RANT: Lightning strike close to my house killed my electronics!

[street]

With lighting and surge protection you want the protection upstream before it enters the breaker box. At least having protection before it enters the box it can weaken the event. That is why having the protection at the meter where it enters your home from power supplier is more beneficial if an event does occur. It is still okay to have a surge protector in the breaker box itself.

Some of those all home surge protector devices that are installed only protect one circuit of your home. Home owners think all circuits are protected in their but sometimes that isn't the case.

 

[Car-Guy]

Several years ago, I was looking out the front window during a bad electrical storm and I saw lighting hit one of my big oak tress (about 150 yards from the house) This was a 40+ year old tree that was probably 60 to 70ft tall. The strike shook it like a rag doll... After the storm past , I walked over to the tree and saw that the lightning had knocked off all the bark from the tree... Very strange to see... Anyway the tree died and I cut it down the next year.

But I do agree with those who have mentioned surge protectors and/or UPS's.... I have two small UPS unit's. One for my home entertainment system and one in my office that has my main computer, router, etc. Not only does it protect my sensitive electronics from surges, (and dips and noise) but it allows us to ride out short outages... The UPS's will keep everything running for 30 mins to a hour....If the commercial power outage last more that 5 minutes, I just fire up the generators well before the UPS's die...

Been doing this for more than a decade now and my electronics have been VERY stable and reliable.

 

[Mr._Graybeard]

I have a surge protector wired into the breaker box as well as lightning rods on the roof. Some years ago my neighbor, a farmer, lost his machine shed and several hundred thousand dollars worth of equipment when lightning struck it and set it on fire.

 

[ncbill]

Same thing as OP happened to a neighbor with a close lightning strike that traveled down the DirecTV cable, destroyed the receiver, & blew out their TV as well...they could smell smoke inside the house.

 

[pacergal]

OP--sorry that happened to you and your electronics.

We had a whole house surge protector installed last year, and have surge protectors on all electronics in the house, too. Hopefully, will never need to see if it works or not......

 

[ivinsfan]

Same thing as OP happened to a neighbor with a close lightning strike that traveled down the DirecTV cable, destroyed the receiver, & blew out their TV as well...they could smell smoke inside the house.

BIL house actually had a fire start but it caused minimal damage as they spotted it immediately.

 

[Walt34]

Despite having a whole house surge protector AND another one on the computer, several years ago a nearby lightning strike took out the motherboard in the PC, all the smoke detectors (they're hardwired) the main board on the furnace and A/C, the oven igniter, two of the remote controllers/switches on ceiling fans, and a couple of other items I can't remember now.

The whole house surge protector (in this case leased from Potomac Edison) covered all but the PC motherboard, to the tune of about $900. The paperwork was a PITA though.

So while surge protectors no doubt help, they are by no means a guarantee.

 

[Texas Proud]

One thing to think about... surge protectors do not last forever... not sure how long but I have read over time they are less effective...


I would think about changing out ones you have if you had a lightning strike close to your house...

 

[westom]

I have had a couple of the UPS units get fried during storms and power outages, but what was plugged in to them has never suffered any damage - they did their job.

A conclusion that works when observation, combined with wild speculation, creates a conclusion.

Start with how electricity works. If a surge is incoming to that UPS, then at the exact same time, that current is also outgoing into attached appliances. Only urban myths claim an electric can be incoming and have no outgoing path.

Second, learn relevant numbers. Electronics will routinely convert a thousands joule surge into low DC voltages that safely power semiconductors. How many joules will destroy a UPS? Always read specification numbers. Hundreds?

A surge too tiny to overwhelm best protection inside electronics also destroyed that tiny hundreds joule UPS.

Grossly undersizing protection inside that UPS means wild speculation (no numbers) recommended the UPS.

