Surge Protector vs Lightning Strike

[GotNoRice]

Is there any kind of surge protector out there that can actually protect against a lightning strike? If not, is there anything that can be done? Does it even matter to try?

I've heard some say that the only way to actually protect anything is to actually unplug it during the storm.

One thing I really love to do during an intense storm is to play music loud on my large stereo. It's one of the few times when you know that you can play music as loud as you want to without even the slightest fear of upsetting your neighbors (too much background noise from the storm). But of course, actually using my stereo during the storm is the opposite of having it unplugged. I'm less worried about my computer vs my stereo because I already build a new computer every few years, whereas most of my stereo components are older than I am.

 

[Lt Broccoli]

Get a big UPS for your stereo, disable the beep, and unplug it during a storm

 

[GotNoRice]

I'm not sure if that would work. I have to turn each of my power amps on one at a time or the inrush current will trip the circuit breaker. Power consumption (measured via kill-a-watt) with everything on but volume control at minimum is about 550w, and about 1400-1600w when I have it very loud. I would need to keep the computer on also, as it is my main source. So that would be another 300+ watts.

 

[michalrz]

Plus you could get all sorts of noise problems if the battery output is poorly regulated.

If a bolt actually touched down on your house and traverse to ground via walls and such a lot of devices could die even when disconnected because of induction.

You'd probably want to start by placing a hefty surge protection strip in line. Learn how to read the specs first - you need to check how many Joules (hundreds/thousands - 600 would be the bare minimum) it can withstand between each line of your power cable (not just the 'hot' one!). You also want one with a high amperage pulse rating - at least something like 15 thousand amps or more. Redundant breakers are nice.

 

[michalrz]

Also I might be horribly wrong but isolating your gear from walls and floors using rubber feet or what not might help - the wandering current won't be able to establish a low impedance path to ground via the devices' chassis.

 

[niqht]

Honestly, if you get a really close strike there is nothing you can do about it.
The millions of volts just jumped the 1000+ ft from the sky, your few inches/feet and electronics mean nothing.
If it's gonna happen... it just is.

 

[michalrz]

I work at a firm that is located on the ground floor of a rather large office building and in 2009 a lightning bolt had hit a tower nearby, like 200 metres away. People literally kneeled down, jumped, ran away screaming.
And just like that - a 60 metre long video cable with a live CCTV feed had degraded so badly I had to waste a day replacing it.

 

[Nasgul]

None. No such thing, I had a $500 surge protector for my home theater system and the damn thing was useless. Lighting hit the tree in my back yards, 23-25 feet away and everything was fried, TV, DVD player, Receiver was working except for the sub-output.

I got it all replaced and taken care of in the end, but it sucks when your stuff is fried.


Lighting.......nothing will stop it.

 

[evilsofa]

This page covers pretty well what you're dealing with in trying to protect yourself against lightning strikes.

If lightning strikes are a thing in your area, offsite backups should be a thing for your PCs.

 

[iroc409]

I've pretty much switched to all Isobars. I've had good luck with them, and they have filters in them. I've even started to move away from UPS units on all but the servers/networking. Most of the cheaper UPS units don't provide a lot of protection, and compromise a bit in their on-battery power. The power supplies in most computers will regulate voltage fluctuations within most of the limits of a basic output-limiting UPS as well. The power in our neighborhood is very stable, however. In the past I've lived in places with very unstable power, and UPS units were a must.

But, as said, it's really hard to stop lighting. If you think about it, it's electricity that is arcing thousands of feet in an air gap. There's not much you're going to do to stop it.

 

[cyclone3d]

I've pretty much switched to all Isobars. I've had good luck with them, and they have filters in them. I've even started to move away from UPS units on all but the servers/networking. Most of the cheaper UPS units don't provide a lot of protection, and compromise a bit in their on-battery power. The power supplies in most computers will regulate voltage fluctuations within most of the limits of a basic output-limiting UPS as well. The power in our neighborhood is very stable, however. In the past I've lived in places with very unstable power, and UPS units were a must.

