LIGHTNING CLAIMS

Ah!, springtime. Mild temperatures. New foliage on the trees. Flowers and shrubs in bloom. Baseball season starting. Spring showers, - Lightning!! Yes, with everything else that spring brings, it also brings lightning claims. (Sometimes whether there has been lightning or not!)

The lightning bolts you see are channels of pulsing electric energy two inches across. They may be as short as 200 feet or as long as 20 miles. They travel through the air at 90,000 miles per second, nearly half the speed of light, and heat up the surrounding air to 50,000 degrees Fahrenheit, five times the temperature of the surface of the sun.


Although three-quarters of the bolt's energy is used up in heat, enough remains to deliver a full 125 million volts of electricity. With one hundred lightning bolts blasting the earth every second, lightning provides more energy than all the electric generators combined in the United States. It is also a major cause of power outages in this country as well, bursting transformers with its sudden surges of power.

It should come as no surprise to the readers of this newsletter that lightning accounts for hundreds of millions of dollars' worth of property damage every year. It also generates more property claim related business for FORCON than any other single type of occurrence, particularly in the southeast. That is why we have devoted this entire issue of Bridge-the-Gap to some of the various types of lightning related claims we get involved in, and what we've learned about them.

RESIDENTIAL SATELLITE RECEIVER SYSTEMS

In most rural areas of the country where there are no cable TV systems yet. It has become common for homeowners in outlying communities to have sophisticated satellite receiver systems. Unfortunately for the insurance companies that provide property coverage on these residences, satellite receiver systems are highly susceptible to lightning and lightning induced electrical surges.

A combination of factors makes these claims ones that the adjuster needs to be wary of

While most lightning damage claims on satellite receiver systems may be valid as to the cause of the damage because of the susceptibility of these systems, our experience to date indicates that the dollar amounts claimed are much higher than they should be. If you resolve these claims by accepting the service company's statement that the damage cannot be repaired economically, and without determining whether the proposed replacement components are equivalent to the ones they are replacing, you are probably paying much more than you need to.

The question then is - What can you do about it? Well first,it would probably help for you to know a little more about the technology you're dealing with and how lightning can effect it.

SYSTEM DESCRIPTION

A typical residential satellite receiver system is depicted in the block diagram below.



The most recognizable part of the system is the dish antenna which is located in the yard or on the roof of the house. Mounted on the dish antenna are signal processing electronics, and a drive system (actuator) to move the dish so that it can be pointed at the desired satellite. The signal processing electronics located in the feedhorn include a low noise block convertor (LNB), and the antenna polarity switch. The remaining four functional components (Receiver, Descrambler, Power Supply, and Satellite Locator) are normally located in the house in close proximity to, if not on top of, the T.V. set.

Here's how it all works! Satellites receive signals from the various T.V. station transmitters and retransmit the signals back down to earth over a wide area. The satellite receiver dish gathers these signals along with whatever other energy it intercepts. This energy is then reflected and focused by the dish into the feedhorn waveguide aperture. A small antenna in the waveguide captures this energy. The polarity switch aligns the antenna so that the signals can be kept separated from one another.

The antenna in the waveguide is connected to the LNB which provides low noise amplification of the signal and conversion of the transmitted frequency to a level that allows the use of low cost coaxial cable to carry the signal to the in-house receiver without serious signal loss. In some older units there is a separate low noise amplifier (LNA) followed by a downconverter instead of a single LNB.

The function of the receiver is to select the desired T.V. channel from all those presented to it by the LNB and then perform other functions in order to extract the video and audio signal that a T.V. can accept. The receiver is a complex device performing numerous functions. It is normally micro-processor based.

Since the companies that operate the satellite T.V. networks want to make a profit they do not want everybody to be able to monitor their broadcasts without paying and therefore the industry has adopted a standard for scrambling their signals for which the consumer must pay a royalty to have the capability of viewing any or all of the T.V. channels broadcast. When you pay your royalty your descrambler, which is a physical entity and which you must purchase, will be provided with the programming to descrambler that set of T.V. channels you subscribed for. A descrambler is not required in a satellite receiver system. Just as in a cable T.V. system there is a sub-set of channels that are not scrambled and are broadcast in the clear that anyone can monitor.

