a home warrenty. They will cover replacement/repairs costs for random appliances along with a number of other things home owners doesn't cover. When I bought my house it came with one and when my dishwasher failed they replaced it, no questions asked. You will still have the inconvience of being without the appliance for however long it takes you to replace it, but you won't be out the money.
I live in a lightning-prone area, but never taken a hit. it's a gamble, but that's what insurance is for to begin with. sounds like you already have all you need, why spend more money to protect appliances unless they can't be replaced? whatever your deductible is has got to be cheaper than the type of solution you're looking for.
Any electrician will tell you that whole house surge protection does not replace local surge protection. It stops most of the spike but not all of it. You still have to have surge protection strips locally for sensitive equipment.
Honestly, how important are surge protectors? Don't most have a disclaimer that they don't protect vs lightning anyway?
I'm sure for large businesses or extreme cost equipment they are a good investment, but for home users are they really needed?
(Honest question since I don't really know)
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
The keyword you used is overload. Breakers prevent against high LOAD. A surge is not load, it is a momentary, sometimes only milliseconds, spike in line voltage that cruises right on through a circuit breaker like it's not even there.
You're confusing current and voltage. Fuses and breakers are over-current devices, Transient Surge Suppressors are over-voltage devices. A high voltage at low amps can destroy all the electronics in the house without tripping a breaker or burning a fuse. The only thing that over-current devices protect against are short circuits in devices or in wiring, or excessive load that might overheat wiring.
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Seriously, finding a single phase SPD to protect your house is expensive. And if they take a direct strike, they'll blow out and need to be replaced (also expensive). Your best bet would be to install some lightning protection air terminals on the roof of your house, and run some down conductors to ground rods. This'll be expensive too, but there's less of a chance of needing a replacement. If you really want to go the SPD route, Siemens has some good products.
Honestly, I wouldn't do either. I'd put some surge protectors on my most expensive electronics and just go through the process of unplugging things when a big storm comes up. If that isn't an option, then be prepared to spend money.
I have a surge protector connected to my power meter and the power company even guarantees your appliances against surges. Here is a link to FPL's "SurgeShield"
Errrr - no. Lightning strikes nearby are nothing at all like the normal, slow over-current events that fuses and/or breakers are designed to handle. I've seen panels completely melted. Of course, at that point, every electronic device and quite a few appliances had already absorbed some much energy that they were equally fried. Like STDs and AIDS, there is good protection available, just not perfect.
When I had my house converted to circuit breakers, it was less than $100 for them to add the whole-house surge, but the electrician was already there for the panel replacement. The whole job was only $700, but that was a good decade or so ago.
It just slots into two of the circuit breaker spaces, so I'm assuming it's just open the panel cover and swap 'em out should something go wrong. (mind you, he also drove in a couple of new grounding rods outside, and connected it all up, so the installation was a little more than just slotting them in)
Whole house brownouts on the other hand ... that's something I've still got issues with, but I'm not willing to put up the money for a giant flywheel.
Build it, and they will come^Hplain.
Effective lightning protection is layered. The socket surge protectors are actually meant to be used in combination with the other layers, not standalone. A close enough lightning strike will induce strong currents in the wiring between the fuse box and your appliances. The surge protectors are designed to protect against the resulting voltage and not much more, and obviously a central surge protector can not protect your appliances if it's not between the surge and the appliance. Stronger surges from lightning strikes into the power lines outside your house on the other hand will not be stopped by the small surge protectors alone. You need both. And then you'll also want a lightning rod to prevent direct strikes into your wiring, because no surge protector would be able to handle a direct strike.
We've got an observatory on a hill with air cabling and plenty of lightning. Our three-stage
protection has never failed through the power line. DSL connections have died many times through the
telephone lines.
First line of defence are large MOV devices with separate grounding installed at the nearest pole. Cost about 600USD.
Second line is at the breaked boxes, cost 400 USD.
Third line is done with 'normal' plug-level protectors for the most sensitive equipment.
Google for Phoenix Contact surge protection..
Here is an excellent panel mounted surge suppressor. http://ep2000.com/index.php?page=industrial
It isn't cheap (several hundred dollars IIRC) but excellent quality.
Do you have lightning rod(s) installed nearby? If not, they can obviously help a lot.
Since all of the appliances in my house are electric (including stove and dryer), I chose this route. It can be wired into any brand of panel not just the manufacturers.
http://www.eaton.com/Electrical/USA/ProductsandServices/Residential/SurgeProtection/WholeHome/index.htm
Along with device specific surge protectors (read: power strips) at more sensitive devices.
Portable nuclear reactors are cost efficient and you never have to argue with your power company again!
My house was hit by lightning. Direct strike to the roof started a fire, was out for 5 months during repair. Here's a rundown of my electronics:
ThinkPad with charger plugged in one room away - charger fried, TP ok.
Audio rack one floor below hit - all plugged in to one surge protector (consumer grade). Five pieces of electronics: top, middle and bottom fried; other two work fine.
Desktop on same level - PS and motherboard fried, drives OK.
Electric oven and stove - fried
ThinkPad with charger plugged in two floors down (in the basement) - charger fine, TP fried.
Tower PC in basement - PS and motherboard fried, drives OK.
Desktop PC in basement - PS and motherboard fried, drives OK
AV gear in basement - projector fried, receiver fried, DVD player OK.
Network gear in the basement (cable modem, router, wifi) all OK
All PCs were connected to UPS systems.
Bottom line, lightning is nasty and fickle. I lost all of my PCs and none of my drives. Surge protectors didn't seem to do much good.
The good news is my insurance waived the deductible since the claim was over $50K, and they replaced all electronics with equivalent brand new equipment.
Make sure you have good insurance and good luck.
Reminds me of an old Dan's Data http://www.dansdata.com/gz039.htm. At some point he discusses ferroresonant power conditioners. Presumably one can get a whole house version. Warning: I am operating from memory, I didn't actually read the article again.
20 characters max for the password? How will I use my favorite poems as passwords?
The standard /. car analogy is 50K people die in car accidents annually, its illegal to drive without seatbelts, therefore seatbelts are a waste of money.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
If lightning is your worry, have you thought about installing a lightning rod?
Find out if the company that manufactures your breaker panel sells one that fits right inside the box. I have one that simply snaps into spot where 2 breakers would normally go and has a wire from there that connects to the grounding system. It was easy to install and I have not noticed any issues sence, that said I do also keep surge strips/UPS's on my important electronics for extra safety.
A strike on your house itself will have an unpredictable path and could easily bypass the single point of protection. Goodbye refrigerator.
Protecting against surges (Transients) and Lightning strikes are 2 very different things. I have worked in some of the nicest tier IV data centers with state of the art redundant power systems and protection. Most Tier IV data centers will have a "Lightning Detection" system. They will count on their power systems and grounding to help, but still track area lightning strikes and be on alert to check things should lightning hit them or close to them. The reason is because there is not gaurantee's when it comes to lightning. That much energy can jump gaps in blown breakers, fuses, and circuits and cause all sorts of havoc, even if the Generator and UPS is still up. Now, transient surge suppression is a different issue and not too expensive for whole home systems IMO. It is not a guarantee, but it is better than nothing at all. http://www.apc.com/products/family/index.cfm?id=174 (this is link to APC residential hard wire panel mount surge suppression options at list cost). Couple a home solution like the APC units above that protects all the random outlets in your house, with strategically placed UPS systems (behind entertainment center, in the office, etc.) and you are getting a decent ammount of protection from the normal surges and near strikes. In closing, lightning is a odd thing. I have been in a house and care that where "stuck". In the car, almost everything was fine, radio lost its pre-sets and time, etc. but that was about it. I don't remember even having any fuses go out. In the house, some things where fried, others where fine. For example, my roommates TV was toast, but the main one in the living room was OK, neither where on UPS. The cordless phone was fine, but the speakers in the corded handset where toast and would only squeal when you turned on the phone.
A LED drawing 1-2W would blind you.
