A high end consumer grade surge suppressor might be rated for 1000 joules, and a few thousand amps of peak current.

If lightning directly strikes your house wiring, no amount of surge suppressors are going to save you.

For an idea of what a surge suppressor that can handle the blow of a full on lightning strike looks like, take a look at the units used by utility companies on their high tension lines. Typically they are about a 6" in diameter and often several feet long -- and those units still need to be replaced after a single direct hit! https://www.equipmentimes.com/product/details/Lightning-Arre...

The best thing that you can do to protect yourself in the future is to have a lightning rod network installed on your roof, which will shunt the current from the strike directly to the ground. Otherwise the only failsafe alternative is to completely unplug sensitive equipment (still OK to run from battery but with all ethernet etc cables unplugged -- wireless network only) whenever there is a storm predicted.

They are actually designed to remove charge from the clouds above where the rod is installed.

Static electrons loves to congregate in small places, I.e. the tip of a needle or the edge or fold in a piece of metal (can help the paint job add extra paint to those places it is needed most, bonus!)

Anyway a lightning rod is probably the best protection but yeah the copper would vapourise if it.was actually hit, causing a fire.

[0] https://en.m.wikipedia.org/wiki/Lightning_rod#Europe

How many gigawatts is that? I’ve a car I need to jump start.

Afaik the proper way is having a proper lightning rod together with the aforementioned cascade of surge suppressors. And of course a PE!

Consumer grade suppressors are meant for indirect strikes, overhead lines near you, or a direct hit on your neighbour's house.

Edit: spelling

Lightning (as far as I know) does not have consciousness and is not out to get your computer!

The parent post was talking about putting a automatic switch in between the power supply to the house (ground active neutral) and switching it off when lightning struck, the problem there is that the switch will not do much if the lightning air gaps around it.

Ground is also a relative term for a lightning strike.

When lightning hits the ground, a potential field emanates from that point. The further out the closer to 0V the potential difference is.

As such it depends on where the strike is in comparison to the house, your wiring, where your house is grounded etc.

For example, if the grounding point on your house is very close to the strike, your house ground will be raised to the voltage of that point away from the stike.

The path to 0V may be through your active wiring, your powesupply, the house frame or the water pipes.

So yeah, hope that helps

That is unless are okay buying oil immersed equipment the size of a fridge. And that’s probably not enough, either.

Now here's one for the engineers. We can tell the future. Musicians change tempo before singing the next verse. ADS-B data tells us when there's a plane coming. Could a "smart" surge protector include a measure of ground noise, to sense local charge differentials, and guess that the next spike is probably lightning rather than a typical mains arc? More sensors yes, but increasing protection only when expected would possibly improve the feedback loop.

In modern electronics it's small capacitive gaps that get damaged. Electrolytic capacitors and CMOS gates get their insulation punched through, which destroys the component. As plastic housings have replaced metal ones there's little or no field shielding on gear these days.

As others have said, for prevention your supply circuits should be earthed. They should be anyway, for human health and safety reasons, including an earth rod (long copper pipe or pole driven down into soil at least 1 meter) so your earth return is not too far away. Usually you also want an earth leakage sensor set to cut the supply if any current is flowing through the earth circuit - very useful in a damp/rainy environment.

Problem is; most switched mode PSUs use only the active pair (live and neutral in single phase European terminology) so there's nowhere for errant currents to go. Often they have an arrestor, as old copper telephone systems did, and the idea is that it arcs across, closes the arrestor and shorts the path (often blowing a fuse). With nearby lightning you get >100kV very fast, and it all happens too quick.

In the case where your power is derived from another property as you describe, in the UK we would normally call this a ‘TT’ power supply which you can google. It is absolutely essential (life and death) to have both a good grounding rod and an RCD at your end.

A others have said, get an electrician who understands the subtleties of outbuilding power supplies. If you cannot do that for whatever reason, I suggest first reading up extensively on the different kinds of earthing system, and finding out which one you effectively have.

Since you had no ground previously, it is likely that just live and neutral have been exported from your neighbours property (TT). You can probably check this by visual inspection, and it isn’t actually a problem provided you fix the grounding and protection at your end. To fix this grounding problem what happened? Did the electrician install a grounding rod? Did they happen to measure the impedance of it and write that somewhere? Do you have an RCD in your consumer unit (fuse box)?

Do you have a lightning rod on the house? If not, you absolutely need one, and you have to make sure it has a proper grounding rod. If you don't know if the one that is there is reliable, put in a new one.

