On Tuesday 06 October 2009, Dave wrote: >If I had my druthers, aluminum wire and terminal blocks would not be >used also .... >But cheapness pervades.. > >I've been doing control and power engineering work for about 30 years >now and I have only seen a few instances where alum entrance cable has >screwed up. > >Usually because it wasn't prepped properly. But you are right, if you >want bullet proof reliability you don't use alum in electrical >installation. I am sure that the space shuttle does not have any >aluminum terminal blocks in it! > >Still, try and find a heavy junction power block for industrial use that >is not alum.... It is pretty much impossible.
Yes, a box I put in to service a standby tx about 5 years ago was all alu for its buss bars. Needless to say, all the connections have been re-snugged, several times although its actually wired with copper. >That is also pretty much all the power company will run any longer. I >have some new 15KV lines on the poles in front of my place and they are >all twisted alum cable. > And you would be wise to cop a feel of the crimp sleeves at your weather head occasionally. >>>Chuckle, with suitable emphasis on the cheap part Dave. Copper is plumb >outta sight now. > >Actually it has come down a lot. A 500 ft roll of THHN 10 gauge stranded > was over a hundred bucks a roll for a while. Ouch! >The last I checked it is about $55 now. It is sort of like gas at $2.30 a > gallon, it is cheap compared with $4.50! ;-) Sound like I better go stock up on a box of 12-2/wg then, I'm getting low. >The copper ground/neutral bus bars I bought at the local home store > recently for a star ground central point were about $6.50 each. Cheap by > industrial prices ... Yup, considering there is more machine work in making it than there is material in it, that 'work' is what we pay for at the end of the day. >I was talking with a customer of mine today... They were talking about > some slide mechanisms that had to be replaced on a machine I helped > install last year.. The replacement parts being discussed were "only" > about $10K they said.... So everything is relative. :-) "Only" eh? But you are correct. In broadcasting, I am constantly amazed at how somebody can take 75 pounds of sheet alu, heliarc weld it into a specific shape for an RF mask filter, and get nearly $20k for the finished product. Until you realize that every dimension in it, is calculated to a tolerance of maybe .005", and it still has adjustment screws they tune once and locktite forever, or until it gets abused and dented. Since this stuff is usually installed on the tx output lines, its normally about ceiling high, catches more hell from the errant stepladder while replacing lamps than anything else. The cost of something is always relative to the cost of the something it goes with. A basic truism. [...] -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. <https://www.nrahq.org/nrabonus/accept-membership.asp> All phone calls are obscene. -- Karen Elizabeth Gordon ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