...the variety that supplies power not from the line (which is random and sporadic at the best of times, *often* spiking over 1200v here), but from the battery via a complex circuit which ends up supplying a very clean 50Hz signal at 220v while being continuously charged from the main. So what we have basically is:
dirty line 220-1200vac->isolator step-down to 13.5vac->regulator to 12vdc->battery stack->isolator step-up to 240v->regulator to 220vac->terminal
Works very well, I have a 15-minute grace in the event of a power loss and there's a small computer attached via the RS232 port to signal the workhorses to perform a clean shutdown if the power goes. The same monitor system (a laptop with an internal battery good for nearly two hours) also has the capability to power up the workhorses when power is restored.
Electronic protection and SOHO system automation rolled into one!
Operation Guillotine is in effect.
Protecting an entire building from lightning is a solved problem. You need a lightning rod.
My aunt and uncle live in a hundred year old farm house. It has a lightning rod. Their butter churn has never had to be replaced due to a blown circuit.
There are lots of wire-into-box options like this:
http://www.smarthome.com/48390/Whole-Home-Service-Entrance-Surge-Protector/p.aspx
I have one of these:
http://www.smarthome.com/4872/Phone-Coax-Surge-Protector-IG1300-4T-2C/p.aspx
It was easy to install and my roof-top antenna, cable modem and home power all run through it
Not at all. Parent post suggested a second option: Insurance. One option is to try to make sure nothing ever fails. The second option is to assume that things will fail, and have a recovery plan. This is a vaild suggestion.
The power company where I live charges an extra five dollars per month to install one directly on your meter. This is a great option for me as I am a renter and did not feel like investing money in my landlords property. It took them all of five minutes to install it, so I assume replacing it would be just as fast if it blew. To install it, they basically took the meter off, put a plate that fit into the same space as the meter in, and then connected the meter to that plate. The plate had the surge protector in it.
When I lived in Pensacola, FL the local power company offered a whole house surge protection service/product.
I really shouldn't have used someone else's email address for this account.
Another thing to consider: will your "whole house" surge protector protect you from internal surges?
The only surge that I have ever had blow out electronic equipment in my home was caused internally by an electrician who was supposedly fixing my wiring, not by an external lightning strike.
Also, don't forget other sources into the house - cable, POTS, others.
And let me fuck your wife and any daugheters. And your grandmother. I kindda like your aunt too.
That's how all of IT marketing works, after all
Hmm...learn something new every day.
Is it just my observation, or are there way too many stupid people in the world?
Or just get some shipped over from UK. All surge protection devices (strips, pass-through sockets, etc.) are rated at least 250VAC / 13A with response times for some in the nanoseconds. You'll need plug adapters by the crate though...
"Wait. Something's happening. It's opening up! My God, it's full of apricots!"
A whole house surge protector is not expensive, and easy to install. They simply mount to the main box and connect to the mains, either through a circuit breaker or where the main line connects to the panel. Trivial through the (double/240V) breaker. It can be connected in parallel with your heaviest 240V appliance if no empty breaker location are available, but this means that on those rare times that breaker is turned off it will not be functioning. Better to use a moderately high amp dedicated breaker. Most such will not trip in the time frame of a surge.
After this install, still apply decent quality dedicated protectors to expensive electronics. Don't worry so much about fridges & the like
I think he wanted experienced, hobbyist advice. Or even a bit of professional advice, considering the large number of electricians around here.
Your reply suggests that the only thing preventing him knowing how to perfectly secure his electrical possessions is that he can't spell "surge", or doesn't know of this google thing.
Buzz off. Anyone can google for a product. The question wasn't "are there surge protectors designed to protect a home", but "what are my options? what works well? can I trust a single device to do all I need it to?"
You gave us a comparative shopping list. Brilliant.
Have they finally demoted the USA out of the first world? About damn time...
Signed,
A Disgruntled Florida Resident.
Rather than Google "whole house surge protection" and read through many advertisements masquerading as facts, can someone just tell me the true purpose of whole house surge protection? If you still need local surge protectors, what is the whole house unit doing? Taking more of the blow from large spikes like lightning? Do they help keep a house from exploding? (I'm asking because I don't know. While my post won't help subby, I'm hoping good responses to this question may help lots of people.)
Fuse box = old style of overcurrent protection
Breaker panel = newer style of overcurrent protection
Neither will suppress a power surge, not to mention the fact that having both would be a violation of electrical code.
Speaking of licensed electricians, leave the advice to us, because you don't have a single clue what you're talking about.
Unfortunately, "less than 0.05% of power related events that damage electronics are caused by voltage surges and spikes"
Source:
http://www.edn.com/article/520399-Circuit_protection_basics_Part_1_Issues_and_design_solutions.php
The entire article is worth reading. Can't say the same thing for part 2 of the article, which is basically just marketing hype for the supposed "solution" to these problems.
Exactly. In fact, in some courses (sigh...flame suit on...MBA classes, specifically), you are taught to always consider not only a few viable and different options, but also the "do-nothing" option. Evaluate what happens if questioner does nothing, i.e. stays with the status quo.
Sometimes people come up with all kinds of extravagant and ridiculous schemes and never stop to consider "well, I know my boss said 'do something', but what would be the consequences if we left things as they are?". The answer may not be palatable to the person with the bucks, but then again the do-nothing approach could turn out to be the best option.
I know MBA courses are not the sole preserve of such wisdom, but that's where I had it drummed into me (possibly in an effort to try and avoid the kinds of expensive mistakes that make people sneer at MBAs). First option in your list - do nothing, stay with what you have now. Expenses, risks, benefits.
You're looking for something like the Leviton 57xxx series TVSS, which provides 3-phase WYE protection for all phases to ground, all phases to common/neutral, and common to ground. It's designed to handle extreme events like a close lightning strike or loss of phase. It's got field-replaceable modules so you can replace them if they blow their fuses or MOVs without needing an electrician.
It gets installed between your house power feed and your primary distribution breaker panel. (If you have a primary disconnect switch, it would go there, otherwise you can get a variant of this with an integral disconnection switch.)
http://www.leviton.com/OA_HTML/ibcGetAttachment.jsp?cItemId=RznMfhyJTAUscMgiwmzsgA&label=IBE&appName=IBE&minisite=10251
You'd be looking at a cost of about $4000 including installation.
I used one in a small datacenter in front of a 20kVA Powerware 9330 UPS.
"The human race's favorite method for being in control of the facts is to ignore them." -Celia Green
You may as well save your money because that $200 whole house surge protector isn't going to protect you from a lightning strike any better than a good quality surge protecting power strip.
Just use surge protectors where needed that have an equipment replacement guarantee - and make sure you're protecting phone lines, TV cables, etc too, not just power.
If you have something truly expensive to protect, use an online ups (not line interactive) for more isolation - a lightning strike might take out your UPS, but is less likely to reach your computer (but if it's a nearby strike, all bets are off since even your ground can be a path for a power surge).
Or, just throw caution to the wind - I spent 10 years in a lightning prone area, and never used a surge protector at all -- lightning made the lights flicker many times, but I never lost a computer, TV, or stereo (or any other device) to a lightning strike. On the other hand, I saw the aftermath of a nearby strike on a friends house - lightning hit a nearby power pole, and he said he saw sparks shooting from his outlets. He did lose his TV and stereo (which were both plugged in but powered off by a physical switch at the time).
clicking your link yields zero results for me.
Whole-house surge protectors run $40-60 at Lowes and Home Depot (Siemans/SquareD), but you're best to get an electrician to install them because they need to be installed in the breaker box. One type is a double-breaker and clamps into the A & B busses with a wire to ground. The other has three wires to the same places.
IMHO whole-house is _much_ better than power-strip MOVs because of the reduced impedence to ground -- the rod is near the box. Also, check your ground rod and upgrade clamps -- they often deteriorate (loosen or corrode).
Make sure phone & cable TV entrances are also grounded, preferably to the same stake. If they are on opposite sides of [old] houses, you are going to occasionally fry equipment from nearby lightening strikes due to transient ground potential difference.
I guess these must illuminate with the same luminescence as the sun at their ultra high 13 watts?
http://www.homedepot.com/h_d1/N-5yc1v/R-202668646/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=LED+lightbulbs&storeId=10051
In my experience, getting a good ground is sometimes the toughest part of home electrical upgrades, period!
Twice in a row now, I'm moved into homes that were built in the 1950's or 1960's, and didn't even provide 3 prong grounded wall outlets.
