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Posted By: sparky66wv 250.8 - 06/12/02 12:33 AM
This was found in a bag of S-C-GS-1's (#10x32 ground screws with 1/4" hex heads)...

[Linked Image from users.stargate.net]
[Linked Image from users.stargate.net]

Doesn't the last sentence in 250.8 prohibit this?

"...Sheet metal screws shall not be used to connect grounding conductors to enclosures."

[Linked Image]

Floor sweepin's ended up in the wrong box before they got painted??? Got me...
Posted By: Bjarney Re: 250.8 - 06/12/02 01:17 AM
Musta' been "product waste-reduction week" on the miscellaneous green-dyed screw bulk packaging asssitant inspection team.

An email might get a case of good ones on your doorstep. [Yeah, just what you wanted...exchange it for the cheese wheel.]
Posted By: Bill Addiss Re: 250.8 - 06/12/02 03:49 AM
Virgil,

Some difference in resolution there guy!

Much better!

[Linked Image]
Bill
Posted By: sparky66wv Re: 250.8 - 06/12/02 04:12 AM
Yep, finally got a macro!

2.1 Mega Pixel...

More pix to come!!!
Posted By: Bill Addiss Re: 250.8 - 06/12/02 04:29 AM
Virgil,

Hmm, I double-posted somehow ...
2.1 is good, I got a new one recently too, a 2.3 I think (Ricoh) still haven't had the time to investigate all the features.

[Linked Image]
Bill

[This message has been edited by Bill Addiss (edited 06-12-2002).]
Posted By: amp-man Re: 250.8 - 06/12/02 05:18 AM
I'm thinking that this is a relic from the past...it was only a few cycles ago that sheet metal screws were prohibited.

Like the occasional letter from 50 years ago that gets delivered with today's mail, could this screw have been trapped in a bin for 10 years, and just fallen loose?

Cliff
Posted By: sparky66wv Re: 250.8 - 06/14/02 03:31 AM
Sounds like a good theory to me!

Does anyone remember these being sold as grounding screws?
Posted By: pauluk Re: 250.8 - 06/14/02 08:40 AM
Why were sheet-metal screws removed as an acceptable method of grounding?

Lack of contact area to metal to clear a high-current fault? Possibility of working loose?
Posted By: sparky Re: 250.8 - 06/14/02 11:06 AM
Paul,
i think many were simply using sheet rock screws....
Posted By: Joe Tedesco Re: 250.8 - 06/14/02 11:11 AM
Yes, the proposal was sent in by an electrical inspector in Madison, Wisconsin and his substantiation indicated that sheet metal screws were unreliable when used to secure an equipment grounding conductor to the enclosure. The code uses the term "means provided" in many areas, when the rule covers the termination of the EGC. This "means provided" is usually a threaded hole, or other termination where "GR" or "GRND" will be engraved in the metal.
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