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Old 06-07-2005, 11:40 AM
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Quote:
Originally Posted by onenew32
First off let me say: DAMN, HOW BIG A WELDER YOU GOT?
It's just a 225 AC/DC Lincoln buzz box. I forgot to tell the distance being covered: it's about 125 feet, main panel board to garage panel board.

Quote:
Originally Posted by onenew32
Anyway, now that that is out of the way, let me tell you a few things about me. I am presently not a licensed electrician, but in the past I held both a journeyman’s and a Master electrician’s license in a very large metropolitan city. A career change found me letting these licenses lapse. My knowledge of the National Electrical Code (NEC) is a little out of date, but it is sound. Although some things I have done in my own and friends shop might not follow the exact letter of the NEC as now written, I have never done anything I worried about, or in my opinion would jeopardize anyone’s safety.
That being said, I have questions:
1. Where your garage service is fed from, the primary dwelling, I presume. Does the panel there have bottom or “flow through” lugs at the bottom of the buss to accept wire lugs? Most residential panels don’t, but it would be cool if it did.
It doesn't.

Quote:
Originally Posted by onenew32
2. Do you have a space for a 100 amp breaker in this box, possibly replacing the 40 amp, two pole you have now?
Yes. 7 spaces still unused besides the 2 double pole 50A breakers feeding the garage and the welder.

Quote:
Originally Posted by onenew32
3. Is the garage separated from the house, or attached? If it is detached, the NEC now says it must be treated as a separate structure for the matters of grounding. (a good thing)
Yes. If I decide to replace the existing panel in the garage, I would install the new one just inside the garage at the corner nearest the house. This would reduce the feeder length from the main panel in the house to 105 feet.

Quote:
Originally Posted by onenew32
4. You need to get yourself a book. “Ugly’s Electrical References” Distributed by Burleson Distributing Co, 3501 Oak Forest Drive, Houston, Texas 77018. Your local electrical distributor might have one. Great electrical book for laymen.
Thanks. I have a dog-eared copy of "American Electricians' Handbook", McGraw-Hill, ISBN 0-07-013931-8, 1981.

(How is it that practically every level of government includes the NEC in their regulations, but you have to buy the damned NEC book to know the requirements? Aren't we being taxed to create the laws, then forced to buy the letter of the law from a private organization?)

Quote:
Originally Posted by onenew32
5. Now the important stuff: your 1” PVC conduit will hold two # 2 or 3 #3 THW or THHN (THHN recommended) wire. This will give you a rated 100 amp or 115 amp capabilities. (all NEC ratings are based on THW) using the #2 will require you setting a new ground rod at the shop location for Neutrals and grounds (do it)
So I could pull two #2 wires in each of the two existing conduits and elimate the need for both of the existing 8/3 w/gnd cables in there now? And not have to dig that trench again to replace the 2 small conduits with 1 big one? Example: one "hot" and neutral in one conduit, one "hot" and ground in the other conduit?

Quote:
Originally Posted by onenew32
6. My final suggestion would be to install a new 100 amp panel with about 20 or 24 spaces, feed your welder and compressor from it, and still have 16 single spaces for everything else.
I kept thinking that might be possible but wasn't sure. The handbook I have only includes the NEC up to 1981.

Quote:
Originally Posted by onenew32
7. Keep in mind that the NEC allows for de-rating of conductor size and branch circuit breaker size for welders, based on duty cycle, but the nameplate amps should take priority over that. Unless you have a real Hog, #8 wire should run it. (55 amps)
If I put in the 20 space load center I could use some of this #8 cable as an extension cord for the welder.

Quote:
Originally Posted by onenew32
8. I don’t like “piggy back” or tandem breakers. (but I don’t like fat chicks, either, but some guys are alright with them. It’s a personal thing, I guess).
I don't like them either but if enough advised that it was the best option at this point, I'd try some.

Quote:
Originally Posted by onenew32
9. If you even consider using anything other than copper wire, I will personally send my dog, Bubba to bite you.
heh - All the wiring I've done has been copper. My mother's house was built around 1900 and had its wiring on porcelain insulators. It took me two years of spare time to re-wire it with 12/2 w/gnd NM. It took her at least that long to get used to not having to carry around an extension cord for everything.

Quote:
Originally Posted by onenew32
10. Remember, electrical outlets are never as cheap as they are during construction of a new structure. Put in plenty.
My garage is a pole-barn construction that seems to grow faster than my wiring abilities can keep up with. I've been trying to maintain that thing about an outlet within 6 ft of wall space at any point along the wall. That's why I have only 1 space left in that garage panel.

Quote:
Originally Posted by onenew32
11. Make certain all of your connections are tight. Loose connections build heat, which is not good.
Hmm. Turn 'em until they strip then back off 1/4 turn? Just kidding. I appreciate the warning.

Quote:
Originally Posted by onenew32
12. If you have any concerns about anything I have written here, ask an electrician locally. Shop fires that burn down your wife’s house can be hard to explain to her. After all, I might be a crackpot, or just stayed at a Holliday Inn Express last night.
Actually, I have both a brother and a brother-in-law who are electricians, but I *know* they are crackpots. I just like to get as much info and input as possible when I'm about to get in over my head.

Quote:
Originally Posted by onenew32
13. I hope I have been of some help. Gotta go now, my fingers are starting to cramp. (just the two I type with).
You sure have! Thanks, loads!
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