Replies

1. 
   MHBurton | Sep 25, 2005 04:17pm | #1

   Good Lord!! I am an Gas Plant Electrician by trade, and that enclosure he used probably cost more than the equipment it is running. Hah! Hah!

   Michael Burton
   Thunderbird Hardwoods
   KD Mesquite
   Llano, TX

1. 
   maddog3 | Sep 25, 2005 04:42pm | #2

   ,,,by an order of magnitude at least , that is a beauty isn't it MH ?"

1. 
   MHBurton | Sep 26, 2005 02:43am | #3

   I looked at the photo again and there is another enclosure of the same type in the background on another machine.Michael BurtonThunderbird HardwoodsKD MesquiteLlano, TX

1. 
   maddog3 | Sep 26, 2005 08:34am | #10

   ..Indeed there is, well there's several $K in used parts ....."

2. 
   dirtstirrer | Sep 26, 2005 04:06am | #4

   Kind of make all the factory stuff look, well, pathetic.  What on earth were those made for?

    

   Steve
1. 
   dukeone | Sep 26, 2005 05:58am | #5

   D.S.; That is an explosion proof enclosure probably a motor starter. These type enclosures are heavy, expensive ( an understatement!!) and hard to work on because not only does everything have to be just so but they are closed with a latch and then you have bolts all around the mating surfaces which have to be tightened every time. The wires all feed though a sealing fitting which is filled with a plaster like material to prevent any flammable gas from migrating through the conduit and also to keep any sparks from reaching any gas. Any time you need to add a wire you need to chop out the filler (I forget what it is called) or replace the fitting. Any refinery or other such location is full of these, gas stations, paint spray areas etc. Big section in the National Electric Code on it with many details and different gases and dusts have there own sub-sections. Acetylene is the most flammable gas according to the NEC, it is class 1 all by itself.

   KDM (retired electrician)Kenneth Duke Masters
   The Bill of Rights
   December 15 1791
   NRA Endowment Member
   LEAA Life Member
   CRPA Member

1. 
   dirtstirrer | Sep 26, 2005 07:16am | #6

   Ahh, pretty much what I suspected.  Glad I don't have a reason to learn more about them first hand.  Does indeed sound like a pain.  What does a new one run?  I've bought a few contacts for 100 hp. motors that lightning fried, and thought that was bad enough.  I bet these are more.  Learn something everyday. 

    Steve

1. 
   dukeone | Sep 26, 2005 07:41am | #7

   Steve; Don't remember exactly but most every thing involved with explosion proof is expensive and complicated. And any screw-up can be truly spectacular! DukeKenneth Duke Masters
   The Bill of Rights
   December 15 1791
   NRA Endowment Member
   LEAA Life Member
   CRPA Member

1. 
   dirtstirrer | Sep 26, 2005 07:47am | #8

   One of those goofs that would be hard to hide...Steve

2. 
   Stuart | Sep 26, 2005 05:08pm | #11

   I can't tell exactly what the devices in the picture are, but as an example I looked in my Means estimating guide to see what a 30 amp, three pole, unfused local disconnect switch costs. A regular switch costs around $200 or so, but an explosion proof switch is going to be more like $1200. When you throw in installation costs (and explosion proof equipment takes longer to install), the rigid steel conduit and conduit seals that are required, etc., etc. it gets really expensive.

1. 
   Jimma | Sep 26, 2005 05:51pm | #12

   I wondered what happened to my razor motor . . .

2. 
   maddog3 | Sep 26, 2005 06:38pm | #13

   ......mach 4000?"

3. 
   dirtstirrer | Sep 26, 2005 11:25pm | #14

   Egads!  I'll try to avoid needing any of those buggers.

    Steve

4. 
   Elcoholic | Sep 27, 2005 12:33am | #15

   Another interesting factoid - The top and bottom housings are threaded.  The threads have a precisely engineered and machined amount of slop.  When an explosion occurs inside the housing the force pushes the covers outward tightening the threads which allows the hot gasses to be released slowly enough that they've cooled well below the ignition point of the surrounding atmosphere.  The National Electrical Code has a very specific harardous area classification system for various combustible dusts, gasses and fluids.John O'Connell - JKO Handcrafted Woodworking

   The more things change ...

   We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized.  I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.

   Petronious Arbiter, 210 BC

5. 
   maddog3 | Sep 27, 2005 02:07am | #16

   every good shop should have ......two"

2. 
   maddog3 | Sep 26, 2005 08:23am | #9

   ..........Chico?"