But, as said, it's really hard to stop lighting. If you think about it, it's electricity that is arcing thousands of feet in an air gap. There's not much you're going to do to stop it.

But once it hits the ground, power pole, cable line, etc, it is going to take the path of least resistance.

In which case, unplugging everything should take care of it.. hopefully.

The problem with ground in wiring is that it is a straight short to earth ground pretty much all of the time no matter what "protection" you have in between your electronics and the outlet.

Now if you had a nice big diode in line to keep the power from coming up through the ground.. it might help, but I am pretty sure that that would make the ground technically not work as intended.

 

[westom]

Is there any kind of surge protector out there that can actually protect against a lightning strike? If not, is there anything that can be done? Does it even matter to try?.

Your telco's $multi-million switching computer connects to all other buildings. Therefore it will suffer about 100 surges with each storm. So they disconnect phone service before each storm? Of course not. Protection even from direct lightning strikes has been routinely done for well over 100 years. And (due to advertising) is unknown to most consumers.

You can install same for about $1 per protected appliance. But it means learning some concepts originally introduced in elementary school science (ie Ben Franklin's lightning rod).

A typical surge (ie lightning) is an electrical current that connects a cloud (three miles up) to earthborne charges (four miles distant). Protection has always been this simple. That current path must be on conductors that always remain outside the building. Nothing inside (ie Isobar) will provide protection (except from surges that typically do not cause damage). Read manufacturer specification numbers. Even those do not claim protection. How many joules does the Isobar claim to absorb?

Any wire that enters a building must first connect low impedance (ie less than 10 feet) to single point earth ground. Then a direct lightning strike far down the street need not be inside hunting for earth destructively via appliances. Then nobody even knows a surge existed.

Best protection on a TV coax cable is a hardwire from that cable to single point earth ground - as required by codes generations ago. Any surge on that coax connects to earth BEFORE entering. Therefore no surge current is inside a building - no damage.

Telephone wire cannot connect directly to earth So a 'whole house' protector makes that connection. Also required by codes long before any of use existed. And installed for free.

Does that protector do protection? Of course not. No protector does protection. Effective protectors connect low impedance (ie wire without any sharp bends) to single point earth ground BEFORE entering. Then direct lightning strikes connect to earthborne charges maybe four miles away without damaging anything inside a house.

Most common source of damage is AC mains. A direct lightning strike far down the street is a direct strike incoming to every appliance. So all appliances are damaged? Of course not. Only damaged is an appliance that also has an outgoing path to earth ground. For example, a strike incoming to the TV on AC mains will be outgoing to earth via the coax or HDMI port. Damage is often on the outgoing path; not on an incoming path. Then naive consumers want to blame the coax.

Cable companies strongly discourage protectors on their cable for a long list of reasons. Including best protection is already installed for free. Your damage is directly traceable to AC mains that were not connected low impedance (ie less than 10 feet) to single point earth ground. A defect that exists today in almost every home doe to so many homeowners who never learned this stuff.

Whole house protectors come from companies with better integrity including Square D, General Electric, Polyphaser (an industry benchmark), Ditek, Intermatic ABB, Syscom, Levition, and Siemens ... to name but a few. Cutler Hammer solutons are found in Lowes and Home Depot. Clearly not listed are Isobar, Monster, APC, Belkin, Tripplite or Panamax. Those protectors have no dedicated and low impedance connection to earth. Those protectors will not discuss where hundreds of thousands of joules harmlessly dissipate.

Useful answers also provide critically important numbers. For example, the ground wire from breaker box to earthing electrode has excessive impedance if it goes up over the foundation and down to earth. Too long (ie more than 10 feet), too many sharp bends, not separated from other non-grounding wires, etc.

Why does your CO not disconnect phone service during each storm? Why is that $multi-million computer not damaged? Because every incoming wire inside every cable connects low impedance to single point earth ground. And because protectors are distant from electronics. Increased separation between protector and electronics INCREASES protection. They want that separation up to 50 meters. You want something similar.

