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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?"
http://www.dehn.de/pdf/blitzplaner/BBP_2007_E_complete.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.
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.
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"
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.
Unless your dealing with medical equipment or servers don't bother with some expensive custom solution.
This isn't an expensive custom solution. It's becoming more common in new construction. Home Depot has several models to choose from, some as low as $30.
The question is, how good is it?
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
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.
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 bought a kit that included the part that an electrician installed connected to the breaker box, an inline piece for cable, and another for telephone. It was recommended to put expensive electronics on smaller plug-in surge protectors to guard against the very brief leakage that can occur just before the whole-house protector blows. This after a buddy just uphill from me lost the electronics in just about everything (dishwasher, garage door opener, etc.) but not his computers.
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.
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.
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.
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).
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.