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Lightning Protection?

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burgarwulf

New Around Here
So we had a pretty major lightning storm Monday night, right outside the house (those see the bolt immediately hear high decibel crackling) and before I could think about it the lights were flicking.

This happened about the same time last year, and it wiped out an ASUS RT-N66U and little 4 port Linksys switch and the RJ-45 on a surge protector.

Well this time it finished off both our Cable and DSL modems (dead, no activity), its definitely damaged the WAN and two ethernet ports on the ASUS, think it took out all ports on the ancient Dell True Mobile 2300.

They were all in surge protectors, but it appears no one ever replaced the protector with the fried out RJ-45, so the DSL modem was direct into wall. After some reading it seems most suggest not pushing DSL or Cable through their respective protectors due to loss of signal quality/interference?

Not really the scope of this forum but I suspect there is a ground loop, something isn't properly wired, and I suspect its the telephone line (cable was a fresh run installed last year, directly grounded to the breaker box).

But my real question is...is there any true protection from this? $300 on ASUS routers and hassling my ISPs this much is tiring. I suspect any sight of a lightning storm will have my scrambling to unplug the modems.
 
lol here comes the dog fight over lightning and surge protection

all i will say is if you live in an area that is prone to strikes get a better insurance policy and perhaps run stuff like that behind an UPS
 
"A lightning rod (US, AUS) or lightning conductor (UK) is a metal rod or metallic object mounted on top of an elevated structure, such as a building, a ship, or even a tree, electrically bonded using a wire or electrical conductor to interface with ground or "earth" through an electrode, engineered to protect the ..."

https://en.wikipedia.org/wiki/Lightning_rod
 
Seems excessive for the max two weeks in Spring we get it though?

From the loose reading I've done over the past few days, a surge protector isn't going to do much to stop a lightning based surge? Its not like the house was hit directly (I've seen no evidence) but the lines coming into the house must've gotten charged somewhere in the nearby system.

Sounds like just unplugging the modems is going to be the end-all best bet? I was just curious.
 
From the loose reading I've done over the past few days, a surge protector isn't going to do much to stop a lightning based surge? Its not like the house was hit directly (I've seen no evidence) but the lines coming into the house must've gotten charged somewhere in the nearby system.

Sometimes you'll be ok with a direct hit, sometimes you'll be taken out by a hit 5 miles away - depends on the path taken.

A quality surge suppressor is a good idea - just note that they are expendable items and need to be replaced periodically depending on the environment...
 
This raises an interesting question though about HomePlugs and to a lesser extent MOCA..

Since surge suppressors will typically impact their performance, what is the onboard protection for those devices - not just GFI, but a bit more...

@thiggins - have the vendors shared anything there?
 
"A lightning rod (US, AUS) or lightning conductor (UK) is a metal rod or metallic object mounted on top of an elevated structure, such as a building, a ship, or even a tree, electrically bonded using a wire or electrical conductor to interface with ground or "earth" through an electrode, engineered to protect the ..."

https://en.wikipedia.org/wiki/Lightning_rod

Lighting rod did not protect when system running Multics OS located in the basement of 7 story
building got direct hit. System was on M-G power. floor full of mass storage data was scrambled beyond
recovery other than total system restore. From personal experience.
 
Nothing's perfect eh?

Our DC's - at least the two in the "mid-west" - DEN/ORD, belt and suspenders as both of these locations are lightning country - and good friends over in KC - which is even worse...

Lightning Rods, Strong Grounding, conditioned power on all the racks, and a huge UPS on the back end... layered approached.

Even then - things get scrambled once in a while - million volts and a fair amount of current will do that..
 
Lighting rod did not protect when system running Multics OS located in the basement of 7 story
building got direct hit.

From one graybeard to another - nice to meet you... never saw multics, but I did have access to UCSD pascal via UND's TimeShare system back in high school... and that was quite a few years after Unix went "production" and the Berkley work)

For others - Multics preceded Research Unix by a few years... but Unix was born out of frustration with Multics and corp politics - and the rest is of course, history...
 
lol here comes the dog fight over lightning and surge protection

all i will say is if you live in an area that is prone to strikes get a better insurance policy and perhaps run stuff like that behind an UPS

+1 BIG UPS costs $$$. Just protect most important stuff on UPS. In my neighborhood all cables are under ground. So far never lost anything from lightning strike.
From one graybeard to another - nice to meet you... never saw multics, but I did have access to UCSD pascal via UND's TimeShare system back in high school... and that was quite a few years after Unix went "production" and the Berkley work)

For others - Multics preceded Research Unix by a few years... but Unix was born out of frustration with Multics and corp politics - and the rest is of course, history...