In both cases, I tried to hire an electrician to upgrade my home to properly grounded outlets, and after they did a few basic tests, essentially told me they weren't willign to go through the trouble it would take to do it. (Basically, they decided the only good way to accomplish it involved sinking a rod into the ground outside and wiring the main buss to it with an underground cable.) Either they were too lazy to do it, or simply thought it would take too much of their time to be able to quote me anything like a reasonable price for the project.
We have a uk house earthed with a modernish electrical trip box of ten year - anything internal like a light-bulb going can trip the local circuit and not the house. The item is not up to date with modern building rules and regs,
Poe devices (ethernet over electrical wiring) are ok with this
UK electrics items are also fused, although having lived in Germany i have bought a large flat fuse when the power died,
The underground power mains from the power supplier most summers terminates though old age and the three phase box is replaced, when this happens the surge is not tripped.
Natural lighting strikes is something i have no experience of and if it has happened being earthed seems to dealt with it
You can buy good lightning protection devices from Square D or Siemens. Here's a background paper from Siemens. and a product guide from Square D.. These go between the meter and the circuit breaker box. They're hulking big metal boxes with big inductors inside and a huge ground wire. You can get various peak current ratings, up to 480,000 amps. That's more power than lightning bolts have.
Similar protection devices are available for phone lines. These attach where the phone line enters the building and, of course, have a big ground wire.
This is a completely solved problem. Antenna towers, power lines, and telegraph lines have been taking direct lightning hits for over a century, and the protection devices are available. They're not even all that expensive. Just big.
A good solution would be to do with "Total Protection Solutions". They have a warranty of 20+ years and their product is really robust. It could probably do what you are looking for, though, they are not cheap.
http://www.tpscanada.ca/
You have to remember that the more MOVs you have, the better chance you have to absorb a lightning strike.
Not true, just like AIDS and other STDs, there most certainly is a perfect protection available....its just that most people don't like sitting in the dark with all of their electronics unplugged, especially if they aren't getting laid either.
Of course, in either case, this solution is not considered fun.
"I opened my eyes, and everything went dark again"
Yup. Because one case where the do-nothing option isn't the best one means that it's always a bad option.
Have an electrician install a whole house surge device at the main power panel. Remember, these protection devices are designed to fail after a BAD hit. Get a surge device with external status display.
I installed mine, I do not recommend you install this as you need to pull your meter and most (all) power companies don't like this. Especially, when amateurs are doing the work. Oh well.
We use suppressors from Transtector on the AC lines, and suppressors from PolyPhaser on RF lines at a number of radio tower sites my employer owns. No lightning damage in the time I've been here, just have had to replace a few PolyPhasers, which means they work.
Also you really, really, really need a good, low resistance earth ground. Bond EVERYTHING to it.
If the *actual* problem is surges due to your house being struck with lightning, a full house surge suppression unit will do NOTHING for you. The way surge suppressors work, is when the current/voltage spikes very high on the input, it grounds the line to dump the excess.
To better visualize:
Line in -> Breaker -> House -> Outlet -> Device
In a situation with a suppressor at the breaker, you would have this:
Line in -> Suppressor -> Breaker -> House -> Outlet
Such a setup would NOT protect you from a lightning strike, which is:
Lightning -> House -> Outlet -> Device
The only way to protect your devices from death due to lightning strike is to put a supressor between the outlet and the device:
Lightning -> House -> Outlet -> Suppressor -> Device
I find a good low cost option is to stick a Line Conditioner on each outlet that's sized for the devices that will plug into it. So my computer has an 1800W Line Conditioner, while my receiver and TV only have a 600W Line Conditioner. It'll only run a few hundred bucks to protect all the appliances you are interested in saving from lightning.
As mentioned by everyone else, if it's not life ending, insure it and just replace.
http://www.google.com/products/catalog?q=whole+house+surge+protector&um=1&ie=UTF-8&tbm=shop&cid=2095718605650227831&sa=X&ei=_syqT7vTOKm62wWN7eymAg&ved=0CPcBEPMCMAE
That is one of the best made. If you want to waste more money, look at the snake oil sold by http://www.richardgrayspowercompany.com/
Nothing is better than the above Leviton unit for surge protection.
Do not look at laser with remaining good eye.
Just keep in mind that you still need to protect phone/cable lines as well, but i think it's a good idea, if your utility offers it.
"Anyone who trades liberty for security deserves neither liberty nor security" --Benjamin Franklin
I live on the US Gulf Coast and I get more than my fair share of lightning strikes. Because of the long power feed line coming to my house, the power company installed an "enhanced" ground system and whole house surge suppressor. While I haven't had a lightening strike take out all my electrical appliances, I still have the occasional small electronics die during an electrical storm. My cable modem, television, and anything connected to coaxial cable have been struck by lightning so don't forget to purchase lightening protection for your coax. I used to use a brand called transi-trap during my amateur radio days, but I'm sure you can find something comparable at your local hardware store.
Anyway, I have very tall pine trees that act as natural lightning rods. When one of those get hit, anything near that side of the house is pretty much hosed. So be aware that despite your best efforts, you may still get equipment failures. Ultimately this is why I have insurance.
You may want to consider removing any tall trees near your house. Unless you're like me and think the shade provided by the trees is worth more than the chance of getting hit by lightning (e.g. the increased cost of cooling versus the probability of replacing some equipment).
These comments are my own and do not necessarily reflect the views or opinions of my employer or colleagues...
Most of the surge damage I have seen in the last several years is on things like phone lines and Ethernet. Long wires act like antennas and get high voltages induced onto them. Ethernet is especially sensitive. Surge protectors should located as close as possible to equipment being protected for maximum protection. Over the last several years I have lost more Ethernet ports on switches and equipment than anything else. Good Ethernet surge protectors at http://www.magicsurge.com/
Insurance works once. After you file a claim your policy is cancelled or your rates become equal to the value of your claim and they exclude coverage on the risk you filed a claim on. The insurance companies share claim histories too so forget switching to a different company.
Better to have some loss mitigation tech in place in addition to insurance. You might get a break on rates too.
I have a whole home surge protector. Fits above the mains panel.
30 minute installation by an electrician and works nicely.
http://www.purgethesurge.ca/docs/SPD4home.pdf
has two nice lights to show its functioning normally and works great.
All you know is that it passes your mains voltage and lights up your little blinkies. You need to conjure the ghost of Nicoli Tesla and create a giant electromagnetic storm over your house and see if your system survives that.
Only then can you be sure.
Faster! Faster! Faster would be better!
Effective lightning protection is layered. One of the best things you can do to stop errant radio waves from messing with you is to build a Faraday cage around your house. That will provide an effective defense against lightning strikes from outside the home.
However, this won't protect you from lightning strikes that occur INSIDE the Faraday cage. To defend against that, you need to not only have everything inside a Faraday cage, with a household surge suppressor, you also need to have a separate Faraday cage around every electronic device in the home, each with its own surge suppressor. It may seem a bit awkward, having to crawl inside a cage to watch TV or play computer, but it's worth it!
That way, when the aliens attack with their pulse EMP weapons, you will be blithely unaffected and will be able to sell your stereo on Ebay when everybody else's has been blown to 5h17.
Seriously, why is this important? If you care about your device, get a $10 surge suppressing power strip and call it good. I've already had several devices saved by such devices, when my parent's house was hit by lightning, it blew out their TV/VCR, microwave, telephone, and just about everything else in the house, except for the computer that I'd insisted they buy a SS power strip for.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Just call your power company, many offer whole house protection for an additional monthly charge and insure against any problems.