Most systems sold today have the capability that the subscriber can select which satellite is to be monitored and the system will point the dish at that satellite. For this to occur the dish antenna must be fitted with an actuator, normally a DC motor driving a screw driven arm, and dish position sensors, normally magnetic reed switches today but some existing older units used potentiometers. With the dish antenna so equipped the functional block called satellite locator, when told which satellite, will drive the dish till the position feedback indicates that the dish is pointing at the selected satellite.

The remaining functional component of the block diagram found in the residence is the power supply. It is rare to see this component as a single standalone unit as it is normally incorporated into each of the electronic units that comprise a given satellite receiver system. Its function is to connect to the residential source of 115 VAC power and convert it to the differing levels of DC voltage required by the unit(s) it serves.

The four major functional components that normally reside in the residence, the receiver, power supply, satellite locator and descrambler today are packaged in one unit which is referred to as an IRD, Integrated Receiver Descrambler. The function of the satellite locator is then programmed into the receiver micro-processor and is no longer a physically separate entity. It is still common today to find the receiver, descrambler and satellite locator each housed in their own chassis with power supply. These are units of vintage mid-late 1980's. In all units regardless of how the functional components are grouped for packaging, the descrambler is a separate PC board which is removable and may be taken directly from one manufacturers unit and put into that from a different manufacturer. This is so because all the descramblers are built by one manufacturer, General Instrument, who has the copyright on the scrambling and descrambling algorithms adopted by the satellite T.V. industry today.

LIGHTNING SUSCEPTIBILITY

As we mentioned earlier, satellite receiver systems are highly susceptible to lightning damage. The amount of damage caused by the lightning strike will depend upon the proximity of the strike. A direct hit by lightning is not the norm, and indeed if it did occur one would look for the smoking crater and replace the entire system. Electrical damage occurs when lightning strikes nearby tall objects such as trees and power transmission towers. These are the type of lightning strikes that we are most often dealing with.

When lightning strikes it creates electric fields in the air which can induce voltages into electrical system wiring such as the utility power system. Power line surges can be created if the utility takes a direct hit on a transmission tower or even induced into the local distribution system wiring by a proximity strike. A power line surge will be the result with only its intensity unknown. This is probably the more common cause of satellite receiver system damage and will normally effect other electrical appliances in the residence at the same time. The power line surge can do more damage if the receiver system is in use at the time of the incident since then the power supply regulating circuitry can be overwhelmed causing abnormally high DC voltages to be produced which can then damage the units the power supply serves as well as the power supply itself. Knowing that the system was not in use at the time of the strike does not mean that no damage is expected, only that the damage may be localized within the power supply.

If the electrical utility power system is not effected, the satellite receiver system could still be damaged by the electrical field inducing voltages into the dish antenna. This could effect the in-home components by coming into the house via the cables normally buried in the ground. If the lightning strike were to cause large ground currents to flow, these could induce voltages directly into the buried cable with the same damaging effects. In this situation one would most likely lose the LNB on the feedhorn, maybe even the coax cable to the receiver, the IF section of the receiver and possibly the circuitry in the receiver driving the polarity switch. If it was a strong hit, the damage to the receiver could be more extensive but normally the power supply would survive.

CLAIM CONSIDERATIONS

When a claim is made for loss of all or part of a satellite receiver system 90% of the time the insured's serviceman will state that the equipment is unrepairable and needs to be replaced with new. The claims adjuster has to then make three main determinations (1) was lightning the cause of loss, (2) can the equipment be repaired, and (3) if it is to be replaced, is the proposed equipment the most comparable to that lost.

Determining the cause of the loss, especially where there are no visible signs of lightning damage, takes a thorough understanding of the receiver system operation to determine rationality between the extent of damage and probability that it could have been caused by lightning. Often to determine the extent of damage requires further testing. Most servicemen will recommend replacement simply because their companies are not capable of performing repairs to the system PC boards. If they farm the work out to another shop their profit margins will be much smaller than if they replaced the equipment with new. Most lightning damaged equipment can be repaired. Repair may or may not be the most economical or practical solution and again experience with damaged systems and the capability to test the equipment to the extent that a rational determination of the probability of success of the repair is crucial. If the determination of replacement is substantiated then the damaged equipment must be reviewed against what is currently offered for sale to ensure the replacement equipment does not warrant an unnecessary upgrade.

As you might expect, FORCON can help you make these determinations. Call us if you need help with any of these claims.

Stan Lamberski - FORCON Consultant