Are lightning strikes dangerous to appliances if supply lines are buried in ground???
Frank: You are at risk. The reason why is called “ground rise potential”, sometimes called surge voltage. When the lightning strikes nearby there can be a substantial potential (voltage) difference between wire conductors even if they are normally at ground. The potential difference can be direct or induced (coupled) and it can be sufficient to damage your equipment . For instance a nearby lightning strike can induce a surge voltage into your house wiring that wants to find its way to ground any way it can. The copper water pipe burried in your yard could momentarily be a better ground than the power system ground so there could be a substantial surge potential difference between them and that copper water pipe near your computer could be the path to ground the surge voltage decides to take. You get the idea. Protectors which have MOVs that operate quickly can “short” this potential difference before it rises to a dangerous level for your equipment. An investment in protectors is worth