I was EIC at UofC system from '70s to late -90s. Had worked with people at CISL at MIT and hardware design engineers. Multics OS was in PL1 ~50K line codes if I remember correct. U0fC computer science dept. was involved in hw/sw development project on Multics. At peak time there were about 100 Multics system world wide. On the same floor there were CDC EMT, Gray main frames and IBM system too. I am on the wrong side of 70, don't feel like old, LOL! Marketing people killed Multics for GCOS and CP6 which killed Honeywell's IS business. There is still Multics
forum on the net where old timers hang out.
 
I am on the wrong side of 70, don't feel like old, LOL

I'm on the wrong side of 50 - and having worked DoD systems long time back, the old stuff has momentum that carries long beyond the start of the art - I still recall having to learn UYQ-20 byte code for ultra16... and the less talked about ada, the better, lol...

Good to meet you, sir...
 
From the loose reading I've done over the past few days, a surge protector isn't going to do much to stop a lightning based surge? Its not like the house was hit directly (I've seen no evidence) but the lines coming into the house must've gotten charged somewhere in the nearby system.

First, you have assumed lightning can be stopped. Direct lightning strikes without damage are routine. But only if you do what Ben Franklin demonstrated in 1752.

Lightning rods do not protect structures by 'stopping'. Nothing does that. A lightning rod is only as effective as its earth ground.

Protectors doe not protect appliances by 'stopping'. A protector is only as effective as its earth ground.

Nobody has discussed what does protection - what harmlessly absorbs hundreds of thousands of joules. If any wire inside any incoming cable does not connect to earth, then lightning was all but invited inside to hunt for earth destructively via electronics. Destructive surges are typically once every seven years. Robust protection inside all appliances makes most surges irrelevant. But you had a surge so massive as to blow through existing protection. Adjacent (plug-in) protectors may have even made that damage easier.

Second, what may have happened? A direct lightning strike far down the street was incoming to all appliances. Are all destroyed? Of course not. Lightning is electricity. Both an incoming and an outgoing path to earth must exist.

Lightning found an outgoing destructive path to earth via an RJ-45 cable that connects to a breaker box and then to earth ground. Internet appliances were a better outgoing path. Therefore a dishwasher, clocks, furnace, TV, smoke detectors, and other appliances were undamaged.

Once a surge is inside, nothing does and nothing claims to protect appliances. Protection is always about how that transient connects to earth. A low impedance (ie less than 10 foot) connection from cable direct to earth ground. Same must exist for an 'installed for free' protector on any incoming phone lines. A protector is only doing what a direct hardwire does better. All incoming wires must make this same low impedance (ie hardwire has no sharp bends) connection to earth.

Third, obviously cable needs no protector if a hardwire connected low impedance (ie not inside metallic conduit) to the earthing electrode (not breaker box). Then hundreds of thousands of joules are not inside hunting for earth destructively via appliances.

If a breaker box 'whole house' protector is connected via a hardwire that goes up over the foundation and down to an electrode, then protection is compromised. Hardwire is too long. Sharp bends exist when going over the foundation. Hardwire is not separated from other non-grounding wires. Plug-in protectors (obviously without earth ground) only did what they claim to do. And may have made damage easier.

Averting future damage starts with inspecting what actually does protection - single point earth ground. Not just any earth ground. World's best protector is useless if not connected low impedance (ie less than 10 feet) to this unique and essential ground. Either by hardwire or via a protector.

Inspect earth ground for both 'secondary' protection layer at your service entrance and a 'primary' protection layer typically on a utility pole. Only earth ground (not any protector) defines each protection layer.

How many never learned this and did not discuss here what has done appliance protection from direct lightning strikes for over 100 years? How many foolishly assumed an adjacent protector or UPS does effective protection? Same protection is needed even if incoming utility wires are underground. A protector is only as effective as its earth ground.
 