If that UPS was doing something useful, they why were so many less robust appliances unharmed? What was protecting a dishwasher, digital clocks, furnace, GFCIs, recharging electronics, LED & CFL bulbs, refrigerator, doorbell, central air, and smoke detectors? Were those on invisible UPSes?

No facts justify that UPS recommendation. If its joule number was any smaller, then it would be zero. Just enough above zero to claim 100% protection - subjectively. Its protection numbers are inferior even to strip protectors. Subjectively: first indication of a scam.

Effective protection always answers this question. Where do hundreds of thousands of joules harmlessly dissipate? UPS will not even discuss it. Since their target market are naive consumers ... who ignore all numbers.

Hundreds of thousands of joules can only dissipate harmlessly outside. Protection only exists when a surge dissipates outside in earth. Protection only exists when a surge is not anywhere inside.

A 'whole house' protector does that. Effective protection means no damage from any surge - including direct lightning strikes. The numbers?

Lightning is typically 20,000 amps. So a minimal 'whole house' protector is 50,000 amps. Ineffective protectors do no protection - fail. Effective protectors remain functional for many decades after many direct lightning strikes.

That is only protector life expectancy over many surges and many years. Protection during each surge is defined by the only items that dissipates that energy - single point earth ground. A protector is only a connecting device to what requires most attention. To what defines all protection. A 'whole house' protector connects low impedance (ie less than 10 feet) to electrodes that both meet and exceed code requirements. Only then are all appliances (especially a minuscule joule UPS) protected.

Plug-in protectors have no earth ground. And for good reason. They are only Type 3. Must connect more than 30 feet from the main breaker box and earth ground to lessen failure - and fire. Only Type 1 and Type 2 protectors can connect low impedance (ie less than 10 feet) to the other item that does all protection - earthing electrodes.

Nothing new here. Franklin demonstrated this well understood concept over 250 years ago. Earthing surges (including lightning) has been standard over 100 years ago in facilities that cannot have damage.

Effective protection only exists when a protector does not fail. And when hundreds of thousands of joules dissipate harmlessly outside in earth. Once inside, then nothing will avert a hunt for earth ground destructively via household appliances.

A protector is only as effective as its low impedance connection to and quality of earthing electrodes. Those (and not a protector) require most attention.

 

[westom]

Despite having a whole house surge protector AND another one on the computer, several years ago a nearby lightning strike took out the motherboard in the PC, all the smoke detectors (they're hardwired) the main board on the furnace and A/C, the oven igniter, two of the remote controllers/switches on ceiling fans, and a couple of other items I can't remember now.

Damage means a protector was improperly installed. Damage only happens when human mistakes make that damage possible.

An investigation starts with the only item that does protection. A low impedance (ie less than 10 foot) connection to and the quality of earth ground electrodes.

For example, if an earth ground wire from breaker box to electrodes goes over a foundation, then impedance is excessive. Wire is too long. Sharp bends over a foundation further increase impedance (decrease protection). That hardwire also must be separated from other earthing wires. Human mistakes must be located and corrected.

Those earthing electrodes are only the 'secondary' protection layer. Each protection layer is defined by an earth ground. Also inspect your 'primary' protection layer. Utility equipment also must have hardwires that connect to earth - your 'primary' protection layer. Copper thieves routinely steal wire - compromising protection.

Was it single point earth ground? All four words have electrical significance. An AC utility demonstrates this [single point earth ground concept](https://www.duke-energy.com/energy-education/power-quality/tech-tips) using good, bad, and ugly (preferred, wrong, and right) examples in Tech Tip 8. A 'wrong' installation explains damage directly traceable to human mistakes. Properly installed 'whole house' protector means no surge damage - even from direct lightning strikes.

Plenty more to discuss to define 'properly installed'. 'Whole house' protection means nobody even knew a surge existed. Protector is only a connecting device to what does all protection.