For example, my power company is Gulf Power: http://www.gulfpower.com/premiumsurge/home.asp
That's fine and all, but those are LED LASERS, not LED lights, the post he was referring to was talking about an LED light. LED lights are up to 23 watts being the same as an incandescent being 100 watts (REF: http://news.slashdot.org/story/12/05/07/193200/philips-releases-100w-equivalent-led-bulb-runs-on-just-23-watts?utm_source=rss1.0moreanon&utm_medium=feed )
LED lasers like all lasers at a much lower power rate are hazardous due to the radiation aspect of it (Light Amplification from Simulated Emission of Radiation)
There are normal, fuse-like surge protectors you can just install in the breaker-board. If you are paranoid, you can use MOX and plasma devices at once. I do not know what standards are in use at your side, but here are a few links for 235V devoices used in Europe (sorry, text is German):
https://www.distrelec.ch/überspannungsableiter-typ-1-dreiphasig-für-tnc-systeme/dehn/dv-m-tnc-255
https://www.distrelec.ch/überspannungsableiter-typ-2/dehn/dreiphasig-für-tt-und-tn-systeme
https://www.distrelec.ch/überspannungsableiter-typ-3/phoenix-contact/für-netzspannung-einphasig
Prices for material are about 150USD for 3 phases, so not really expensive. You cannot really install these yourself though, but every licensed electrician should be able to install them. Basically it is like installing an additional circuit breaker between the main fuse and the individual fuses.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Or you could use "reverse insurance". That is instead of making payments ahead of time and claiming the value of the item if it fails, you wait until it fails then buy the replacement on credit and make payments over time until it's payed off.
False: a close enough strike will induce currents in things that are unplugged. This is especially bad if the things that are unplugged are feedlines to antennae, but it can happen with any metal object, given a sufficiently close strike.
As others have mentioned, I would as your local power company, our local provider (Duke Energy) offers something called StrikeStop (http://www.duke-energy.com/strikestop/) which offers whole-house protection (and they install it on the power meter, which is a nice bonus) at ~160$ installed it was a no-brainer decision for me considering it offers insurance along with it.
Years ago I had a lightening strike on the cable TV lead in. It melted about 60 feet of insulation and left the carbon core of the cable hanging naked. Oddly it didn't hurt the cable box or TV at all but somehow went down the electrical wire and knocked out the circuit breaker for the how water heater. Lightning is weird and it is very difficult to predict what may be harmed by a strike.
When lightning struck nearby earlier this week, it induced a current in some twisted-pair Ethernet cables, killing a Linksys switch, a Westell router and an XBox 360. Go ahead and protect your power lines all you want; it may not do any good.
If I used a sig over again, would anyone notice?
Surge protector Fraud Alert: The maximum allowed energy of the $30 surge protector, 560 joules, is tiny. It seems that the manufacturer is taking advantage of the ignorance of most people and Home Depot about electricity.
A joule is 2.78 x 10-4 Watt-Hours of energy. Calculating the maximum energy allowed by the surge protector: 2.78 x 10-4 * 560 = 0.15568 Watt-Hours. That means the surge protector can protect against a 1,000 watt surge for 0.00015568 hours. If I calculated correctly, that is 1,000 watts for 0.560448 seconds. More realistically, a lightning strike would cause at least a 10,000 watt surge. The surge protector could protect against that for 56 milliseconds, a trivial amount of time. I've seen lightning strikes that lasted more than a hundred milliseconds. The current in a 10,000 watt surge at the rated 175 volts is only about 57 amps. If you want to protect against a more realistic 570 amp surge, the protector will last only 5 milliseconds until it explodes.
The surge protector linked may just have 3 small MOVs.
Some surge protectors give no indication or inadequate indication when they have burnt and stopped protecting. The linked description says, "LED indicates operational status". For you to know if the device is working, you must check to see if the LED is lit. That's not convenient if it is installed in "service-entrance locations".
The Home Depot web page to which you linked says,
"36,000 Amp maximum
20,000-volt maximum surge current".
The "maximum surge current" listed is said to be 36,000 amps, but that is for a minuscule amount of time. Volts are not current; saying "20,000-volt maximum surge current" is ignorant.
Translation: The CEO of Home Depot has no technical knowledge and should be replaced immediately. If I were CEO of Home Depot, one of the first things I would do would be to make sure all the descriptions were accurate; I would not allow sneaky, tricky product descriptions.
Ignoring the idiots responding to this...
You're absolutely right. Let's assume an LED running at an 20 ma of current. An LED can't be connected directly across 120V (well, actually it can, and is amusing in a small-firecracker way), so a dropping resistor is used to reduce the current flow through the LED when on to the 20 ma that the LED can take. The combination of the LED+resistor end up with 120V (ignoring half-wave rectification and RMS voltage values) across the pair, and 20 ma going through them, for a combined power of 2.4W.
The LED isn't drawing 2.4w (which, by the way, is a nice bright flashlight), but the lighting SYSTEM is. An 80% off-line switching supply could be built that provided the .06W that the LED is actually using, but your power strip would cost $10 more.
And the worms ate into his brain.
Ground spikes are standard procedure and have been part of building code for decades.
If you can't find an electrician to do it for you, it's not that difficult to do it yourself. Get 2 ea. 6' copper ground spikes from your local hardware or electrical supply store, and pound them in with a sledgehammer. Careful not to bend them too much in the process. They aren't iron.
Then a little bit of bare copper ground line, maybe around 3 to 4 gauge, to each spike.
It's not a difficult job at all unless your house was built on top of a giant rock. I suspect that the real issue was not the ground spike, but running the rest of the ground wires through existing walls. That is the kind of job that no electrician likes to do. When I was looking to buy a home I passed up an otherwise great price on a nice house for exactly the same reason.
Sure, I could have taken the money saved and upgraded the wiring, but it would have been so much of a pain, and caused so much temporary destruction to the interior, I decided it wasn't worth the trouble.
I should add that if you have iron pipes, you can get much of the same protection by grounding to the water pipes at the closest point to where they run underground.
That might not meet code, these days, but it used to for a very long time. And it will give you a serviceable ground.
Don't ground to your gas pipe, though. Not A Good Idea.
present a much more attractive target than the power pole or that big tree on the bedroom side of the house, and your worries are way down. professionally installed lightning rods with big-ass ground leads to a nice multipoint ground is much more attractive, and proven to work well.
if this is supposed to be a new economy, how come they still want my old fashioned money?
With a Sola ferroresonant transformer.
Competition Good, Monopoly Bad.
The very first thing you should do is check your grounding... EVERYTHING is secondary to a good grounding system. Without a ground that does not suck introducing surge supression runs the risk of actually increasing damage to your gear.
Is your grounding rod doing its job? Are all of your outlets grounded? Is EVERYTHING coming into your home grounded? Is there a single grounding path?
Surge supressors are useful for protection against induced currents from nearby strikes, crappy utility power, crummy EMP weapons..etc...they don't do jack diddly squat against lightning strikes. The only form of lightning protection is to offer your thunder god a more appealing path to ground as far away from your stuff as possible.
There are other tricks avaliable for reducing induced current on internal wiring. The best approach is to purchase twisted romex... simply twisting wires reduces induced currents more than anything by a wide margin including expensive steel conduit and assorted shielding.
In Canada at least this does not happen. I've claimed on home insurance twice, both times they simply paid out without hassle and I lost the discount for not having any claims in the past X years.
If you have something truly expensive to protect, use an online ups (not line interactive) for more isolation - a lightning strike might take out your UPS, but is less likely to reach your computer (but if it's a nearby strike, all bets are off since even your ground can be a path for a power surge).
No surge protector will protect against a lightning strike. A UPS might (might) do something if the discharge comes from the electrical grid, but a lighning has high enough voltage that it would arc, go through the UPS casing (if it's not plastic), and then reach your computer by arching more, and jumping through any insulation. Even if it doesn't hit your electronics (ie: if you build a faraday cage around them, for instance), the heat blast will break your computer and anything electronic.
I know, I suffered something far less potent: a medium-voltage line falling on the telephone line, it fried the surge protector, the voltage was high enough to arch through it, broke it in half and went through the modem, arched into the GPU, and then it literally cracked my HD open next. The telephone company took responsability and replaced my computer, but I suspect there was nothing they or I could do. It's just too much power pumped into a grid that wasn't ready to handle that. And we're talking about a mere 35000V.
Lightning? Forget it. You'd lighning-rod-grade ground wiring.
The NEC these days has you drive a 6'-8' ground rod underneath the panel at the service entrance, bonded to the panel. You ALSO have to run bare copper back to the service entrance for water, and bond to that as well. In case one or the other fails, you still have a reliable path to ground. It's not simply a matter of bonding to grounds though. The panel itself needs to include a bus bar for tying all the individual grounds together, and providing a path to both both bonded ground points. So now you're basically looking at a service change, replacing the panel, meter, and mast (if applicable). It's not horribly expensive, but it's not cheap either (I used to do em for around $5k-10$k depending on the job, but that was years ago).