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You can protect networking ports from lightning but they shouldnt be with the same surge protector box as your plugs are because lightning when you have breakers, fuses, exploding capacitors the lightning remains as static electricity so they can jump to other things. Many devices like networking components do not have earth as they only use 2 pins. If you see the PSU of a computer or even something that uses 3 pins you will see that earth is connected to a metal case to allow electricity to jump to case than to earth.

You will find that your networking gear gets fried but all other gear are still fine, its because they have an earth for the lightning to jump.

The benjamin frankling rod is more to prevent lightning from striking things directly. If your computer was hit by lightning directly it would destroy all the components that even the planned circuit protection wont work as it wont follow the circuit path. Most lightning strikes come through the electricity lines.

So some of the post above is irrelevant in this case because its not the quality of earthing, none of the networking gear have earthing. They also use switching PSUs that have a very low tolerance spec in that a big surge destroys them. Even if a plug is 3 pin many of them just have an insulator as an earth pin as they have no earth, its just for ease of use.

If wiring is a hassle perhaps wifi might be to your liking, you could always get those wireless charging pads and use wifi for everything even for connecting to the modem.
 
My semi manged switch uses a 3 pin power cord that is interchangeable with cords for my PCs and monitors

But all the same, it would seem reasonable that if all equipment that has a wire like ethernet or coax is hooked up to a decent Surge suppressor all is good.

Of course this is also just one reason of many for regular backups
 
I'm on the wrong side of 50 - and having worked DoD systems long time back, the old stuff has momentum that carries long beyond the start of the art - I still recall having to learn UYQ-20 byte code for ultra16... and the less talked about ada, the better, lol...

Good to meet you, sir...
,
First, you have assumed lightning can be stopped. Direct lightning strikes without damage are routine. But only if you do what Ben Franklin demonstrated in 1752.

Lightning rods do not protect structures by 'stopping'. Nothing does that. A lightning rod is only as effective as its earth ground.

Protectors doe not protect appliances by 'stopping'. A protector is only as effective as its earth ground.

Nobody has discussed what does protection - what harmlessly absorbs hundreds of thousands of joules. If any wire inside any incoming cable does not connect to earth, then lightning was all but invited inside to hunt for earth destructively via electronics. Destructive surges are typically once every seven years. Robust protection inside all appliances makes most surges irrelevant. But you had a surge so massive as to blow through existing protection. Adjacent (plug-in) protectors may have even made that damage easier.

Second, what may have happened? A direct lightning strike far down the street was incoming to all appliances. Are all destroyed? Of course not. Lightning is electricity. Both an incoming and an outgoing path to earth must exist.

Lightning found an outgoing destructive path to earth via an RJ-45 cable that connects to a breaker box and then to earth ground. Internet appliances were a better outgoing path. Therefore a dishwasher, clocks, furnace, TV, smoke detectors, and other appliances were undamaged.

Once a surge is inside, nothing does and nothing claims to protect appliances. Protection is always about how that transient connects to earth. A low impedance (ie less than 10 foot) connection from cable direct to earth ground. Same must exist for an 'installed for free' protector on any incoming phone lines. A protector is only doing what a direct hardwire does better. All incoming wires must make this same low impedance (ie hardwire has no sharp bends) connection to earth.

Third, obviously cable needs no protector if a hardwire connected low impedance (ie not inside metallic conduit) to the earthing electrode (not breaker box). Then hundreds of thousands of joules are not inside hunting for earth destructively via appliances.

If a breaker box 'whole house' protector is connected via a hardwire that goes up over the foundation and down to an electrode, then protection is compromised. Hardwire is too long. Sharp bends exist when going over the foundation. Hardwire is not separated from other non-grounding wires. Plug-in protectors (obviously without earth ground) only did what they claim to do. And may have made damage easier.

Averting future damage starts with inspecting what actually does protection - single point earth ground. Not just any earth ground. World's best protector is useless if not connected low impedance (ie less than 10 feet) to this unique and essential ground. Either by hardwire or via a protector.

Inspect earth ground for both 'secondary' protection layer at your service entrance and a 'primary' protection layer typically on a utility pole. Only earth ground (not any protector) defines each protection layer.

How many never learned this and did not discuss here what has done appliance protection from direct lightning strikes for over 100 years? How many foolishly assumed an adjacent protector or UPS does effective protection? Same protection is needed even if incoming utility wires are underground. A protector is only as effective as its earth ground.
 
