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  #1  
Old 08-20-2009, 11:07 AM
redtail23 redtail23 is offline
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Surge Suppressors

How many joules protection is needed for home electronics (computers / home theatre / etc.)?

When I look at suppressors, the primary difference seems to be how many joules they're rated for. (I mean, aside from the obvious differences in number of outlets, etc.) The more joules, the more $$$. I don't mind paying the bucks if it's doing some good, but I don't want to spend extra for no real benefit.

I live in the middle of Oklahoma, so lots of storms, lots of lightning. The power at this house seems more stable than some I've had, but still flickers occasionally plus occasional outages during storms.

For instance, I was looking at something like this the other day. Is "unlimited joules" worth the extra $10-$15 over comparable models with (1500/2500/3500/etc) joules?

I've also been looking at whole-house systems. Here's an example. Would something like that eliminate the need for individual suppressors on all the equipment, or do you still have to have strips for everything? Has anyone tried one of these?

Thanks.
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  #2  
Old 08-20-2009, 12:09 PM
engineer_comp_geek engineer_comp_geek is online now
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The more joules the better. Nothing is going to protect you from a very close lightning strike. Lightning contains many billions of joules of energy, and I have yet to see a 50 billion joule surge suppressor on the market. It is much more common to get damage from lightning that has traveled some distance down a power line, and that's the sort of thing that these types of surge protectors will protect you from.

A whole house protector is good, but if you get a really big strike it won't protect everything. A little additional protection from individual power strips helps a bit in that case.

Note that these types of things only protect you from overvoltages. They don't protect you from undervoltages (brownouts) or flickering power. Quite often your electricity will "flicker" because there's a temporary fault on the line, like the storm has blown one line into another or has blown a tree branch onto the lines. This causes a protective device to trip, just like the breakers in your house when you try to draw too much power from an outlet. Unlike your home breakers, power lines have these things called automatic reclosers. These function like having an automatic guy standing next to your breaker box. When someone trips a breaker, he automatically flips it back on. If it keeps tripping, he says ok, it's really a fault and leaves it off. This allows the power company to automatically fix transient faults like wind-blown power lines and tree branches, so that you lose power for only a second or two instead of the few hours it would take for a lineman to get out there and reset the breaker.

If you want to protect yourself from brownouts and flickering, you need a UPS.
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  #3  
Old 08-20-2009, 12:36 PM
HorseloverFat HorseloverFat is offline
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Wouldnt a lightning strike blow the fuse before it had a chance to damage the computer or would it just jump the fuse?
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Old 08-20-2009, 12:40 PM
Harmonious Discord Harmonious Discord is offline
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A fuse does nothing for lightning.
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  #5  
Old 08-20-2009, 01:14 PM
redtail23 redtail23 is offline
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Quote:
Originally Posted by engineer_comp_geek View Post
Lightning contains many billions of joules of energy, and I have yet to see a 50 billion joule surge suppressor on the market.
*snicker* Well, that's what I thought. But these are "infinite joules" suppressors, mind you.

Quote:
A whole house protector is good, but if you get a really big strike it won't protect everything. A little additional protection from individual power strips helps a bit in that case.
So if you still have to have the individual strips, what's the point of the whole-house protector? I was all excited that my electric company offered these, until I read the fine print that said I still had to have strips for everything.

Quote:
If you want to protect yourself from brownouts and flickering, you need a UPS.
Yup, I've got UPS on some stuff, but I've been told there's no point to a UPS for the TV. I do need a new surge suppressor for it, though.

Do you really have to replace them yearly? The Phillips one I was looking doesn't have a warranty period, it just says that it may quit surge-protecting without warning and still seem to be working, so you'd be SOL then. Annoying.

What I really want is a solar roof and windmill with a giant battery system and a natural gas backup generator. When I win the lottery...
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  #6  
Old 08-20-2009, 02:18 PM
johnpost johnpost is offline
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if you can hear thunder you can get hit directly by lightning according to NOAA.

surges caused by lightning can travel through the power and phone grid in rural areas for many miles, there are less places for it to go to ground.

some electronics like to have power to hold memory (setups) and a UPS is good for those.

if you care about your electronics, especially if you are rural, then you could unplug your electronics and phone and antennas when you have a thunder storm. keep a battery powered tv or a low cost one available for storms, same with radio (weather band radios are great) and use a low cost cordless phone during storms.

less expensive surge protectors use a MOV, that will last once to a number of times depending on what happens to it. after that device has been used up the surge protector is just a power strip.
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Old 08-21-2009, 12:08 PM
westom westom is offline
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Quote:
Originally Posted by redtail23 View Post
When I look at suppressors, the primary difference seems to be how many joules they're rated for. (I mean, aside from the obvious differences in number of outlets, etc.) The more joules, the more $$$.
So you think those few hundred joules in a protector will absorb surges that are hundreds of thousands of joules? Do you think that silly little 2 cm part inside that power strip will stop what three miles of sky could not. So how does you telco connected to overhead wires all over town, not lose their switching computers? Clearly they disconnect when thunderstorms approach so that the next four days have phone service.

Oh. Their phone system works just fine after 100 surges from every thunderstorm? How can this be. We were told nothing protects from direct lightning.

Lets talk reality - what a protector does. From the NIST (US government research agency):
> You cannot really suppress a surge altogether, nor "arrest" it.
> What these protective devices do is neither suppress nor
> arrest a surge, but simply divert it to ground, where it can do
> no harm.

