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I live in an older (1970s) home that unfortunately does not have a grounded electrical panel and none of the outlets have ground wires. Last year when there was a lightning strike, I lost my NAS and a couple of other devices. I don't have the money to pay an electrician to rewire my entire home at the moment, so I'm trying to come up with solutions short of that. I've already changed out about 50% of the outlets to GFCI to prevent shocks etc., but it's my understanding that a GFCI won't do anything to prevent a device from being fried during a lightning strike.

If I had a whole-home surge protector installed at the panel, added a ground bar to the panel, and then ran a ground rod to the outside, would this protect all my appliances/devices in the home from a lightning strike?

Essentially, I'm trying to protect my devices from being fried without rewiring the entire home so that every outlet has a ground wire. I appreciate any help!

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    It should help to a point. Usually the best protection for devices from lighting strikes is to unplug. Surprised that a 70s house(North American) is ungrounded, maybe a 50s house.
    – crip659
    Commented Feb 3 at 19:32
  • Yeah, it's very disappointing and perplexing they chose to skimp on that. I'm not sure what the cost was in ~1975, but it seems trivial in the scheme of things to buy 14/2 or 12/2 with a ground versus without a ground. But, I've found a lot of things around the house that you can tell he was just kind of a cheap ass. As for the lightning strikes, I just hate to have to unplug my computers and all electronics every time it is raining or could have a possibility of lightning strikes. From reading a little bit further, it seems like maybe a Type 1 vs Type 2 SPD may be better? Commented Feb 3 at 19:51

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To start with, you really ought to install a proper Grounding Electrode System, providing grounding at the panel. That is the foundation of any grounding system, and it usually happens in unfinished utility spaces like your basement. So it's not prohibitive.

You seem fixated on the idea of replacing all the wires in your home. That's fine if cost is no object, but most people handle this situation other ways.

First, as you have done, GFCI protection can be provided. Like most people, you seem to think GFCI protection is a receptacle, and it must be installed at every receptacle. Not necessarily so -- GFCIs have a special set of terminals which allow a GFCI to protect the entire circuit downline of that point. These special terminals should be used ONLY for that purpose, and are called "Load". As such, you need as few as one GFCI receptacle per circuit, in the first outlet past the breaker. That means GFCI protection can be rolled out economically.

The downline outlets are then marked "GFCI Protected - No Equipment Ground" as Code requires at 406.4(D). Without the labeling, it is a code violation. Ugly blue labels are provided for your convenience, but the labeling can be done in any manner that is not hand-written.

The other method is to retrofit just a ground wire, per NEC 250.130(C). You don't need to follow the same route as the conductors, nor do you need to go back to the panel - just any junction box with the correct or larger ground wire going back to the panel. So you can spiderweb ground retrofits in a different topology than the wires.

Nothing will protect from a lightning strike, but many surge suppressors install inside the electrical panel. They do not need a dedicated circuit, they can piggyback/share a breaker with a large load. The relevant thing is that many come with equipment insurance / a warranty that covers destroyed equipment.

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A surge protector will probably help with typical surges, if you have a decent modern two-rod ground put in.

Surge protectors only help with small transients. They will not help when a car runs into your power pole and the 13kV distribution line falls on your 240V feed.

With lightning, all bets are off. Lightning-level power overcomes normal insulation characteristics, and electricity will go where no electricity has gone before. No amount of grounding and surge protection can be relied on to protect from a lightning strike on or near your house.

You may be able to deflect the lightning to a safe dump point by installing a lightning rod system with its own grounding system.

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  • I believe the last lightning strike (which fried my NAS and a couple of cables etc) struck a couple of houses down from me, rather than directly striking my house. I assume it traveled along the distribution lines and into my house (and presumably other houses -- I believe my next door neighbor had her TV get fried too.) It sounds like there is not a lot I can do to prevent this type of scenario. Commented Feb 3 at 20:48
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    It could just be possible that a really high-quality whole house surge protector might just have helped your house in that situation. But probably not the house a couple properties down. And not yours if the strike point were your house instead. Commented Feb 3 at 21:11

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