First, you have assumed lightning can be stopped. Direct lightning strikes without damage are routine. But only if you do what Ben Franklin demonstrated in 1752.

Lightning rods do not protect structures by 'stopping'. Nothing does that. A lightning rod is only as effective as its earth ground.

Protectors doe not protect appliances by 'stopping'. A protector is only as effective as its earth ground.

Nobody has discussed what does protection - what harmlessly absorbs hundreds of thousands of joules. If any wire inside any incoming cable does not connect to earth, then lightning was all but invited inside to hunt for earth destructively via electronics. Destructive surges are typically once every seven years. Robust protection inside all appliances makes most surges irrelevant. But you had a surge so massive as to blow through existing protection. Adjacent (plug-in) protectors may have even made that damage easier.

Second, what may have happened? A direct lightning strike far down the street was incoming to all appliances. Are all destroyed? Of course not. Lightning is electricity. Both an incoming and an outgoing path to earth must exist.

Lightning found an outgoing destructive path to earth via an RJ-45 cable that connects to a breaker box and then to earth ground. Internet appliances were a better outgoing path. Therefore a dishwasher, clocks, furnace, TV, smoke detectors, and other appliances were undamaged.

Once a surge is inside, nothing does and nothing claims to protect appliances. Protection is always about how that transient connects to earth. A low impedance (ie less than 10 foot) connection from cable direct to earth ground. Same must exist for an 'installed for free' protector on any incoming phone lines. A protector is only doing what a direct hardwire does better. All incoming wires must make this same low impedance (ie hardwire has no sharp bends) connection to earth.

Third, obviously cable needs no protector if a hardwire connected low impedance (ie not inside metallic conduit) to the earthing electrode (not breaker box). Then hundreds of thousands of joules are not inside hunting for earth destructively via appliances.

If a breaker box 'whole house' protector is connected via a hardwire that goes up over the foundation and down to an electrode, then protection is compromised. Hardwire is too long. Sharp bends exist when going over the foundation. Hardwire is not separated from other non-grounding wires. Plug-in protectors (obviously without earth ground) only did what they claim to do. And may have made damage easier.

Averting future damage starts with inspecting what actually does protection - single point earth ground. Not just any earth ground. World's best protector is useless if not connected low impedance (ie less than 10 feet) to this unique and essential ground. Either by hardwire or via a protector.

Inspect earth ground for both 'secondary' protection layer at your service entrance and a 'primary' protection layer typically on a utility pole. Only earth ground (not any protector) defines each protection layer.

How many never learned this and did not discuss here what has done appliance protection from direct lightning strikes for over 100 years? How many foolishly assumed an adjacent protector or UPS does effective protection? Same protection is needed even if incoming utility wires are underground. A protector is only as effective as its earth ground.

My way of testing ground rod. Because I have a mid height tower for my HAM antenna I need reliable earth grounding. I drive rods few feet apart several of them. I even dump some charcoal powder into the hole for better conduction. Join them altogether with silver plated weaved ground straps by brazing. Then I use light bulb connected between hot AC line and ground to test how good the ground is. When bulb lights up bright, it is good. Also I can measure voltage. From there can estimate ground rod resistance is ~half Ohm. This protects my tower and antenna array. I don't tie it to house ground to prevent ground loop. Common mode current is No, No.
 
Transdector is the gold standard of lightening protection product vendors. You want a surge arrestor versus a surge protector. As far as phone line and cable l-com.com sells inline lightening surge arrestors with gas discharge tubes depending upon your application.

IF you have had repeated strikes I would recommend getting an electrical contractor out there and make sure that the builder did not cheat on the grounding/earthing rod by hitting a rock and then cutting off 5 feet of copper rod to hide the inadequate grounding. Repeated surges like you describe are usually caused by inadequate grounding or a break some where.

Read up on the requirements for earthing in the most current version of the National Electric Code and your local building codes to make sure you know what you are talking about when you ask an electrical contractor comes out.

Alternately read up on the grounding efforts HAM radio operators have to go through on their antennas and equipment and you may have better results on finding products that will help you going forward.

