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Re: Panel Grounding vs. Lightning Rod Grounding

> > 3) ... if there is a close by or direct lightning hit, then all of th= e > > electrical wiring, including the sensor wires for the alarm system, > > will now become antennas that will attract arcing or inductive surge > > loadings. > > Don't worry about fields from a nearby strike. Such 'damage' is > promoted by myths and speculation.

. Francois Martzloff was the NIST guru on surges and wrote the NIST guide along with many published technical papers.

Martzloff was involved in an investigation that included an insurance company and a power utility that took a very limited look at equipment damaged by surges. One of the cases was a multichannel audio amplifier that had several channels damaged by a very near lightning strike that was picked up on speaker wires.

From the NIST guide: =93Surges of a slightly different kind can also happen in parts of other electrical systems that do not directly involve a power line. Examples of these are: the antenna for a remote garage door opener, the sensor wiring for an intrusion alarm system.... Surges in these systems are caused by nearby lightning strikes.=94 And: =93Intruder alarm systems using wires between sensors and their central control unit can be disturbed - and damaged in severe cases - by lightning striking close to the house. The wires necessary for this type of installation extend to all points of the house and act as an antenna system that collects energy from the field generated by the lightning strike, and protection should be included in the design of the system, rather than added later by the owner=94

Direct pickup is very low concern compared to surges coming in on utility wires.

-- bud--

Reply to
bud--
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Bud forgets to mention how easy that problem is eliminated even by protection inside panels. That thousands of volts is easily diminished to near zero by a milliamp conductor - the neon glow lamp. Bud has hyped a fear and ignored the solution that already makes the problem irrelevant.

What field is far more destructive? If trying to earth a surge via a plug-in protectors, then the safety ground wire inside Romex induces surges on all adjacent wires. Fields from nearby strikes are easily made irrelevant. Fields created by an earthing wire not separated from all other wires can induce surges on those other wires. Only one of us actually learned this stuff from both IEEE papers and experience.

Meanwhile Martzloff describes in the very first conclusion of his IEEE paper how a plug-in (point of connection) protector can contribute to damage of adjacent electronics (as also demonstrated on Page 42 Figure 8):

Bud likes to forget the parts that show how obscenely profitable plug- in protectors can even contribute to electronics damage.

Reply to
w_tom

Why don't you guys get a room? Jeeeeze!!! This love affair needs to go somewhere else.

Bud forgets to mention how easy that problem is eliminated even by protection inside panels. That thousands of volts is easily diminished to near zero by a milliamp conductor - the neon glow lamp. Bud has hyped a fear and ignored the solution that already makes the problem irrelevant.

What field is far more destructive? If trying to earth a surge via a plug-in protectors, then the safety ground wire inside Romex induces surges on all adjacent wires. Fields from nearby strikes are easily made irrelevant. Fields created by an earthing wire not separated from all other wires can induce surges on those other wires. Only one of us actually learned this stuff from both IEEE papers and experience.

Meanwhile Martzloff describes in the very first conclusion of his IEEE paper how a plug-in (point of connection) protector can contribute to damage of adjacent electronics (as also demonstrated on Page 42 Figure 8):

Bud likes to forget the parts that show how obscenely profitable plug- in protectors can even contribute to electronics damage.

Reply to
Bob Worthy

Bob, I won't presume to speak for others in the group, but frankly I very much appreciate these guys taking their time to educate me, and I have learned a lot from them. And your contribution to the discourse has been ... ... (?)

Reply to
David

. I said direct pickup was low energy and terminals "*may* not be protected". Not all equipment is protected. I tried to cover the sources of surge damage. Martzloff says in the NIST guide (quoted above) direct pickup can be a problem. .

. w_ likes to forget that Martzloff said in the same technical paper "Mitigation of the threat can take many forms. One solution. illustrated in this paper, is the insertion of a properly designed [multiport plug-in surge suppressor]."

Martzloff says in the NIST guide plug-in suppressors are effective.

The IEEE guide says plug-in suppressors are effective.

Poor w_ doesn=92t think they work.

-- bud--

Reply to
bud--

Aside from the fact that proper earth grounding has now been "flogged" to a second death, the fact is that it doesn't matter whether your security panels grounded or not. Lightning remains unpredictable. If you're unlucky enough to have a strike anywhere near you, you could very well wind up with fried equipment regardless of what you do to "protect it". Most panel manufacturers suggest grounding to a cold water pipe. There's only one "right" way according to them, and a whole lot of "right" and "wrong" ways (according to those that have posted responses here). It has indeed proven "educational" (except for the flames which are just plain dumb).

Reply to
Frank Olson

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