Defined were protectors that cost about $1 per protected appliance. But again, no protector does protection. Protectors are only connecting device to what harmlessly absorbs hundreds of thousands of joules. Protectors are simple science. 'Art' of protection is the only item that always exists in every protection system - single point earth ground.

You should have plenty of questions. Including more about the 'primary' protection layer. Above only discusses a 'secondary' layer.

 

[GotNoRice]

Seems to be lots of good advice there, thank you.

Your telco's $multi-million switching computer connects to all other buildings. Therefore it will suffer about 100 surges with each storm. So they disconnect phone service before each storm? Of course not.

Interesting example, though I've used VoIP for over 10 years now, and before that, can't recall ever using a phone during a storm.

You can install same for about $1 per protected appliance. But it means learning some concepts originally introduced in elementary school science (ie Ben Franklin's lightning rod).

That elementary school comment comes off as unnecessarily condescending; I'm not sure that really added anything to the conversation.

Most common source of damage is AC mains. A direct lightning strike far down the street is a direct strike incoming to every appliance. So all appliances are damaged? Of course not. Only damaged is an appliance that also has an outgoing path to earth ground. For example, a strike incoming to the TV on AC mains will be outgoing to earth via the coax or HDMI port. Damage is often on the outgoing path; not on an incoming path. Then naive consumers want to blame the coax.

Don't all 3-prong appliances automatically have an outgoing path to earth ground? I don't understand why a strike coming in over AC would travel through an appliance and then out an HDMI port rather than the ground offered by the AC socket itself.

Cable companies strongly discourage protectors on their cable for a long list of reasons. Including best protection is already installed for free. Your damage is directly traceable to AC mains that were not connected low impedance (ie less than 10 feet) to single point earth ground. A defect that exists today in almost every home doe to so many homeowners who never learned this stuff.

Most homeowners didn't build their own homes, so how would they be responsible for the defect? Or perhaps a more useful question would be, what is the easiest, most realistic way to test for this? And to be clear, you're talking about 10 feet from the breaker box, right?

Whole house protectors come from companies with better integrity including Square D, General Electric, Polyphaser (an industry benchmark), Ditek, Intermatic ABB, Syscom, Levition, and Siemens ... to name but a few. Cutler Hammer solutons are found in Lowes and Home Depot. Clearly not listed are Isobar, Monster, APC, Belkin, Tripplite or Panamax. Those protectors have no dedicated and low impedance connection to earth. Those protectors will not discuss where hundreds of thousands of joules harmlessly dissipate.

I'm not disagreeing with you, just curious; Is the ground found in every 3-prong outlet completely useless in this context? I simply assumed that was where these sorts of devices were sending the extra energy.

Useful answers also provide critically important numbers. For example, the ground wire from breaker box to earthing electrode has excessive impedance if it goes up over the foundation and down to earth. Too long (ie more than 10 feet), too many sharp bends, not separated from other non-grounding wires, etc.

What exactly is considered excessive impedance? Is this something that can be easily measured via multimeter or similar, or does it simply come down to measuring the length and path of the ground wire?

Why does your CO not disconnect phone service during each storm? Why is that $multi-million computer not damaged? Because every incoming wire inside every cable connects low impedance to single point earth ground. And because protectors are distant from electronics. Increased separation between protector and electronics INCREASES protection. They want that separation up to 50 meters. You want something similar.

This comes off as a bit vague in the context of a residential household. If we define protection as a low impedance connection to a single point earth ground, and that connection typically occurs at the breaker box, then are you saying that electronics should be 50 meters from the breaker box?

 

[michalrz]

A low impedance path to ground could be as low as 1 ohm (code reuires <4, right?), but we're talking millions of volts so that's still millions of amps rushing. Can't that appear in nearby (in house) circuits through induction?

I don't understand why a strike coming in over AC would travel through an appliance and then out an HDMI port rather than the ground offered by the AC socket itself.

I think it's simply because it can - there's still some impedance that leaves some of the current to travel around.

 

[westom]

Don't all 3-prong appliances automatically have an outgoing path to earth ground?