If you really, want to read up on the subject check out www.timebomb2000.com and read up on the many EMP/HEMP/HPM threads that exist there.
 
instead of extremely pricey surge protection the best surge protection is a capacitor in series. If the surge is too much it will blow up the capacitor so it will act as a fuse and a noise filter. A capacitor does the smoothing immediately. This would be placed at the start of the DC circuit so it would protect the device
 
You can protect networking ports from lightning but they shouldnt be with the same surge protector box as your plugs are because lightning when you have breakers, fuses, exploding capacitors the lightning remains as static electricity so they can jump to other things.
Demonstrates why surge damage is often directly traceable to a human who knows without first learning even how electricity works.

Lightning is an electrical current. Or more specifically, a current source. That means voltage will increase as necessary so that current will flow. Static electricity is a static charge that remains charged because no current flows. Lightning is not static electricity.

Second, a wall receptacle third pin is safety ground (or equipment ground); not earth ground. Completely irrelevant to surge protection which is about earth ground.

Furthermore, earth ground must earth the transient current (surge) - not its victim (an appliance).

Third, normal is for a transient to pass through many devices to get to earth. It may damage one or a few internal components. Definitely not damage all internal parts; for obvious reasons. A direct strike that will damage or explode every part is wild speculation also known as junk science reasoning.

Fourth, in the OP's event, a potential outgoing connection from computer to earth was obvious. NIC card, via ethernet cable to router, then through modem, and finally to earth ground. Incoming path would be a typical one - AC mains.

Robust protection is provided by a PSU - especially a switching PSUs. For example, to create rock stable, low DC voltages, a switching supply first converts income AC power into radio frequency spikes that well exceed 300 volts. Same circuits that convert highest voltage spikes into 3, 5, or 12 volts also provides robust protection from surges.

PSUs have a high tolerance for surges. Design standards for 120 volt electronics define protection at or exceeding 600 volts. But an adjacent protector can bypass that protection; connect a surge direct into electronics.

That surge that is incoming on AC mains could be outgoing to earth via a network port. Outgoing to earth destructively via a router or modem.

Same surge was incoming to all other appliances. But since that surge found a best connection to earth via networking equipment, then a surge needed no outgoing and destructive path via other appliances. As detailed previously.

Fifth, this is obvious. Damage occurred because a human mistake existed. Lightning uses that mistake to be inside; to hunt for earth destructively via appliances.

Protection from direct lightning strikes is easy - typically costs about $1 per protected appliance. Hard part is unlearning popular myths. Then properly earth a 'whole house' protector rather than spend tens or 100 times more money on near zero joule, plug-in protectors.

Sixth, others discussed examples of bad earthing. Earthing that meets current safety codes (National Electrical Code) may be insufficient for surge protection. Concepts such as equipotential and conductivity apply. Earthing (not a protector) and its connection (ie low impedance) for every incoming utility wire defines protection.

OP asked for effective protection. Best protection at an appliance is already inside that appliance. A transient that can overwhelm existing protection must be earthed BEFORE entering a structure. Typically costs about $1 per protected appliance using principles demonstrated by Franklin more than 250 years ago. Hardware for this is available in Lowes, Home Depot, and any electrical supply house.
 
instead of extremely pricey surge protection the best surge protection is a capacitor in series. If the surge is too much it will blow up the capacitor so it will act as a fuse and a noise filter.
First, if that worked, then all appliances already have best protection many times over.

Second, that myth violates even what Franklin demonstrated in 1752. A surge is a current source. That means voltage increases as necessary to blow through anything that foolishly tries to stop it. How does a centimeter capacitor stop what three miles of sky could not? Please learn the science call electricity.

Third, if a surge is incoming to that capacitor, then same current at the same time is also outgoing from that capacitor. It is called electricity. That means same current is also passing through appliances that a series capacitor is suppose to protect - at the same time.

Fourth, surges are done in microseconds. Nothing (not even a fuse) will 'block' that current. Damaged part or a blown fuse does not open until long after the surge is finished and done. Surge is done in microseconds. Time for a fuse or capacitor to disconnect (block) is milliseconds or longer.

Capacitor speculation is bogus for more than four reasons. Simple electrical concepts must be remembered before making protection recommendations.

If a surge is incoming to a protector, then same current at the same time is also passing through attached appliance(s). Obvious when one remembers lessons from school science.

Protection was always about connecting to earth BEFORE that current can enter a building. As was well understood over 100 years ago.
 

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