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Is this right way to use Lightning Rod?

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Willen

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Dish and rod has almost same height. How lightning acts in such conditions?
 

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As a Thumb Rule, A good lightning rod gives a 60° downward vertical coverage.
Thus, the Sat Dish is not protected.

Ramesh
 
I dont want to be a party pooper but it looks in the pic as though lightening would prefer your house than the dish.

The input to the sattellite receiver should be isolated, if not you can use an isolation transformer to reduce the risk of being struck in the first place.

Nigel will know more about this than me.
 
An isolation transformer by itself will not provide a lot of protection against the high voltage of a lightning strike. You should also connect the dish body to a new ground rod (separate from the lightning rod) and add a coax cable ground block, also connecting that to the ground rod.
 
I agree I dont think an isolation transformer would provide any protection from the onslaught of a strike, isolating the input from the receiver means the connections to the dish are floating with respect to ground therefore less likely to attract lightning by providing a potential.
Not sure about sky stuff but most old tv's have isolation on the rf input.
 
The purpose of a lightning rod (with spikes) is to discharge electrostatic charge buildup by dissipation and prevent a strike at the critical location. The rod is also kept as high as possible to "attract" a strike.

In spite of all the protection, if a strike does take place on the dish, it's good bye to the electronics.

Ramesh
 
The purpose of a lightning rod (with spikes) is to discharge electrostatic charge buildup by dissipation and prevent a strike at the critical location.

This is a popular misconception (Old Wives Tale)!

The purpose of a lightning protection system is to provide a low-impedance conductive path around the object being protected. It works by shunting the 40 to 100kA peak current pulse around the object being protected through a metallic wire, thereby keeping the peak voltage developed between the tip of the rod and the earth below to a few thousand Volts (by effectively shorting the local field with a conductor), and providing a controlled low-impedance path for the current pulse instead of letting it flow though the object being protected.

The Lightning rod is just the top few cm of the entire system. The rest consists of a large diameter (usually Copper) down-wire connected between the rod and an earthing system consisting of several ground rods driven up to meters into the earth below the rod.

Best Practice is provide a straight path (no bends, or as few as necessary) in the downwire. The grounding system where the destructive current pulse is to flow into the earth is all important. It must penetrate deeper into the earth than the building being protected (look up Ufer ground). It must have a net lower impedance to the earth than the grounding rods used by the power, phone, or cable company...

The rod is also kept as high as possible to "attract" a strike.

??? A structure that is "protected" is no more likely to get struck than the original unprotected structure would have been.
 
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