[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [TCML] comments on designing a lightning protection system



 
 
In a message dated 6/6/08 8:49:41 A.M. Eastern Daylight Time,  
fxrays@xxxxxxxxxx writes:

>2) A handrail is comprised of jointed sections that are not  designed 

>to be electrical connections. If it were a true ground, every  




>connection would have to be either strapped or soldered. Cold  

>connections are not allowed. Even if the handrail was grounded, it  is 

>not a good, reliable conductor.

>3) A handrail is usually galvanized steel pipe, not a good  conductor 

>of electricity.
    FWIW, plain ol' EMT (Electrical Metallic Tubing) is  very widely used as 
electrical conduit in commercial and industrial  installations. It's joined 
with cold connections, not strapped or soldered. It's  also thin galvanized 
steel pipe. In the event of a ground fault, it's expected  to carry fault currents 
of up to 200kA until the upstream device (fuse or  breaker) clears the fault.
    Yes, the Code can allow it to be the only ground  path. But it's always 
wise to run a ground wire inside EMT, since the  connections are highly 
susceptible to damage (separating).
    BTW, galvanized steel pipes are in general pretty  good conductors of 
most kinds of electricity. What's the *best* possible  conductor to use to 
channel lightning? Heavywall large-diameter silver pipes  braided into a Litz cable?
 
-Phil LaBudde
Center for the Advanced Study of Ballistic  Improbabilities



**************Get trade secrets for amazing burgers. Watch "Cooking with 
Tyler Florence" on AOL Food.      
(http://food.aol.com/tyler-florence?video=4?&NCID=aolfod00030000000002)
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla