[Top] [All Lists]

Re: [TowerTalk] LRC - Lightning Retardant Cable

Subject: Re: [TowerTalk] LRC - Lightning Retardant Cable
From: K8RI <>
Date: Sun, 03 Jun 2012 23:17:49 -0400
List-post: <">>
On 6/3/2012 10:17 PM, Martin Sole wrote:
> I hadn't heard of this before and at first was rather sceptical, still am to
> some degree, but it appears to be real enough and might in some types of
> installation be effective. Here are a few links to information:

Based on my, and most every one else's feeble understanding of 
lightning:  Near as I can tell
They use a 3 layer/conductor consisting of a central conductor, and two 
*wound* outer layers at *roughly* 90 degrees to each other which would 
put them at 45 degrees to the center conductor and separated by a high 
voltage insulation that has a high dielectric constant that is also high 
temperature and fire resistant.

Theoretically, and I have to emphasize the "theoretically" it should be 
capable of reducing, induced voltage spikes, BUT I'd have to see test 
data to have much faith in anything beyond low to medium voltage induced 
spikes.  It would "likely" add another layer of protection for voltage 
sensitive devices, but with the variability and unpredictability of 
lightning you are always playing the odds where a nearby strike may be 
suppressed via simple means to a direct hit from a super strike that 
only divine intervention or luck can protect what ever.

A straight conductor has very little inductance, but even a large tower 
can posses enough that a strike with a rapid rise time will cause the 
current to build so fast that it becomes self quenching and the stroke 
will jump off the tower sideways.

If I read the description correctly this conductor appears, or is 
claimed to appear as two chokes on the cable that will cancel the 
current from the lightning strike, making the cable appear to be much 
longer than its actual dimensions.

Having seen a shorted 1 1/2" diameter, solid copper buss whip around 
like a snake while the arc burned the ends back like a fairly fast 
burning fuse, I have my doubts as the effectiveness at handling much 
power. OTOH *most* induced spikes do not contain a lot of power and they 
are of short duration.  That, combined with not having seen any test 
data leaves me having to reserve an informed judgement about the 
performance under specific conditions.

BUT we recently had a rather long discussion on here about diminishing 

So, until I could actually see the test figures and conditions I think 
I'd stick with the more conventional methods of grounding and bypassing 
for equipment protection that have proven effective for what they were 
designed while keeping in mind that there is nothing that will give us 
100% protection.  A really big strike very close can induce enough 
voltage into the unplugged power cord to do damage, but those are 
extremely rare and you won't be concerned about the equipment until the 
ringing in your ears is reduced to the point where you can again 
understand speech and the tingling in your extremities is mostly gone.  
Nerves are something else<:-))


Roger (K8RI)

> I also have the US Navy test report from 2004 on lrc RG-214 that states
> improvements in phase stability and local interference pickup.
> I am interested to know if any here have looked at this product or can
> indicate what value it might add to an installation. My own initial feeling,
> after I had suspended my instant disbelief, is that in most amateur
> installations it probably adds little real benefit in terms of lightning
> protection where much of the intrinsic protection comes from other elements
> in the antenna system or indeed the whole outdoor network of objects.
> Martin, HS0ZED
> _______________________________________________
> _______________________________________________
> TowerTalk mailing list


TowerTalk mailing list

<Prev in Thread] Current Thread [Next in Thread>