 

[gamboolman]

We have lived along the Gulf Coast, SE Texas, Mobile, Alabama, Slidell, Louisiana and in Equatorial Guinea & Nigeria West Africa

Folks getting computers, TV's and Appliances destroyed happens a good bit all along the Gulf Coast. We lost a few appliances and computers over the years. As I recall, it seemed like in Mobile, AL there was alot of damage from Lightning the few years we were there when I was working at Mobile Bay for Mobil before Exxon bought Mobil.

In Africa, the lightning would cause outages at the Compound(s) quite regularly during the Wet Season. We used to get some hellacious storms and lightning in Port Harcourt and Eket in Nigeria.

Offshore the lightning strikes were bad and could cause issues.

If we ever build a "Custom House" - we will see can we get the Protection detailed out by westom in his post above.

 

[ExFlyBoy5]

A conclusion .../SNIP/

Welcome to the forum, Westom. You should come out of the shadowy alley ways of the internet and introduce yourself.

 

[statsman]

When we were at the design center picking out options for our house that was being built here in Central Texas, the electrician tried to get us to purchase a whole house surge protection package. We passed on it, based on our experiences back in California and the cost of the package ($$$$). After having had a few lightning strikes close to our new house now, I think that might have been a mistake.

Anyway, the electrician described a situation where someone he knew had a lightning strike on their house that traveled through the internal Ethernet network. Apparently, several electronics attached to the network were lost. Additionally, the cable connections at the Ethernet jack outlets had fused together. They had to remove the entire Ethernet jack outlets and replace them.

 

[youbet]

I had a friend who was talking on his ham radio when lightning hit his antenna, traveled down the antenna cable to the radio, and sent him flying backward into the wall. The only injuries were from hitting the wall, but he spent the night in the hospital and took over a month to fully recover.

After that experience, he got into the habit of disconnecting his antenna cables before every thunderstorm. I would have, too!

Disconnecting and grounding feedlines for ham radio antennas when they aren't being used is best. Because most hf ham antennas are large, they can collect enough static to damage equipment even without actual lightning discharge occurring close by. I recall sitting in my living room and hearing a snapping sound coming from the den every few seconds. I walked in there and the sound was coming from my antenna tuner. What da heck?

The antenna was a dipole 135' long, center fed with open wire line. The open wire line was attached to my Johnson Matchbox antenna tuner and from there to my equipment. Apparently enough voltage was being induced into the antenna that it would build up to the point of sparking across the plates of one of the variable capacitors in the antenna tuner periodically. Not good!

This occurred in late afternoon on an overcast day with lots of dark clouds and a breeze. It hadn't started to rain yet. No lightning or thunder taking place.

After that I installed a large dpdt knife switch outside and used that to ground the feedline when I was using the antenna!

 

[westom]

If we ever build a "Custom House" - we will see can we get the Protection detailed out by westom in his post above.

Protection starts when the footing are poured. Ufer grounds were originally developed so that lightning does not cause explosions in munitions dumps. A radio station describes how he used Ufer grounds to properly earth (http://scott-inc.com/html/ufer.htm) a transmitter.

Another demonstrated how this is done in FL (http://www.gfretwell.com/electrical/ufer.jpg) where lightning is an even greater problem.

 

[westom]

the electrician tried to get us to purchase a whole house surge protection package. We passed on it, based on our experiences back in California and the cost of the package ($$$$)

Such protection is installed in any house today (even so old as to only have two prong receptacles) for about $1 per protected appliance.

Compare that to $25 or $80 for each plug-in protector to only protect one appliance. And not even do effective protection. Those protect profit margins; not appliances.

That surge would be traveling through a network because that is a best, outgoing path into earth. Network is rarely an incoming path due to robust protection required to be on every TV cable, telephone, and satellite dish. Since those wires already have best protection, then those are is a best outgoing path to earth. Damage is typically on an outgoing path from appliances.

Incoming path is typically AC electric. Only wires not required to have effective protection. Incoming path is less often damaged.

