On Jul 22, 2:03 pm, Doug Brown <[email protected]> wrote: > Clearly one of the issues is the age of the house and utilities not > bringing their ground systems up to spec. The house was built in 1960 > and has 2 prong wiring; that responsibility is on me but unless I win > the lottery I can't afford to rewire the house right now.
Safety ground is irrelevant to earth ground. Wiring from 2000 or 1930 can permit the same damage IF 'earth ground' is not properly installed. Both of Bud's citations make that point. For example, Figure 8 on page 47 of: http://www.google.com/url?sa=D&q=http://www.mikeholt.com/files/PDF/&usg=AFQjCNG5OJq2ORRcXRpJ_XI4a0wvLpB_Rg A plug-in protector has no earth ground. So it earths energy destructively via an adjacent TV. 8000 volts destructively. Every responsible source says this. Either energy dissipates harmlessly outside the building. Or that energy is inside (ie at a plug-in protector) hunting for earth destructively via appliances. 8000 volts destructively through an adjacent TV because energy was not earthed where wires enter the building. A protector was too far from earth ground and too close to electronics. Bud's NIST citation says the same thing: > A very important point to keep in mind is that your surge protector will work > by diverting the surge > to ground. The best surge protection in the world can be useless if > grounding is not done > properly. Either a protector connects short (ie 'less than 10 feet') to single point earth ground. Or "the best surge protection ins the world can be useless". Plug-in protector numeric specs confirm this. No plug- in protector numeric spec claims protection. It is a profit center - not surge protection. If it discussed earth ground, then you would learn how "useless" it really is. "Useless" is not my description. "Useless" is what the NIST says.. Bud's job is to promote plug-in protectors. So he will say anything to avoid critical facts that even the ARRL is blunt about. Protection is always about where energy dissipates. Not wall recoupable safety ground. Earth ground. Bud claims that energy just magically disappears. Professionals say that energy must be connected short (low impedance) to single point earth ground. As demonstrated by another professional's application note: http://www.erico.com/public/library/fep/technotes/tncr002.pdf Even underground wires must connect to single point ground before entering the building. Connect to earth via a wire (cable TV, satellite dish). Or connected to earth via a 'whole house' protector (telephone, AC electric). A connection that must be short. And other critically important factors such as no sharp wire bends and not inside metallic conduit. Plug-in protectors, without that always required earthing connection, make no protection claims in numeric specs. All phones have a 'whole house' protector typically where their wires meet yours (ie NID). But again, that protector is only as effective as the earth ground that only a homeowner is responsible for providing. One utility demonstrates how to kludge a solution if existing utilities do not properly enter at the service entrance: http://www.duke-energy.com/indiana-business/products/power-quality/tech-tip-08.asp ARRL makes the same point found in Polyphaser application notes and Sun Microsystems Planning Guides. Solutions required in Air Forces bases, telco switching centers, munitions dumps, commercial broadcasting center, etc. In every case, the solution to averting surge damage is to install or upgrade the earthing - where energy dissipates. Orange County FL 911 emergency response centers had surge damage. No plug-in protectors were installed. They simply fixed the only reasons for surge damage - defective earthing: http://www.psihq.com/AllCopper.htm A broadcast station installed Ufer grounding so that direct lightning strikes would not cause damage: http://scott-inc.com/html/ufer.htm A Nebraska radio station suffered repeat damage until someone finally fixed the only reason for that damage: defective earthing. A case study at: http://www.copper.org/applications/electrical/pq/casestudy/nebraska.html . Any wire that enters the building must connect short (directly or via a protector) to single point earth ground. The solution from over 100 years ago is still the only useful solution today. No plug-in protector does that. No plug-in protector claims effective protection the only place they cannot lie - numeric specs. In every case, protection means upgrading earth so that protectors make a short ('less than 10 foot') low impedance connection to that single point ground. Safety ground (what code calls equipment ground) is completely irrelevant to effective surge protection. No interior wiring is upgraded. The protection is just as good on 1930 homes as on 2010 homes. The other ground - earth ground - is required for effective protection. A protector is only as effective as its earth ground. -- You received this message because you are subscribed to the Google Groups "The Unique Geek" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/theuniquegeek?hl=en.