Lightning is weird and it is very difficult to predict what may be harmed by a strike.
Just like my ex-wife!
8 of 13 people found this answer helpful. Did you?
A long time ago, Jerry Pournelle wrote in Byte Magazine to describe his experience with a destructive power event.
As I recall, he wrote that a car struck a power pole somewhere down the road, and dropped the 30,000 volt lines down onto the residential 220 volt lines, resulting in the (normally) 110 volt wiring in his home being briefly charged to 15,000 volts.
He wrote that the lights went out, then came back on REALLY BRIGHT, then went out again and stayed out.
I do not remember all of the details of his equipment, but I do remember that he had a variety of spike and surge suppressors, ranging from a $5 el-cheapo unit up to some fairly expensive protection.
End result: NO piece of equipment that had ANY kind of protection was harmed. The only piece of gear that was hurt (a VCR, I think) was plugged directly into the wall.
My recommendation: put whatever suppression you can comfortably afford on every piece of hardware that is valuable to you. After an "event" of any severity, replace them. For the most part, you have no way to know whether they are still working.
TyZone
and if you do it wrong, your bathroom faucet will shock the shit right out of you!
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
I guess these must illuminate with the same luminescence as the sun at their ultra high 13 watts?
I guess someone doesn't understand how size and intensity are related. I don't know how bright a 2w single LED actually is, so don't take this as defending that statement specifically, but those household lamp units contain dozens of individual LEDs plus their power control circuirty (LEDs don't run on 120VAC you know), adding up to the specified 13w consumption. The intensity of the light is then further reduced by the translucent cover wrapped around them to make them look and cast a light pattern more like an incandescent bulb.
In no way are those comparable to ultra-bright individual LEDs, which are a single small source of light which depending on the LED's shell design may even be focused in a particular direction.
Around 13w worth of light spreading in all directions from about 20 square inches of surface area versus 2w from what appears to the unaided eye to basically be a point source at any notable distance which is then possibly focused in one direction. The 2w bulb will look a shitload more intense if you put them side by side for sure, even though the 13w unit is putting out more light energy overall.
I used to get high on life, but I developed a tolerance. Now I need something stronger.
Our house has a device made by Joslyn labeled "secondary surge suppressor" and "lightning protective device". It simply bolts to the main breaker box, and wires to each main supply line.
If I remember it was rather cheap ($35?). A google search of the model number finds only ebay hits, so apparently superseded.
I believe it is similar in function to this:
http://www.surgepack.com/transtrack-lp.htm
No idea on effectiveness, but perhaps something to research.
The best is when the MBA types decide to do nothing, without bothering to fully evaluate what the true cost of doing nothing is. Then when the reality of doing nothing begins to settle in, it is too late to effectively do something due to insane lead times.
Most equipment in your house can handle minor surges. Furthermore, most of the surges seen in your house will be generated within the house and so this won't stop them.
This would only be useful for massive external surges (i.e lightning), which it is unlikely to stop anyway.
http://lkml.org/lkml/2005/8/20/95
I first laid my sticky hands on a computer in 1978. Since that time, I've heard of exactly one lightning strike that broke stuff: a friend lost a modem on his Mac LCIII in 1992... his computer was surge protected, his telephone line was not.
Screw surge protection. What you want to aim for is uninterruptable power. The surge protection will be included in that, and it will actually be useful a few times while you're alive.
The Admin and the Engineer
150 some posts, and not one mention (from any of them with a score of 2 or higher) mentioned gas-discharge tubes?? Surge protectors will not protect from lightning. No consumer-grade UPS on the market will survive or actually protect from a full-on lightning strike, nor will most consumer-grade "whole-house" systems. The best thing you're likely to find that will ACTUALLY do the job requested is a gas-discharge tube.
"Inveniemus Viam Aut Faciemus" 'We will find a way... Or we will make one!' --Hannibal of Carthage
So that's what Halliburton did wrong in Iraq....
People in cars cause accidents....accidents in cars cause people
Unplug your electronics when there is a storm. Plug your electronics back in when the storm is over. Reset your clocks. Done.
I provided an answer based on my expertise. You are belittling me for even trying and now I'm a troll for offering what little knowledge I have on the subject. sad
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
Not what you think (I can see you sniggering...). My sax teacher had a brown-out, and it jerked his RAID-5 in his PC and fried an external HDD. I got the RAID back, but he's still working on the external - fitting a new actuator (?). A brownout (imho) is a period of extremely low voltage. In his case, caused by some ham-handedness by the power boys working on his street. Both he and I have since bought a UPS for PC equipment where we didn't have it before. Eaton 5110 for me. Dynxmix for him.
... I suspect it'll do its best but no guarantees. Even the guarantee in the equipment probably has a get-out, or a limited liability. Better to light one candle than curse the darkness though ...
Anyhow - (imho) UPS guards against brownouts and surges. Against lightning strikes
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
You are only reinforcing the point I already made: it is not the ground spike that is the major issue here. It is all the other work that is necessary. Also, you are talking about the requirements of code. I specifically stated that a water-pipe-only ground probably does not meet code in most places today.
"and if you do it wrong, your bathroom faucet will shock the shit right out of you!"
That's certainly true. But there are few excuses today for getting it wrong. House wiring is ridiculously simple, if one bothers to learn the basics. I have wired several homes myself. Not genius material at all.
I put a rider on my home insurance policy which covers all my *personal use* electronic equipment. I can't remember how much it is a year, but it's not too much. But - If you use any of the equipment for business you have to get a business equipment policy (homeowners insurance typically won't cover anything used for business). I have about US$25K in various computers, external drives, wireless, (etc., etc.) equipment and my policy is US$220/year. YMMV
BTW - You want to make *sure* it is a *replacement cost* policy or they'll use a formula and pay you the "used" value, so if you have a 5 year old computer (for example) you'll get a fraction of the replacement cost. This is for both home owners and business. A friend had a house fire (aluminum wiring) and (for example) her washer was 9 or 10 years old - They gave her something like US$35 to replace it since she didn't have a *replacement cost* policy.
I'm blowing a couple Mod points but. . . Take a look at www.brickwall.com for surge suppressors. These are not whole house units but they are not damaged by 1000 consecutive surges at the maximum energy at which IEEE tests. They also have panel mounted ones that can be used to protect a whole circuit. They are basically an analog lowpass filter on steroids and as a result suffer no damage from surges that would completely destroy a MOV based surge protector. I've got one on my stereo. I've never looked at the results with an o-scope or anything but the engineering principle on which they are based is sound.
http://www.mikeholt.com/mojonewsarchive/LSP-HTML/HTML/TVSS-Protection-Questions-and-Answers~20040708.php
Those guys know their electricals.
Damage from a close lightning strike will probably not be mitigated by whole house surge suppressors. But I would still install one. The important point to look for is UL 1449-listed devices. Then at specific locations, install a good surge suppressor. Kinda like computer defense-in-depth. Something from ZeroSurge will help if your home is old and doesn't have ground; otherwise, a normal MOV surge suppressor requires good ground. This would be equipment ground and is not the same as your grounding rods/water pipe ground. The latter are really for lightning strikes. ZeroSurge doesn't use MOVs and don't rely on equipment ground. You may also want to consider getting a line conditioner but I haven't done any research on their viability.
I'm looking at the Leviton 51120. Depending if your house is single or three phase, you'll need to get the right model for the type of service you're receiving. The Leviton is nice because it comes with its own J-box for extra protection. Eaton (Cutler-Hammer) has one but it's normally attached on the bottom of the buss bars while a lot of other companies recommend their TVSSes be installed on a breaker that is the closest to the service conductors. I prefer the standalone devices like the Leviton because they could be installed on any panel instead of a specific brand. The Leviton can also pigtail into an existing breaker. If you have Eaton/Square D QO breakers, you could attach up to 2 hots per breaker.
If you do decide to get one installed, make sure you or the electrician make the conductors as short as possible and don't create too sharp a turn in them.
Wrong! If the MOVs burn and become open while the surge continues, both the surge protector and the attached electronics can be destroyed.