 

[ERD50]

Thanks for bringing this up. I will be hiring a licensed electrician sometime in the future when I complete my list of changes I want for the home we moved into this year. Mostly for three added circuits in the furnace/storage room I converted to my workshop (two for future electric brewery), with added outlets along two walls.

So I'll purchase one of these whole house surge protectors, and have the pro install it with the other changes. I could/would do it myself, but I want no issues with DIY changes when we sell. I've seen recommendations that the surge protector get its own 50A breaker at the top slot, closest to incoming power, so that also involves moving a couple breakers down to the bottom.

I'll also check the ground rod (I'll have to read up on how to approach that one), and whether the incoming cable/internet is properly grounded.

OK, I did some reading, and it looks like the spec is < 25 Ohms for a ground rod. That seems very high to me. Just 4 Amps would raise everything 100V above 'ground'. Looks like the way to test this w/o special equipment is to take a 25 Ohm R (I'll likely use 4-100W bulbs in parallel), measure current when connected hot-neutral, verify R = E/I. Then (carefully!) connect those bulbs from hot to the ground rod, measure current, and calculate the total R. Ground rod R will be total R - bulb R (though bulb R will vary a bit with changes in current, but I can adjust for that with measurements on a dimmer if needed). I'd start with lower currents first, in case the connection is really bad.

I had a friend who was talking on his ham radio when lightning hit his antenna, traveled down the antenna cable to the radio, and sent him flying backward into the wall. The only injuries were from hitting the wall, but he spent the night in the hospital and took over a month to fully recover.

After that experience, he got into the habit of disconnecting his antenna cables before every thunderstorm. I would have, too!

Disconnecting and grounding feedlines for ham radio antennas when they aren't being used is best. Because most hf ham antennas are large, they can collect enough static to damage equipment even without actual lightning discharge occurring close by. I recall sitting in my living room and hearing a snapping sound coming from the den every few seconds. I walked in there and the sound was coming from my antenna tuner. What da heck? ....

This occurred in late afternoon on an overcast day with lots of dark clouds and a breeze. It hadn't started to rain yet. No lightning or thunder taking place.

After that I installed a large dpdt knife switch outside and used that to ground the feedline when I was using the antenna!

Check this video:

I know you said it wasn't raining, so not totally applicable, but he found that snowflakes would accumulate enough charge to cause arcing at the connection. Each flake adds a bit of charge, and they add up with no place to go! I'd also think a large Ohm bleeder resistor would help keep static from adding up, and have negligible effect on the cable characteristic impedance.

In any case, the big knife switch is a good idea. I've also sometimes just unplugged some of my expensive and/or hard to replace electronics when a storm is approaching. If the surge can jump 6' to the plug laying on the floor, I'll probably have bigger problems!

-ERD50

 

[old medic]

I know your pain.... but consider yourself lucky.... Our ZAP ended up with a insurance check for nearly $10K in electrical damage... every delicate electronic... computers, Audio/video, fridges....several surge protectors... every ground fault outlet in the house..
took over a month to sort everything out. lost a ton of food not covered...

 

[ERD50]

Related to all this, and is also a bit of a rant - I get a bit worked up when I see what appear to be knowledgeable people claim that those little plug in testers with the three neon lights can tell you that you have a "good ground".

They tell you that you have a ground. They do not tell you that the ground is "good". It takes very little current to light up that neon bulb, you need to load that circuit to verify that.

The quick/dirty way I test for "good" grounds is with a 100W light bulb with a couple wires attached to its socket, with ~ 1/2 bare ends. Carefully stick one wire into the ground hole, then touch the other wire to the hot blade slot. The bulb should light steady and bright. Best is to verify the voltage on the bulb is the same as from hot-neutral, or verify the current is the same. But this at least tells you that the ground can support 1 amp of current, rather than ~ 0.001 amp that a neon lamp will draw. I should probably actually wire up a plug and switch this way to make it more convenient.

