Surge / Ground / Lightning
in [Home Built PC]
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From: "nobody >" on 4 May 2008 15:34 phil-news-nospam(a)ipal.net wrote: > In alt.engineering.electrical Timothy Daniels <SpamBucket(a)nospamplease.biz> wrote: > > | Would you please sum up what you believe to be prudent > | protection (for electronic equipment) from nearby lightning strikes? > | I'm thinking of both in single-family homes and in condo/apartment > | buildings. What would you do to protect from in-house (or in-building) > | surges, such as elevator motors suddenly shorting out, or welding > | equipment in use? > > How much money are you willing to spend? > The only thing I can think of that comes close is to have a heavy motor/generator set with a HUGE flywheel sitting in the basement.
From: phil-news-nospam on 5 May 2008 01:44 In alt.tv.tech.hdtv bud-- <remove.budnews(a)isp.com> wrote: | phil-news-nospam(a)ipal.net wrote: |> In alt.engineering.electrical Leonard Caillouet <nospam(a)noway.com> wrote: |> | <phil-news-nospam(a)ipal.net> wrote in message |> | news:fvjhvk016vr(a)news5.newsguy.com... |> |> In alt.tv.tech.hdtv Franc Zabkar <fzabkar(a)iinternode.on.net> wrote: |> | |> |> |> |> The MOVs will act like conductors when they are clamping. The surge will |> |> take both paths ... the path through the MOVs, and the path going past the |> |> MOVs. In general, about 50% will go each way. That can vary at higher |> |> frequencies. |> | |> | Why would you assume that 50% will go each way when you don't know the |> | impedance of each direction? When conducting, or at failure, the MOV has a |> | very low impedance. |> |> There is a distinction between "go each way" and "what comes back" due to |> the impedance. It will be about 50% that goes each way _because_ the power |> itself does not (yet) know the impedance (at a distance), until it gets |> there. | | Another installment of Phil's Phantasy Physics using transmission line | theory. Not understanding it is your loss. | Two sources directly contradict Phil. What sources? Your truncated out of context quotes? | Phil has provided no sources to support phantasy physics. I don't care. -- |WARNING: Due to extreme spam, I no longer see any articles originating from | | Google Groups. If you want your postings to be seen by more readers | | you will need to find a different place to post on Usenet. | | Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) |
From: w_tom on 6 May 2008 21:46 On May 6, 12:08 pm, "Michael A. Terrell" <mike.terr...(a)earthlink.net> wrote: > Where did I say HOW was protected? It was my second week at that > station, and the chief engineer took off on a long overdue vacation. If > you would learn to read, rather than just do mindless rants you wouldn't > look so stupid. At that time the building had a UFER ground, and a > three phase protection system at the meter CTs. That didn't prevent the > damage, as you claim it should. Lightning created damage. Since Michael Terrell says it had an Ufer ground, that means grounding was properly installed and not corrupted? Therefore the resulting damage proves, "Woe is me. Nothing can protect from lightning."? Nonsense. Damage was created by a surge. A responsible human locates the defect in that protection system. Michael Terrell was defeatist. He 'knew' nothing can earthing lightning without damage. Then Michael posts nonsense about other protectors so he need not admit this fact: MOVs are not used on telephone lines. Why discuss fuses? Fuses obviously are not for surge protection - when one has basic electrical knowledge. Effective protectors (even gas discharge tubes - GDTs) earth direct lightning strikes and remain functional. So why is Michael now discussing GDTs and fuses? Michael has again been caught posting in error. MOVs are not used for telephone line surge protection due to excessive capacitance. This has long been common knowledge among those who post facts - not insults. Nnoted and finally admitted by Michael is a reasons why so little lightning in the UK creates so much damage. Master sockets are not even earthed as the equivlant NID is, routinely, in all North America. Responsible people who suffer surge damage immediately search for the human failure that made damage possible. Search typically begins by looking for defects in the single point earth ground system. Those who promote magic box plug-in protectors would not do this and must assume lightning damage cannot be avoided - a defeatist attitude.
From: Leonard Caillouet on 4 May 2008 17:55 <phil-news-nospam(a)ipal.net> wrote in message news:fvjhvk016vr(a)news5.newsguy.com... > In alt.tv.tech.hdtv Franc Zabkar <fzabkar(a)iinternode.on.net> wrote: > > The MOVs will act like conductors when they are clamping. The surge will > take both paths ... the path through the MOVs, and the path going past the > MOVs. In general, about 50% will go each way. That can vary at higher > frequencies. Why would you assume that 50% will go each way when you don't know the impedance of each direction? When conducting, or at failure, the MOV has a very low impedance. Leonard
From: VWWall on 4 May 2008 18:37
phil-news-nospam(a)ipal.net wrote: > In alt.tv.tech.hdtv Tony Hwang <dragon40(a)shaw.ca> wrote: > | Michael A. Terrell wrote: > |> Tony Hwang wrote: > |> > |>>Hi, > |>>Is he a ham? What is his call sign? > |>>Mine is VE6CGX. > |> > |> > |> > |> It's in his sig file: KA9WGN > |> > |> > | Hmmm, > | That is sign format of novice class. > > Which means my first ticket was novice. I upgraded a month after that. Don't forget to renew it before June 16. From FCC: KA9WGN Radio Service HA - Amateur Status Active Auth Type Regular Dates Grant 06/16/1998 Expiration 06/16/2008 Effective 11/13/2003 <snip personal info> -- Virg Wall |