> It goes in to the owners house, where the meter is. From there they have pulled a 200 meter cable into ours.

... and let me guess there is no grounding connection at your house but only at the owner's house?

> Any suggestions on what to do next? A big metal stick somewhere in the garden?

For starters - I'll base it on German standards:

- generally, get a licensed electrician on site to review your whole electric installation. It may be severely damaged (e.g. by overvoltage breaking down the isolation of the wires)!

- both your house and the owner's house each need a proper, separate grounding rod for the electrical system. The closer to the house, the better. In Germany, it's standard practice to have one horizontal rod below the foundation and a separate vertical deep-going rod. You can have the electrician measure the quality of the grounding.

- both your house and the owner's house each need lightning rod(s) on the roof connected to the building's grounding rod

- your surge protector in the UPS isn't able to take a full lightning strike, which is why lightning protection usually needs three stages: the first one made out of spark gaps is directly at the point where the electric supply line enters the house, it will take out the brunt of the lightning strike but still leave a dangerously high overvoltage. The second stage is in the distribution cabinet, here varistors are used. The third stage is your UPS's SPD. And it will always need all three stages to work - leave one out and the system becomes useless!

- you also need lightning protection for the phone line and the TV antenna. In the latter case you need to protect the antenna itself by attaching the mast to the lightning rod and the antenna cable / distributor with an appropriate SPD system.

I'm guessing your electrician connected your ground wire to the roof, or some other part of your house construction. That gives you a nice path for lightning to go between the utility neutral and your roof through your appliances.

Umm. When electrician installed grounding rod for me, he did measurements. He couldn't tell how much grounding rods will I need. Because some get lucky and get tapped into undeground water and immediately gets low resistance.

In my case, we couldn't use a single spot as the rods were too hard to go in for required length, so 4 places actually were used and connected together while appropriate resistance was achieved.

Moreover, I don't much about it but someone may approve/reject the following I heard from another electrician: If your ground provides VERY LOW resistance, then it is also bad, because it can work backwards, providing a path from outside to your house.

You need to be careful about this. In many places the depth of the water table varies a lot depending on the season of the year.

Generally it sounds like your electrician was correctly following a well designed code of practice.

Regarding what the other electrician said, for current to flow there needs to be a potential difference and a circuit. In this case your house (roof, frame, etc) is very well connected to the ground it sits on. If it's a long way from your house to the transformer, with exposed overhead power lines, there could be a potential difference with those.

This is where the "level 2" (building entry point) protection mentioned by another commenter comes in. It used to involve fuse(s), heavy duty spark gap(s) and heavy duty varistor(s). I don't know about these days, but I wouldn't trust anything with active control to continue to protect after a lighting strike. Or during it.

Once you got that, pull a ground wire to your panel as well and install a surge protector. This goes after the main switch, before any RCD. (It basically passes any surge into the ground, tripping the main switch if big enough.)

Then install RCDs, if you don't have any. They'll trip if the power pulled from live and neutral somehow mismatches. Which ones to get depends on your type of panel and loads.

It's just a metal rod from the tallest bit of your building to the ground. It can be installed without much specialist skill, so should be cheap.

With that, the rest of your electrics will be fine in the future.

To repair your outlets, call a local electrician. It will probably just require a new breaker in the fusebox (breakers get damaged if lightning levels of current flow through them, then then they will refuse to turn on). The PSU is probably repairable if you find an electronics guy - it will need new diodes right at the input. Maybe a new fusable resistor too. But if youre paying USA labour rates, it's cheaper to just buy a new PSU.

IMMEDIATELY turn off the power at the main circuit breaker.

NEXT, get a registered/bonded electrician to thoroughly inspect and test your building's power feed, its circuits, its grounding, and its surge protection equipment.

Until you do this, your building is a fire trap waiting to strike.

The building's surge/overvoltage protective devices should all be replaced, or some installed if there weren't any.

Some or all of the wiring may need to be replaced if its insulation was crisped.

Next, get all your electrical appliances checked for safety.

You can often see this even with your regular mains voltage, especially if you have some inductive load (anything with a transformer) attached. A small spark arc is visible when you flick the switch.

I’m now in the process of finishing my new all concrete house with 12” solid walls lol. Screw lightning. It’s not a rational reaction, but it’s my reaction.

Keep in mind: surge protectors and UPSes are not necessarily going to prevent damage directly caused by lightning. Lightning has a lot of energy and is high frequency and can make its own paths to ground through and around protective devices.