Just use surge protectors where needed that have an equipment replacement guarantee - and make sure you're protecting phone lines, TV cables, etc too, not just power.
The problem is surge strips are inconvenient, and you might temporarily plug something in that really should have one, but because surge strips are inconvenient you don't have one on every single outlet..
Surge strips also don't work for hard wired devices -- such as Insteon wall switches, InLineLinc, X10, and other devices that get hardwired, for automatic light control - which are sensitive to overvoltage, and a surge can knock them all out.
This one took a long time for me to track down. I'd put a surge protector on the phone line and the ringing current blocked incoming faxes. When fixing this I was informed that properly installed phone and cable lines should have proper surge protection included.
My house was built in 1953 and had an extension put on in the late 80's.
The extension is wired to code, and at that time the bathrooms and kitchen were mostly upgraded as well.
I inquired about having an electrical refit done and of the three contractors I talked to, two said they wouldn't take the job and the third, a neighbor, said that the reason the others wouldn't even bid the job was that the cheapest solution is actually to pull out the interior walls and re-wire that way. As a bonus he pointed out that once the walls are off it's also possible to wire data, fix questionable pipes, and insulate nearly for free (not because it is cheap, just that pulling walls out and replacing all the Sheetrock is god awfully expensive).
He said the other ways leave people always pissed off, even if cheaper:
* outlets on a wall sill and under a window? pull the outlet and patch the wall, run a new outlet not under the window from the attic. The patch and new outlet both standout as not original.
* Have a wall that's wood veneer and not textured? tough, it can't have a new outlet if there is a window in the way.
* Where are you going to sink the ground rod? out next to the service panel of course, and that's not pretty either.
-nB
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
Something based on an Isolation Transformer would be probably the best thing. You can isolate the surge & clamp it at the source.
You don't install surge protectors to defend against a direct lightning strike --- there is no real defense against a direct lightning strike - you can make it less likely with a well-engineered lightning rod protection system.
You install surge protectors to defend against currents induced by nearby lightning in your wiring. This is protection against damage lightning can cause without actually striking your wiring, or your building. If lightning strikes a mile away from you, and hits the ground, or a tree: this lightning can still induce currents in unshielded underground and overhead power and data cables. If there is no surge protection, the induced currents may destroy sensitive electronics such as computer power supplies.
In a direct hit situation, lightning hitting a surged protected circuit can easily arc through any surge protector; human safety is paramount in the design of surge protection and electrical systems, anyways, so there are always compromises anyways, that is, surge protectors still share a common ground with everything else, and a direct hit clamped to ground can effect everything else tied to that ground --- Remember, with resistors in parallel, the amount of current is proportional to the resistance - the amount of voltage passing through the higher resistance path is not zero. Even if 99.9% of the lightning strike is clamped to ground, the 0.1% can still be 10000 volts.
No commercially available surge protector apparatus able to be fitted to a home electrical system and other utility lines entering a building with a price that is remotely affordable to the average homeowner is capable of providing remotely robust protection against a direct strike.
I was working on a digital copier about 8 years ago that would wig out at odd times. When I put a voltage load monitor on the line, when I would give it a 15amp load, the neutral to ground voltage would jump from .6 to 11volts!
Told the customer to get the ground checked. When back a week later & they said the ground rod
was only TWELVE INCHES long and was only 6" into the ground, which in this part of the country,
is mostly rock. They had a 6' rod placed by a qualified electrician. Never had the problem with the
machine again.
Ground rods do not have the proper impedance required for equipment ground--specifically they could prevent a breaker from tripping which would be a very dangerous situation. Ground rods' high impedance as opposed to a proper grounding conductor is why they are only used to mitigate lightning strikes.
If your house is on a concrete slab it would be quite difficult to rewire anything without tearing up lots of sheetrock or lath and plaster.
Can't be done.
First flaw is most surge suppressors are MOV based (Metal Oxide varistors) that are by definition sacrificial in that each and every surge they stop they burn up a little and there is NO WAY to non-destructively test this in-circuit.
Second flaw is if you truly understand surges, you will know that surges are generated INSIDE as well as OUTSIDE your house. Any inductive load creates a surge.
Third flaw -- conventional surge suppressors simply dump excess energy into ground, good theory except the ground at the outlet is NOT EARTH GROUND - it is earth ground plus the inductance and capacitance of the wire all the way back to the electrical box and the stake into the ground. What this means is with wired network machines on different outlets a surge generated and suppressed on the power line to unit one can actually create a problem for machine 2 on a separate circuit (think in terms of coax and its easier to see - Unit 1 ground potential goes to poss 1200v, ground potential at unit 2 is still at zero since it has its own home run ground back to the box. Now image a coax cable connecting the 2 machine - 1200v on one end 0v on other.)
Its a little more complex than that in detail but this gives you a general idea and its why I use serious unit at each point on my network and my house in over 20yrs and I can only account for 1 surge damaged device (which was inductive damage from a near strike outside the window.)
I started using these unit when I still ran a BBS, even in those days knowing the weakness of MOVs (which I changed every 12 or so months) I still had failures that I knew where surge damage, after moving to the "Zero Surge" units, my failures stopped (For seven yrs I had modem or RS-232 driver circuit failures at least once a year, the last 2 years of running the BBS there were no failures and the ONLY change was the use of the new surge suppression.
I am not employed or associated with "Zero Surge", only a long time loyal customer.
For more information, refer to http://www.zerosurge.com
I should add that if you have iron pipes, you can get much of the same protection by grounding to the water pipes at the closest point to where they run underground.
The important thing is there must be a single ground, and it must be a low-resistance ground (copper wire sized appropriately and attached with the proper UL listed clamp for the application).
If you do have both conductive pipes and a grounding spike, you have two grounding electrodes.
All grounding electrodes that exist must be electrically bonded with your system ground at the main panel.
E.g. you can't have conductive pipes, but fail to have them bonded or connected to anything -- that creates an electrocution hazard, if someone touches a metal object connected to the plumbing and another metal object grounded to the main panel at the same time.
There must be only one ground in a system, and that single ground must be bonded to all grounding electrodes which connect to anything in the building.
And that bonding should occur at the main service panel, which must be the place where Ground and Neutral/Common are also bonded.
Ha. Sometimes you can rightfully blame IT manaagement for that money saving... Long ago (in the days when we worked on 'smart graphics terminals - in fact our company was at the time the largest maker of graphics terminals) I worked in a building with 400 other engineers. We had four mainframe computers (DEC-10 and DEC-20). The engineers, and finally even the marketing folks, lobbied hard to get a motor generator installed to power the computers because of the risk of power failure. But the head of the computer center insisted that it was a waste of $400,000. So, of course, one day lightning struck the power entrance into the building, and completely fried all four mainframes. At least one of them caught fire, so the Halon extinguishing system went off. Every circuit board in all four machines was literally toast. It took a full crew from DEC over a week to get parts in overnight, replace everything and get it working again. So we had 400 engineers playing tiddly-winks for over a week. Then we had to recover from backups, etc. At the time average salary in the building was probably $16/hour for engineers but the fully loaded cost was (benefits, capital amortization, etc.) was over $50. So, 400*$50*40 = at least $800,000 down the tubes.
The manager got 'promoted' - to a desk job with no underlings, and nothing to do. The company was one of those back then that didn't fire people, but they didn't have to use them either.
While we are at it, if the OP really wants to be isolated, a motor generator really is the best way to go. It won't prevent the possibility of getting fried via ground current, but use a motor separated from the generator by a significantly long non-conductive shaft, and you're going to be as safe a feasible.
Also, put up a lightning rod - it should be high enough to provide a 60 degree 'cone' over the house (that's a lot higher than they usually are) with a big, fat (0000 - about 3/4 inch) copper or aluminum cable down into a ground stake that preferably goes deep into damp strata. There is evidence that (on boats at least) that stuff inside that 60 degree cone is fairly well protected from direct hits.
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
You ALSO have to run bare copper back to the service entrance for water, and bond to that as well. In case one or the other fails, you still have a reliable path to ground.
