[TowerTalk] Grounding, Lightning & corona discharge

Alan NV8A (ex. AB2OS) nv8a at att.net
Thu Jul 29 11:34:11 EDT 2004


Similar here, in a 30-yr-old ranch-style house in W Michigan: Elec. at 
one end, gas and phone at the other, cable and dish at the back. I am 
working on getting those grounds bonded together.

Alan NV8A


On 07/29/04 10:58 am Jim Brown put fingers to keyboard and launched the 
following message into cyberspace:

>>Illustrative of the difficulties of doing the single-point ground thing 
>>properly with an old house, our telephone and cable TV connections are 180 
>>degrees around the house from the AC power entrance, grounded to a rod at 
>>that point

> I have a similar problem in my 110 year old Chicago house -- telco on the northeast 
> side of the house, power on the southeast. 
> 
> Last I looked, code says that all grounds must be bonded together. It is NOT legal 
> (nor is it safe) to have things tied to separate rods (or ground electrodes) without 
> bonding those electrodes together.  Ideally those bonds need to be as short as 
> possible and outside the building,  but those two requirements can often be 
> conflicting. If I ran the bond outside my building, it would need to be at least 100 ft 
> long and require a lot of trenching. Inside the building ( basement) adjacent to the 
> grounding blocks, it could be as short as about 30 ft. At 1 MHz (the approximate 
> peak of lightning energy per IEEE) there's a big difference in the inductive 
> reactance. What's a mother to do?  


More information about the TowerTalk mailing list