No. A number is one of many reasons why. Low impedance (ie 'less than 10 feet'). How many feet from appliance to that safety ground in a receptacle. That is safety ground; not earth ground. How many more feet inside walls? How many sharp bends? How many splices? Etc. All can result in low resistance and high impedance.

Elementary school science comment is only condescending if thinking emotionally like a child. A hard reality has no emotions. These concepts were originally introduced in elementary school science. A majority forget simple science to not learn this stuff - to also hope a plug-in protector is protection; that safety ground is earth ground. That is the point. To not know this means forgetting concepts taught in elementary school science. That is simply a reality that also explains why a majority have so little grasp of protection.

Impedance is why that maybe 0.1 ohm resistance connection from receptacle to breaker box can also be 120 ohms impedance. A trivial 100 amp surge using that 120 ohm path means something approaching 12,000 volts between receptacle and breaker box. Yes, that voltage number should have everyone's attention because wire length (not thickness) is should be addressed.

High voltage only exists when impedance is excessive. Protector connected low impedance to earth means a high current and a near zero voltage. A high current times a near zero voltage is near zero energy. That is why the 'whole house' solution is so effective - energy dissipates outside and elsewhere.

Those same numbers also say why it is best to have appliances separated from protectors. 50 meters would increase appliance protection assuming that connection does not introduce other complications (that might compromise protection).

Even 50 feet separation is why one properly earthed 'whole house' protector provides so much protection for everything. But let's be blunt. No protector does protection for the same reason no lightning rod does protection. In every case, protection is defined by what harmlessly absorbs hundreds of thousands of joules.

How many joules does a UPS or power strip claim to absorb? Another example of why numbers such as 50 meters, 'less than 10 feet', and the 'art' of protection (single point earth ground, equipotential) are only discussed with proven solutions; not with plug-in solutions.

Your protection is only as effective as earth ground. Only a homeowner is responsible for same reasons that a homeowner is responsible for what his contractors do.. A surprisingly large number of electricians do not know anything about surge protection. impedance, or what is required to have a single point earth ground. Many homeowners and electricians mistakenly assume that one AC (neutral) wire connected to earth (to meet code) is sufficient. It is not. Every wire (not just all three or more AC electric wires) must connect low impedance to earth. Either directly via a hardwire (a best connection) or by using a next best thing - a 'whole house' protector.

Only homeowners are responsible for this earthing. You might fight with the contractor for not doing it right. But the bottom line is a homeowner is ultimately responsible. Even a Telco, satellite dish, or cable TV protection is only as effective as the earth ground provided by the homeowner.

 

[GotNoRice]

No. A number is one of many reasons why. Low impedance (ie 'less than 10 feet'). How many feet from appliance to that safety ground in a receptacle. That is safety ground; not earth ground. How many more feet inside walls? How many sharp bends? How many splices? Etc. All can result in low resistance and high impedance.

You had previously said "Only damaged is an appliance that also has an outgoing path to earth ground. For example, a strike incoming to the TV on AC mains will be outgoing to earth via the coax or HDMI port.". I realize now that you were likely saying that in the context of having traditional cable boxes hooked up. We use Uverse where traditional coax connections are not used for most boxes, and nothing should be connected to anything that has a special connection to ground. I assumed that in that situation the "safety ground" on a traditional AC plug would still represent the lowest impedance path to ground, even if it is not as low impedance as an "earth ground". It wasn't my intention to imply anything else.

Elementary school science comment is only condescending if thinking emotionally like a child. A hard reality has no emotions.

While it's clear that you do have a wealth of knowledge about this subject, your people skills could certainly use a little work. This might come as a surprise to you, but there are many people on here that help others every day, and manage to do so without being derogatory and condescending. Perhaps this is a topic that you are passionate about, but consider this. I am on here asking questions and admitting ignorance about stuff that I do not know. Perhaps you should save your negative emotions for those who don't ask questions, and instead choose to be content with misinformation.

You didn't directly answer most of my questions that I had about your last post, but you did go on a multi-paragraph rant about a minor comment that I made regarding homeowner responsibility. Save it for the Soapbox.