That's not why you have to do it; "grounding" is relative and not a magic thing that guarantees no current will flow, electrical current can flow between "ground" connections. Ground potential varies from place to place, 10 feet away, ground can be at a different potential. Geology, Electromagnetic interference, solar activity, lightning, electrical faults elsewhere, and other factors can further exacerbate the difference.
Bonding is required for the same reason that Neutral and Ground must be connected together at one place (the main service panel). If you do not have Plumbing Ground and Electrical ground bonded, you have different parts of your system connected to ground at different places ---- this means, the ground on your service panel can now be at a different electrical potential than your plumbing.
What this means, is that if something conductive touches both your plumbing, and something connected to the main panel ground (or neutral), current will flow through that conductive thing, to equalize the potential of the different grounds.
If that conductive thing is a human, this could very well mean that someone dies, because they touched the tap electrically connected to the plumbing, and a kitchen appliance with a metal chassis connected to neutral.
Therefore, the requirement is that you already have these bonded together with a low resistance path.. The bonding ensures that both systems are always at the same potential, so current does not flow between Neutral or Main panel ground and your plumbing.
Your MBA training is obvious. Had you pursued an engineering degree, you would have had to do a certain amount of lab time. Lab time gives you the practical knowledge that the do nothing option is purposely placed last on the list. This gives the MBA managers the requisite number of meetings to discuss all other options and keeps them out of our hair .
Are you saying that at Home Depot no one in top management has control over dishonest descriptions of products?
That description of the surge protector was, in effect, an advertisement for Lowe's, a competitor. I don't want to waste time with companies I can't trust.
Not an electrician, but I thought a Ufer ground was basically required by NEC these days(??). Basically, just put it in the foundation footer, or slab for slab-on-grade, and you've got a really good local ground for the house (concrete is a pretty good conductor, relative to dirt). Making sure all the utilities enter the building in roughly the same area, all with short-as-possible low-resistance connections to the ground goes a long way too.
"onward!" cried the copper man, little knowing brass corrupts...
Hey! But current depends on voltage! (and V on I - and R of course). Large voltages and low impedance will produce high currents. The TIME for engaging the protective devices is crucial. I bet that MOVs are faster than fuses or breakers.
"... you are only really worried about a lighting strike on the power grid in close vicinity and on your circuit. "
..."
True. A direct strike would burn everything in its path, including surge protectors.
"So dependent upon your circuit board,
Not correct. It is VERY useful to have surge protection that can handle a huge amount of energy, that is, a high number of joules. The protection needs to be on the power line, not inside equipment. If possible, you want the surge protector to burn, not your equipment.
www.lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
"onward!" cried the copper man, little knowing brass corrupts...
"Ground rods' high impedance as opposed to a proper grounding conductor..."
Well, actually it's how conductive the contact between the ground rod and the ground is, which is influenced by what is used to make the ground rod (many nowadays are steel, to facilitate driving them into the ground, covered with copper, to facilitate conduction), and whether the proper material is used in the ground rod clamp.
I'm curious what you mean in the above by a proper grounding conductor.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
I can't agree. My aunt's house was hit by lightning and charge went to ground via her water pipes. The biggest pipe, however, was a central line running from one side of the house (laundry, kitchen) to the other (bathrooms). The pipe was embedded in the concrete slab foundation.
The heat was so intense the carpet was discolored, the pad below that melted, and the concrete lost all integrity. It turned into a brittle mess that would break under the weight of a solid heel. You could take a framing hammer and break it apart with results similar to what you'd expect if you were using a jackhammer.
She had to have a giant trough of concrete removed from her foundation along the path of the pipes, then new pipes, new concrete, new padding and carpet.
Frankly, I wasn't surprised. Trees on my property have been hit twice and one two doors down was struck just a couple of weeks ago. In every case, the damage to my house was obvious, although only one was serious (as in - killed everything electronic in the house.) Thank goodness for insurance.
If you have an open slot in the breaker panel for another two-pole unit, you may be able to get a surge protector that installs right in the breaker panel. This avoids having anything attached in the open, or having to "tear open the wall" to replace it. Look for a "Type 1" or "Type 2" surge protector, made for your make and model of breaker panel In most places, you have to hire a licensed electrician and get a permit to legally install it. You will also need protection for TV/satellite cables, etc. These need to be physically close to the power line protector, and be connected to the same ground system, through a short fat wire. Using a separate ground stake and a long, skinny grounding wire (as too many inept installers do) can actually increase the risk of damage: surge currents flow from the AC line, through your flat screen TV, and out the coax cable to the cable's ground rod. Goodbye flat screen TV, hello fire department!
Your insurance company may insist on it being installed by a licensed electician even if local codes don't.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
Which also lets you take off your tinfoil hat indoors.
"Is life so dear, or peace so sweet, as to be purchased at the price of chains and slavery?" - Patrick Henry
OP here. Forgot to mention, if your house has an isolated neutral bar (most don't, but if it's very new it may), you'll want to buy two, and tie one to neutral and the other to ground. This will give you L-N and L-G protection, and they'll both do L-L.
The presence of an isolated neutral is dictated by panelboard (circuit breaker box) location.
At the service entrance (meter box) the (white wire) neutral, also known as the grounded conductor, is bonded to ground, as is the (bare or green wire) grounding conductor. The "neutral" is really only neutral in a 240V circuit, in a 120V circuit it carries the same current as flows through the "hot" wire.
The "ground" wire is only supposed to carry current if something goes wrong.
In any breaker or junction box "downstream" from the meter/service entrance, the "ground" wire goes to a buss bar that's bonded to the cabinet, and the "neutral" goes to a buss bar that's isolated and electrically insulated from the cabinet. The "neutral" is not connected to "ground" or anything which is grounded except at the service entrance.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
"Get 2 ea. 6' copper ground spikes ... Careful not to bend them too much in the process. They aren't iron."
Yes, they are. They're just copper-plated.
"Is life so dear, or peace so sweet, as to be purchased at the price of chains and slavery?" - Patrick Henry
http://www.mikeholt.com/technical.php?id=grounding/unformatted/Groundrodfault&type=u&title=Ground%20Rod%20Does%20Not%20Assist%20in%20Clearing%20a%20Fault%20(01-25-2K) http://forums.mikeholt.com/showthread.php?t=107483&page=2 and http://forums.mikeholt.com/showthread.php?t=139984&page=6
explain why a ground rod does not assist in clearing a fault. The problem is not the copper ground rod but the earth itself. A proper grounding conductor is the bare copper wire that's part of the branch circuit wire that eventually goes back to the equipment grounding bar in a sub- or service (main) panel.
Yeah, after living in a couple places that had bad grounds and only two-prong outlets, I made sure to buy a house that had at least three-prong outlets.
Then after I bought the house, I found out someone had replaced the grounding rod with a PVC pipe... /facepalm
Just use surge protectors where needed that have an equipment replacement guarantee
Those guarantees are usually worthless I'm afraid. If you read the small print they require you to send affected items to them for evaluation. Do you really want to send them your fridge and wait for them to decide if a surge killed it and then buy you another (inferior) one?
Just get home contents insurance with a reasonable policy.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
I don't have an engineering degree, but I do have a degree in computer science, which I obtained 20 years before I did my MBA. My job is actually as a computer scientist.
The order in which you place the options is (at best) a matter of personal preference; I'd in fact consider it darned near close to meaningless. I don't know about the best practices in engineering, but in science - and in business, actually - you're supposed to treat all options equally and assess them on their relative merits.
However the pure cost-driven analyses often miss important factors.
Agreed. I've never seen a scenario where things are done purely on the basis of cost. That's why I closed my post with the phrase "Expenses, risks, benefits".
I know it's fashionable to pan MBAs and other business exec types, especially with the Wall Street failures over the last few years, but I've yet to meet an executive who doesn't consider risks and other non-cost-based factors. The mortgage crisis wasn't due solely to people being greedy; it was due to people being greedy and using the wrong risk models. They got the figures wrong, but they did consider the risks.
Current divides based on the ratio of admittance, not resistance. Which, yes, is the inverse of ohms.
The best bet is to have a good, heavy gauge copper ground at your breaker box / meter. The admittance ratio to ground will be the highest there.
I am in now way downplaying your info, but I just want to give my few experiences with lightning.