Lightning strikes cause power outages in a larger area. When power returns, you can get a high voltage surge. This is what surge protection suppresses and protects against.

I guess the fourier transform of that includes plenty of high frequency.

Sounds like a perfectly cromulent outcome to me, if accurate, you're actually pretty lucky.

If your hard disk is a magnetic one rather than an SSD, it's possible that the data will have survived, even if the electronics died. HD retrieval companies work by swapping the media with a working device of the exact same model.

The apartment has a circuit breaker (which tripped) and I have a surge protector as well.

Did some research and read that a Surge protector with "Catastrophic Event protection" feature would have helped. This feature fries the surge protector instead of the equipment connected to it. A note from the mfr of the product I am considering buying: "most surge suppressors continue to let power through even after circuits have been damaged, leaving your equipment exposed to other damaging surges." The surge protector I have does mention that power will pass thru it, if power surge is more than what the suppressor can handle. HTH.

To emphasize tuatoro's points, it appears some of your branch circuits were damaged by the strike. Their wiring needs to be inspected to see if the insulation was compromised. If yes, the wiring needs to be replaced. The dead kitchen appliances need to be evaluated for safety -- they could now be an electrocution risk.

Many of the comments display a dangerous (and common) misunderstanding of the purpose of a grounding rod. The language used for this topic is confusing, which doesn't help.

The important thing to know is: A GROUNDING ROD IS NOT A SAFETY GROUND.

Article 250 of the US National Electric Code covers "grounding" and "bonding." Note the two different words. "Grounding" (connect to earth) is done to limit voltage induced by lightening, line surges, or unintentional contact with higher-voltage lines.

"Bonding" is the connecting metal parts of enclosures, cases, and equipment to the supply source via an effective ground-fault current path. Bonding is what provides safety. This is what most people think of as the green "grounding" wire (in the code, called the "equipment grounding conductor."

Note it says "to the supply source." In your case, the source is the house 200 m away feeding your panel. The cable from that house should be 4 or 5 conductors, one of which is the equipment grounding conductor ("ground wire"). If the cable does not include the equipment grounding conductor, the cable MUST be replaced. It is not safe to run a separate wire back for the grounding conductor.

See this document on article 250 requirements:

https://www.mikeholt.com/instructor2/img/product/pdf/20NCT2-...

Thailand has 230 V / 50 Hz service, but the grounding and bonding principles are the same.

Dude. Install a lightning rod.

For everything else - you need an electrician. It's not as easy as just a "big metal stick somewhere in the garden" -- get someone (else) out to actually inspect and deal with it. The reason being is that IMO: your surge protection devices shouldn't have fried if they were properly grounded. So the previous electricians might not have properly grounded your property.

Lightning is not generally possible to protect against in nonconducting residential structures except with lightning rods and other devices designed to divert the strike. Even then the protection is not complete. Steel clad steel buildings are exceptionally resistant, but even in this ideal case, a direct strike can destroy equipment through the EMP and differing potentials generated within the structure.

Lightning protection is a achieved through defense in depth. Utility level, distribution level, then a protector at the service entrance, then circuit protection, then outlet (plug in) protection, then in device protection. If the lightning skips any of these steps by striking inside of these rings of protection, anything inside is going to face extreme challenges and is very likely to be damaged. You can’t trivially absorb or divert 10-1000 terawatts of power. It’s enough to heat air to 20,000c and to instantly vaporize a third of a cubic meter of sand. You just can’t easily protect against that kind of energy. It’s equivalent to protecting your house from suffering damage if a small commuter aircraft crashed into it.

It’s possible, but it requires extreme measures… not just plugging something into an outlet.

I had this happen to me, but I think it hit a phone line (back in the ADSL days) - and it caught more components then I initial thought, the ones that went under the radar were the RAMs.

The symptom was decompressing RAR files, sometimes it would give errors. The HDD also started to act oddly, so you should probably run some tests to see if everything is ok.

Get. An. Electrician.

There's a lot to be said for countries with decent certification systems for electricians and I'm pretty sure Thailand doesn't come close to having that.

OK fine, but what exactly is the poster expecting from the HN community ?

Nobody competent should be giving the guy advice without a site inspection.

In Thailand I'm willing to bet electricians aren't licensed and you're going to gamble if the local electrician you call has the ability to problem solve issues like this.

https://www.thisoldhouse.com/electrical/21194149/how-effecti...