A knot is a lot cheaper and does work .To me lighting is like red wires.
lenny

quote:

Originally posted by Tonka:
our cat’s absolutely terrified of electrical storms but for some reason still carries her tail pointed proudly straight up like a little furry lightning rod. I wonder if a figure eight knot would reduce her risk.

Wally

Don't do it.

Her tail is indeed a lightning rod..... However, the purpose of a lightning rod is not to attract lightning, but to aid in the equalization of static charges between the earth and the sky.

Lightning is Mother Nature's way of this charge being equalized, albeit violently. If the charges are equalized gradually, a little at a time, a lightning strike is less lightly.

So, your cat's tail is helping prevent a lightning strike.

Our airliners had what were called static wicks on extremities, such as wingtips, tail surface tips, etc. These were, in effect, miniature lightning rods. Some of them even had needle sharp tips, just like lightning rods. Points aid in the discharge (equalization) of electrical energy.

This not only diminished lightning strikes, but reduced radio static, particularly on older vacuum tube equipment. Even our gear doors and control surfaces had flexible wires connecting them to the structure. This allowed the smooth passage of static charges without them going through the hinge pins and bearings. This cut down on the pitting of those parts caused by the arcing that is inevitable with a less than perfect connection.

We still had lightning strikes, though. Lightning is just too powerful to control completely.

An issue often overlooked is that of buried wire. Underground cable is subject to "induced current". Current is induced when a conductor is subject to a changing magnetic field. Conversely, a changing current (like a lightning strike) creates a rising, then collapsing, magnetic field. That induces current in nearby underground conductors (like metallic water pipes and conduit, as well as power cables).

This phenomenon first got attention due to issues at the [then] new Tampa International Airport terminal. One of the officers (a CWO4) in my repair unit was superintendent of electrical services at TIA. He reported that the "people movers" that shuttled passengers from the main terminal to the airsides were suffering burned out supply cables, but the breakers (400A, 440V 3ph) weren't tripping.

Induced current was determined to be the culprit. The solution (at great expense) was to install what amounted to huge GFCIs further upstream.

quote:

Originally posted by Rusty:
An issue often overlooked is that of buried wire. Underground cable is subject to "induced current". Current is induced when a conductor is subject to a changing magnetic field. Conversely, a changing current (like a lightning strike) creates a rising, then collapsing, magnetic field. That induces current in nearby underground conductors (like metallic water pipes and conduit, as well as power cables).

This phenomenon first got attention due to issues at the [then] new Tampa International Airport terminal. One of the officers (a CWO4) in my repair unit was superintendent of electrical services at TIA. He reported that the "people movers" that shuttled passengers from the main terminal to the airsides were suffering burned out supply cables, but the breakers (400A, 440V 3ph) weren't tripping.

Yeah, the rise time of a lightning strike is way too fast for the breakers. Collapse time is probably even faster.

quote:

Induced current was determined to be the culprit. The solution (at great expense) was to install what amounted to huge GFCIs further upstream.

Were these buried or overhead? If buried, were the conduits metal or plastic? Is plastic conduit used in Florida?

My power lead-in cables from the pole transformer are going to be twisted and in metal conduit. I don't know about lightning, but twisting wires power or signal) always cuts the effect of stray EMF.

TIA has some 27 miles of burried cable. Cables are buried in dedicated concrete runs (tunnels).

DO not Forget that the surge protector.also tells of LOW voltage HIGH voltage. it is not a lighting arrester.IT helps save your equipment in the motor home .
The one we have takes two minuets to turn on if you have a bad line or a brownout won,t work or tells you not to use that line. I thought that someone had a problem AT cherry hill in that case it might have helped .IT might have helped me when we had a strike I THINK IT DID dealer said it was burnt for a reason
lenny