earthing the lnb possible?

[Turok]

Hello!
currencly,i plan,within the next 2 weeks,to earth all my big dishes on the roof,now i ask my self,could it be also posoble,that the lighting hits direct into the lnb,and destroy,all multiswiches,and receivers,or is this nearly inposible?
if not,how i can protect the lnb,from the lighting?
same way then the antenna itself?
problem here,the insurance,only accept the earthing,when it was installed,and certifed by a earthing protection electric company!

in the electronic stores,the sell also some lighting protectors for the lnb cable ,but i think,when the lighting hits there are also useless,and there protection not enough!

 

[dcselec]

Hi
I could be wrong but as lighting is looking for
the easiest way to earth ( lowest resistance )
if you earth all your dishes are you not attracting
the lighting by giving an easy path to earth would you
not be best just to unplug the sat box
Dave

 

[BombedOne]

Instead of earthing the dishes, better install lightning rod nearby. Or lightning fence.

 

[trigger]

Yes as per bombed one - fit a lightning rod.

I checked here as had an installation by a gas tank on the roof which already had a lightning rod and they said not to worry as the rod will do its job.

 

[Turok]

Hi there!
i want to earth my exiting 4 meter mast on the roof!
the 2 mast of the other antenna ,must be connected together,then i need a special connection cable,if i understand right,that transport the high voltage ,in the lightning rod,installed on the ground!

every house should have a main earth lighting connector,but currencly i dont know where it is!

is there some other material,that does not transport the power ,so good,then a normal iron mast?
maybe i massiv hard plastic mast,did not transport the power ,and when the lighting will hit,nothing would happen,problem,here is not allowed,to do the install by your self,only electronice engeneers can do it,because of the insurance,in every country it is diffrent!

can also something happen,when the receiver is off,and the lighting comes over the cable?#often i read,that only a complete replug helps,because the lighting is so strong,that it "jumps"over the small connection distance,in the on/off swtich,also lighting cord protectors,where i can put many electronic decive,does not help,when the voltage is to strong..!

what diameter the lighting rood should have and lenth?
how deep must it into the ground?
and does it realy work,to protect more mast together,at the same time,when there are all connected each other?

is earthing in uk also so expensice 1000 up to 1500€ here!
thanks for your input !

 

[satelliteman]

Might be of some interest
_http://www.furse.com/elp/elp.htm

 

[doktorofsat]

what diameter the lighting rood should have and lenth?
how deep must it into the ground?
and does it realy work,to protect more mast together,at the same time,when there are all connected each other?

the lightning rod must have at least 10-12mm diam

in the edge weld some cooper or silver

1m at least in the ground

 

[dcselec]

Can you post a pic of the mast if its insulated
from the earth eg on the roof it should be ok there
is no easy calculation on rods as it depends on the
soil its going into but if your dish is hit by lighting
it will be no more quote
An average bolt of lightning carries a negative electric current of 40 kA, although some bolts can be up to 120 kA, and transfers a charge of five coulombs and 500 MJ, or enough energy to power a 100 watt lightbulb for just under two months. The voltage depends on the length of the bolt: with the dielectric breakdown of air being three million volts per meter, this works out at about one billion (thousand million) volts for a 300m (1,000 foot) lightning bolt. With an electric current of 100 kA, this gives a power of 100 trillion (million million) watts.
No more dish or lmb
Dave