Surge Protectors
in [Repair]
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From: William Sommerwerck on 19 Jun 2010 09:26 > It is bud's job to constantly promote lies and myths. He is paid > to promote plug-in protectors. Lying is what promoters may do. > Where are those numeric specs? bud will never provide any. > He cannot claim protection that does not exist. > Where does that energy dissipate? bud cannot say. Otherwise > he must admit that plug-in protectors are profit centers � not > protection. Uh... In the MOV? I thought the MOV conducted above its breakdown voltage (generally around 300V), and the energy in the section of the AC waveform above that voltage heated up the MOV. Am I missing something? Many years ago, PC and/or Byte (I forget which) used to test suppressors. If they failed to provide suppression, I assume the mag would have said so.
From: Jim Yanik on 19 Jun 2010 12:18 "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote in news:hvigjf$hg7$1(a)news.eternal-september.org: >> It is bud's job to constantly promote lies and myths. He is paid >> to promote plug-in protectors. Lying is what promoters may do. >> Where are those numeric specs? bud will never provide any. >> He cannot claim protection that does not exist. > >> Where does that energy dissipate? bud cannot say. Otherwise >> he must admit that plug-in protectors are profit centers � not >> protection. > > Uh... In the MOV? > > I thought the MOV conducted above its breakdown voltage (generally > around 300V), and the energy in the section of the AC waveform above > that voltage heated up the MOV. > > Am I missing something? Ohm's Law. If the MOV conducts at a low resistance,the power it dissipates will be minimal. Thus,the surge energy gets dissipated in whatever ground it's shunted to. -- Jim Yanik jyanik at localnet dot com
From: Jeffrey D Angus on 19 Jun 2010 12:25 William Sommerwerck wrote: > Uh... In the MOV? > > I thought the MOV conducted above its breakdown voltage (generally around > 300V), and the energy in the section of the AC waveform above that voltage > heated up the MOV. > > Am I missing something? In your typical plug in suppressor mounted next to the computer for example. The job of the MOV is to clamp the maximum voltage across the "protected" outlets. That it does this fairly quickly is what hopefully protect the equipment, while at the same time drawing enough current through the house wiring to either pop the fuse or circuit breaker at the suppressor or back at the service panel. What the plug-in suppressors rely on is the impedance (generally inductive) in the house wiring to limit the rise time of the surge until the circuit breaker (or fusable parts) have time to react by opening up. The term joules can be described as Watt Seconds. And the ability to deal with it is based on the fault (or surge) being over, or the circuit breakers upstream open before the device self destructs. Whole house protectors work the same way in that they shunt the current to ground safely before it has a chance to cause a destructive rise to the rest of the house wiring. Jeff -- �Egotism is the anesthetic that dulls the pain of stupidity.� Frank Leahy, Head coach, Notre Dame 1941-1954 http://www.stay-connect.com
From: William Sommerwerck on 19 Jun 2010 12:27 >> I thought the MOV conducted above its breakdown voltage (generally >> around 300V), and the energy in the section of the AC waveform above >> that voltage heated up the MOV. >> Am I missing something? > Ohm's Law: > If the MOV conducts at a low resistance, the power it dissipates will be > minimal. Thus, the surge energy gets dissipated in whatever ground it's > shunted to. How low is low? I suspect that's not a complete explanation, but I won't argue at this time.
From: Cydrome Leader on 19 Jun 2010 18:41
William Sommerwerck <grizzledgeezer(a)comcast.net> wrote: >> It is bud's job to constantly promote lies and myths. He is paid >> to promote plug-in protectors. Lying is what promoters may do. >> Where are those numeric specs? bud will never provide any. >> He cannot claim protection that does not exist. > >> Where does that energy dissipate? bud cannot say. Otherwise >> he must admit that plug-in protectors are profit centers ? not >> protection. > > Uh... In the MOV? > > I thought the MOV conducted above its breakdown voltage (generally around > 300V), and the energy in the section of the AC waveform above that voltage > heated up the MOV. > > Am I missing something? > > Many years ago, PC and/or Byte (I forget which) used to test suppressors. If > they failed to provide suppression, I assume the mag would have said so. hillarious, PC magazine is your source for the lowdown on surge supression devices? |