-ERD50

 

[sengsational]

^I'm confused about that test. When I look in my panel, I see all the neutrals and grounds are connected. So hot to neutral and hot to ground would be the same. I guess you're putting that small amperage through a bare wire vs a white insulated one, but both wires are the same diameter.

 

[CRLLS]

^I'm confused about that test. When I look in my panel, I see all the neutrals and grounds are connected. So hot to neutral and hot to ground would be the same. I guess you're putting that small amperage through a bare wire vs a white insulated one, but both wires are the same diameter.

Not all grounds inside the house are connected back the the service panel via a wire. Some just use the conduit or armored cable sheathing. Not all receptacles have a ground wire connected. Many in-use use the mounting screw to the box as the ground connection. That test will help to determine if the ground from your outlet to the box are functional. I am happy with just using a plug-in tester that tells if things are wired correctly such as the Ground is connected and if the White and Black wires are reversed somewhere in the circuit.

 

[ERD50]

^I'm confused about that test. When I look in my panel, I see all the neutrals and grounds are connected. So hot to neutral and hot to ground would be the same. I guess you're putting that small amperage through a bare wire vs a white insulated one, but both wires are the same diameter.

See CRLLS post. But yes, the ground and neutral are connected back at the service panel. This light bulb test helps to verify that the ground connection can handle some current. It is possible for the connection to be just hanging on by a thread, or a very loose screw, enough to light a neon bulb, but not carry the full current as it should if a fault occurs.

If your neutral is poor, you would know because your appliance just wouldn't work, or act flaky. But if the ground is poor, you don't know until a fault occurs and the protection isn't there. Too late!

An example of why good grounding is important: Say you have a 3 prong appliance with some metal casing. If the HOT wire internally somehow comes loose or is bridge by some foreign material to the case (cooking residue that gets burnt and carbonized, and remains conductive- I've seen this happen!), that case is now "HOT" with 120V. But an appliance like that is designed to have that metal case connected to the ground plug.

So with a good ground, all the HOT current goes directly to ground and will usually blow the circuit breaker, protecting you, and making you aware that the appliance has a fault. Even if the bridge doesn't draw enough current to blow the breaker, the metal case is grounded, so you won't get a shock.

But if that ground connection back to the panel is weak, it may not blow the breaker, and it may not keep the case at a safe voltage - it could float up near 120V.

So why have a ground if it is just connected to neutral? It protects against the HOT/NEUTRAL being reversed. If you just relied on Neutral to be zero volts, if HOT/NEUTRAL got reversed (not so uncommon) then that metal case would be connected to HOT, and be a real danger.

Also, since normally there should be no current on the ground, it helps to keep noise from these currents out of audio circuits.

-ERD50

 

[youbet]

I'd also think a large Ohm bleeder resistor would help keep static from adding up, and have negligible effect on the cable characteristic impedance.

Actually what I have begun using is an L to ground where the L value presents a short to DC and a high impedance to RF (at the frequencies I'm using).

I think the problem with using a high value R, as you suggested, is that if there were a direct or nearby lightning strike, The resistor would have to shunt a lot of current to ground. They don't make resistors that will withstand that unless they're wire-wound. And you can't use wire-wound resistors at RF because they add inductance.

Even if you could find a non-inductive resistor (or bank of non-inductive resistors in parallel) to carry large amounts of current, it would likely be very expensive. But you can wind an appropriate inductor out of something like quarter inch copper tubing or #6 solid copper wire.

I've also seen guys use spark plugs from each leg of the feed line to ground.

But I'm no expert. I just followed the instructions in a magazine article. so YMMV. And thanks for posting the video! Very interesting!

 

[ERD50]

Actually what I have begun using is an L to ground where the L value presents a short to DC and a high impedance to RF (at the frequencies I'm using).