So which protectors made that low impedance ('less than 10 feet', no sharp wire bends, separated from other wires, no splices, etc) connection to single point earth ground? A major difference. Many of the protector you were viewing do not even claim surge protection in their numeric specs. Do not even claim protection - let alone avert damage from a direct strike.

Same reason why telcos never use those ineffective and obscenely overpriced protectors from APC, Tripplite, Monster Cable, Belkin, etc. They need protectors that work - not a scam.

As the NIST says, protectors work by diverting energy to ground, where it can do no harm. Either energy is harmlessly absorbed without entering the building (ie 'whole house' protector). Or energy goes hunting for earth destructively via household appliances. Your choice. IOW surge damage is directly attributed to human failure - even from direct strikes.

Only more responsible companies sell 'whole house' protectors. Add to that long list General Electric, Intermatic, Keison, Polyphaser, Leviton, Square D, and Siemens. The Cutler-Hammer protector sells in Lowes for less than $50. That is effective protection for about $1 per protected appliance. Or tens or 100 times more money for scam plug-in protectors - that do not even claim protection in their numeric specs (did you read those specs yet? Why not? The fact is that damning.)

Every responsible source says, essentially, the protector is only as effective as its earth ground. For example, IEEE Red Book (Standard 141):
> In actual practice, lightning protection is achieve by the process of interception
> of lightning produced surges, diverting them to ground, and by altering their
> associated wave shapes.

Why so many protectors and none discuss earthing? For the same reason why so many believed Saddam had WMDs. When facts and numbers arrive, most eyes just glaze over. A protector is only as effective as its earth ground. Plug-in protectors have no earthing AND do not even claim to provide that protection.

Critical is to upgrade your earthing - what actually does the protection. It must meet and exceed post 1990 National Electrical Code. If the ground wire from breaker box to earth ground is too long (ie 'more than 10 feet''), many sharp bends, splices, inside metallic conduit, bundled with other non-grounding wires, etc - then earthing has been compromised. If the wire goes up over the foundation and down to earth, then too long, too many sharp bends, bundled with other wires. It must go through the foundation and down to earth.

See what is important? What does lightning seek? Earth ground. A protector is only as effective as its earth ground.

Did you know all phone lines already have a 'whole house' protector installed - for free? Installed because it is so effective and so inexpensive - especially compared to those hyped plug-in protectors. But again, what makes that protector effective? Well, how good is the earth ground that you are responsible for providing?

Cable TV needs no protector. It must connect that 'less than ten feet' to the same earth ground via a ground box and wire.

Described is technology well proven in science, patents, and experience for over 100 years. Notice how few know any of this for the same reason why so many knew Saddam had WMDs. Many will only repeat what they were told to think. Never asked simple question. 2nd grade science. How did Franklin stop and block lightning from church steeples? He didn't. Franklin simple used the same principles that are found only with effective protectors. Either the surge finds earth ground destructively via church steeples and appliances. Or that energy gets harmlessly diverted and absorbed in earth (lightning rods and 'whole house' protectors). And still some will claim a plug-in protector stops or absorbs surges. Myths are widespread. Facts become obvious when learning from some simple concept such as 2nd grade science and Franklin's solution.

A protector is only as effective as its earth ground. How to identify scam protectors: 1) No dedicated wire to earth ground. 2) Manufacturer avoids all discussion about earthing. 3) The so called complete solution (a magic box) does not even claim to provide protection in its numeric specs. That should eliminate most of what you were reviewing.

Where does all that energy dissipate? A protector is only as effective as its earth ground.
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  #8  
Old 08-21-2009, 02:26 PM
jakesteele jakesteele is offline
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Main site:
http://www.transtector.com/

Specific site:
http://www.transtector.com/productdetail?item=1100-545


I used to sell business telephone systems way back when in the early to mid '90s and we always built one of this companie's products into the install. At the time they were far and away the best in the market. They operated on something called, "silicone diaode avalanche technology", which as a salesman I never really understood. The techs said it was wiz-bang and after I saw it in action I realized that they were right. I still have the ones I bought from my company on my computers today.
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  #9  
Old 08-21-2009, 03:06 PM
westom westom is offline
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Quote:
Originally Posted by jakesteele View Post
I used to sell business telephone systems way back when in the early to mid '90s and we always built one of this companie's products into the install.
Did they mention every subscriber line - where their wires meet yours - already has a ‘whole house’ protector? A protector was required even in the 1950s? Telcos have been using the effective protection for over 100 years. Did they forget to mention that? Or did they just promote a protector because it will make surge energy magically disappear?

Effective protectors - even silicon avalanche diodes - are about connecting surge energy harmlessly into earth. If that ‘low impedance’ connection does not exist, an avalanche diode can even earth that energy destructively through nearby appliances.

So that their computer never has damage, telcos install avalanche diodes (or so many other and similar technologies) within feet of earth ground and up to 50 meters separated from electronics. Why? Were does that energy get harmlessly dissipated? Surge protection without answering the question is ineffective.

What does the US Air Force do to never have surge damage? From the Air Force training manual:
> 15. Surge Protection.
> 15.1. Entering or exiting metallic power, intrusion detection, communication antenna,
> and instrumentation lines must have surge protection sized for lightning surges to
> reduce transient voltages to a harmless level. Install the surge protection as soon as
> practical where the conductor enters the interior of the facility. Devices commonly
> used for this include metal oxide varistors, gas tube arresters, and transzorbs.

A protector does not provide protection. A protector connects surges TO protection. A protector is only as effective as its earth ground - not matter how many recited only what they were told to think, or try to spin otherwise.

Damning questions – where does that energy get absorbed?
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