One summer we had a ton of lighting storms and we had replaced well over 15 modems for people who got "hit", but non of the computers actually got hurt, just dead modems.
I was at my friend's house when lightning hit near-by as the flash and thunder happened at the same time. It sounded like the air was ripping apart. The lights flashed quite brightly. My computer and 5port 10/100 switch was plugged into my UPS. My computer was fine. My friend's computer was no on any surge protection and his NIC got killed. The rest of his computer was fine, but the voltage spike entered his computer and not only took out his NIC, but also the port on my switch the NIC was plugged into.
My switch slowly died over the next month, but originally it was only the port he was plugged into.
Surge protectors are good, but not 100%. Like other have mentioned, a direct strike can do anything.
I would still invest into whole house protection because I would rather put money into something that could very likely help me compared to some other random crap.
and inexpensive protection for sensitive expensive devices. A close-by lightning hit can toast most anything, so forget about it. If you want to install a motor-generator for the whole house, get a second mortgage and plan to pay for the extra energy it will waste. Lightning may damage the motor side but might not hurt anything connected to the generator.
Most of the damage my stuff has received during storms has been through low voltage connections (phone lines, network cabling, coax) caused by inductive spikes. Use protection on these connections and/or eliminate them (WiFi, TOSLink, etc).
Having grounds at a different potential can wreck havoc on signal circuits too. In the '70s I ran the newsroom of a Canadian radio station and we were getting hum on the phone lines, enough to make it annoying when we did interviews over the phone and then used the clips on the air. I spoke to our chief engineer and we went up to the phone distribution frame above the studio complex. I asked for his multimeter to check the ground on the power outlet against the ground on the phone company rack. Sure enough there was a 5 volt difference.
I said, "I bet if we tie those two grounds together with four gauge wire, the hum will disappear." The chief engineer looked at me funny, not realizing I had been tinkering with electronics most of my life, plus I studied electrical engineering and I had an FCC first phone ticket, but I liked news better, especially on rock and roll radio.
Of course he was also baffled when I asked for the cart machine cue lights to be displayed in the news booth. He said "There are six machines in the control room and I only have three pair going to the news booth." I drew him a quick diode array and said, "Here. You can do it on a pair and a half." He left scratching his head but built it and it worked.
There was a downside though when he came into my office in the newsroom two weeks later with a roll of blueprinted schematics and asked for help with the 50KW AM transmitter modulator circuit.
If your only tool is a hammer, you'll approach every problem as if it were a nail. - Abraham Maslow
I live in Sunny Florida, Unfortunately Tampa... The "Lightning Capital" of the USA. Our local Power company offers a product called a "Zap Cap". This device attaches between (behind actually) the meter before the power heads into your Main. The Device is cheap because there is a trade off, You agree to volenteer to have your home effected by things like rolling blackouts and such (tho I am unaware of one happening to my home in the past 15 years). Since we had it installed I have not suffered as I have from not just computer loss but with anything with a chip (washer /dryer , dish washer Microwave etc). Ive had very near strikes but
none direct hits. (as explained above your would need a huge something to dampen them(). Anyway check that source.
I should add that if you have iron pipes, you can get much of the same protection by grounding to the water pipes at the closest point to where they run underground.
That might not meet code, these days, but it used to for a very long time. And it will give you a serviceable ground.
Don't ground to your gas pipe, though. Not A Good Idea.
In my locale, it is absolutely against the law to ground to a water pipe that is more than a three feet from where it enters the ground. If lightning strikes the power pole near the house, the high amperage from the surge can cause the water in the pipe to heat to steam and even burst the pipe. Damage may not be insurable because of a wrong ground. On the other hand, I have a ground at a waterpipe in the laundryroom because the house wiring was old. But the ground was made with number 18 wire. The wire would melt and act like a fuse if the house was hit with lightning. I also have a GFI outlet. (House has 120-240 wiring)
Leslie Satenstein Montreal Quebec Canada
You can have more than one ground, but they must be bonded together at the service panel so no potential develops between them.
In fact, one state where I lived a few years ago required at least 2 six-foot ground spikes to meet code, and required the pipes to be grounded as well if the building was plumbed.
That's a bit off-topic, though. We were discussing whether a serviceable electrical ground can be made using the water pipes. For many years, that all by itself met the requirements of construction code. Not for a long time now, in most places... but it does work.
As for lightning strikes: remember that OP was talking about a house that had no ground at all. Just about any ground is still going to be better than none.
Lightning can do some strange things, though. Some years ago, 2 workers were putting up a metal shed in my sister's back yard, which has a concrete retaining wall. A storm started up. Lightning hit a tree near the wall, went down to the ground, then shot out the side of the retaining wall, across about a 12-foot air gap, and zapped the 2 workers, who had to be run to the hospital. One was seriously injured.
Not much will protect against a direct strike except maybe a high rod to attract it to ground. When I was in 6th grade running just behind my friend to get to his house in a bad storm a lighting bolt struck right between us leaving a mark. Talk about a weird, close call!
No I can't, I was already born years ago. Hows THAT for protection.
"I opened my eyes, and everything went dark again"
It seems certain he is not "required".
If another store decides to prevent misleading product descriptions, and Home Depot doesn't, Home Depot will go bankrupt. It's that simple, in my opinion.
Current divides based on the ratio of admittance, not resistance. Which, yes, is the inverse of ohms.
Electrical current isn't the only thing that matters. A static charge can still do a great deal of damage.
The characteristics of lightning discharge are variable, no matter how thick you make that copper, there is a possible lightning strike intensity that will defeat it, and you can't affordably make that copper thick enough.
Especially if the direct strike is inducing voltage in your inside wiring a significant distance away from your main panel.
In the old days I protected it via 12 volt battery. Charger charged the 12v battery, on the other side I made a power supply that had to provide 12, +5 leads. Worked very well. I think that computer consumed a whole 20 watts, if that. Not even a fan cooled CPU.
In the 1990s I got a Best UPS with the Ferro transformer. I still use them and they work very well though they are a bitch to get today. Even then, a bolt hit about 15' away, a tree. It knocked out my parrallel card to the printer. $15 later and I was back in action.
Another noteable hit was about 6 years ago. My house was in a really bad spot. Bolt after bolt after bolt was hitting outside, very close. Heavy rain. It fried my cable modem, switch, some other interfaces. It was because the cable coming in wasn't connected to the ground. So the ground was through my machine. I think all it took was about $200 at Best Buy and I was back in action.
I've never had a case where it took out my machine entirely. Just the interface cards.
Conventional wisdom now seems to be to get yourself a 8' copper rod. You'll want to sink that into the ground, about 6" below the surface and pull a lead from that to ground your house and anything coming in. Be sure to call miss-utility before digging or sinking a rod if you do it. Better yet, get an electrical contractor to do it. Yes, he'll probably say it's un-necessary. Depends on where you are. In some counties they now require 3 - 8' rods hooked together. Lots of crazy stuff I found as I had to replace a perfectly good breaker box because the City didn't think a 40 year old box was any good anymore. So if you do anything to do with electric, you must replace it. I had to replace the weather head. Some places like Las Vegas have some of the strictest rules. I had to put cat-5 in conduit. No lose plenum for them!
It does not make much sense to say that voltage "passes through" a resistor; it would be current.
It makes sense to say that a high voltage in the form of a static charge passes through a resistor, and discharges through a piece of electronics, destroying sensitive components such as semiconductor-based logic gates. When a resistor is subjected to a voltage on one side, a voltage difference builds at the input terminal of a resistor until the resistance is overcome by the difference in the potential at the output terminal, and then this difference must be equalized. There is a "drop" in voltage between the two terminals of a resistor, but this drop is not infinite, given a sufficient voltage on one side of the resistor -- the voltage will be discharged to the other side of that resistor, there might be current in the form of a circuit, there might not be.
As far as lightning is concerned, a thick piece of plastic can be a resistor, as can be plain air, and other materials that are normally conductors -- the voltage is certainly high enough, considering the lightning strike travelled miles through the air to hit something near the soil... what's a few more feet?
If you're electrically incompetent enough to get that sort of thing wrong, then you need a few doses of ECT to try to get the brain cells moving again.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Thanks, I got confused.
So, there you have it: The economy isn't that bad. People are just lazy fucks.