I think the problem with using a high value R, as you suggested, is that if there were a direct or nearby lightning strike, The resistor would have to shunt a lot of current to ground. They don't make resistors that will withstand that unless they're wire-wound. And you can't use wire-wound resistors at RF because they add inductance.

Even if you could find a non-inductive resistor (or bank of non-inductive resistors in parallel) to carry large amounts of current, it would likely be very expensive. But you can wind an appropriate inductor out of something like quarter inch copper tubing or #6 solid copper wire.

I've also seen guys use spark plugs from each leg of the feed line to ground.

But I'm no expert. I just followed the instructions in a magazine article. so YMMV. And thanks for posting the video! Very interesting!

Agreed. The resistor isn't going to do any good for a lightening strike, the only thing I was thinking was that it would bleed off static charge. Your use of an inductor with Hi-Z at the frequency of interest would do that too.

The guy in the youtube video does some pretty interesting restoration projects. He has a lot more patience than I do! And a lot more O'Scopes, signal generators, spectrum analyzers, etc, etc, etc!

-ERD50

 

[westom]

Agreed. The resistor isn't going to do any good for a lightening strike, the only thing I was thinking was that it would bleed off static charge. Your use of an inductor with Hi-Z at the frequency of interest would do that too.

And all that is irrelevant to what causes damage.

Static electricity is routinely made irrelevant using an NE-2 neon glow lamp. Even protects sensitive RF amplifier transistors. A less than 1 milliamp conducting through that bulb reduces a voltage from thousands or tens of thousands to less than 60. Static electricity is routinely made irrelevant by what is inside all electronics.

Does not matter if neutral and safety ground connect at one point. Electricity in any two wires is always different at both ends. Such discussions say nothing if relevant numbers are missing.

For example, a neutral wire from a wall receptacle to main breaker box might be 0.2 ohms resistance. And 120 ohms impedance. Resistance is irrelevant. Impedance is why no wire from a receptacle can provide effective protection.

This discussion is about lightning (and other similar currents). What happens when a tiny 100 amp surge current tries to connect to the main breaker box and earth ground? 100 amps times 120 ohms is something less than 12,000 volts. Where is the protection? It only exists in fables when basic electrical concepts are ignored.

Why less than 12,000 volts? And IEEE brochure bluntly demonstrates this problem. A protector in one room simply earthed that transient current 8,000 volts destructively through a TV in an adjacent room. It had to find other paths. Wire impedance says why. It found other (destructive) paths to earth.

A point routinely made by professionals today and over 100 years ago. Protection only exists when that current is nowhere inside. Neither neutral wire nor safety ground wire do anything useful.

Protection only exists when that transient dissipates harmlessly outside. Solution is what Ben Franklin demonstrated over 250 years ago. So that a current does not connect to earth destructively via a structure, then a lightning rod (a connecting device) connects that current harmlessly to earth ground electrodes. So that a current does not connect to earth destructively via any appliance, then a 'whole house' protector (a connecting device) connects that current harmlessly to earth ground electrodes.

In every case, it is about a connection to what does all protection - earth ground.

To be effective, a protector must connect low impedance (ie less than 10 feet) to earth ground. Only Type 1 and Type 2 protectors are robust enough to make that connection. Without threatening human life.

Plug-in protectors and other magic boxes are so minuscule as to be Type 3. That means it must remain more than 30 feet from a main breaker box and earth ground. No low impedance connection to earth means it is not doing effective protection. But at least, it is less likely to do this: https://atlantareefclub.org/boards/...ouse-caught-on-fire-and-my-tank-busted.22936/

Fortunately water put out the fire.

Neutral and safety ground wires are all but disconnected from earth. Safety ground is not earth ground - is electrically different. Critical is a low impedance connection. Only a hardwire can make that low impedance (ie has no sharp bends or splices; neutral and safety ground have many) connection to single point earth ground. Since that is how protection is done in facilities that cannot have damage - even over 100 years ago.