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	Subject - 250.4(A)(5) Ryan_J If I am using a metal raceway (aluminum or steel) as an equipment ground, as permitted in section 250.118, am I guaranteed compliance with 250.4(A)(5)? I am curious to hear some thoughts on this. What if the length is 500'? EDIT: Sorry Scott, I didn't see that you had a bonding section here. Please feel free to relocate the thread if you like. JimmyDee Not necessarily. I think the key here is too provide a low-impedance circuit capable of safely carrying the maximum ground-fault current. I can see where perhaps on an excessively long run, it might not be enough. Keeping in mind that the size of the raceway increases as the copper size increases I would have to say maybe. I have been told by some really old, old timers that BX use to start fires when the wrap became insulated, in an old building, with dirt. If I remember correctly, 35' of the old style BX (before the ground ribbon) when shorted at the end with a 15 amp would not blow the fuse. What happened is the steel casing, instead of being a continuous steel sleeve, became a ribbon of about 3.141 times as long and was a great heating element. Jim Ryan_J There is a very cool software that can be downloaded that will help answer this burning question. Go here to download it if you would like...I think you will enjoy it. http://home.comcast.net/~gemi-site/ JimmyDee I downloaded the program and looked it over. Came to the conclusion that I've gone 40+ years with out understanding this and can probably go another 40 without. I admire those of you that can use this stuff but I' too old to think that hard, soooo I'll head on over to the easier stuff. Jim Scott Vickrey No problem Ryan I just created it. I like that program even though some of it is beyond my understanding.