If we continue to insist that 250.8 requires listed grounding screws a few things come to mind, which have been mentioned before.

1)There would be no need to specifically say:

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

2)As I can not find UL listed 'grounding screws' the use of the green ground screws is as much a violation as using the clamp screws.

This (as Don pointed out) leaves us with the only listed product for the job being a 'grounding clip' and it in no way provides as secure connection as a machine screw.

3)We all clearly know that we can use a unlisted nut and bolt to connect wire terminals of ungrounded, grounded and grounding conductors.

I can say that the AHJ in the States I work accepts standard machine screws to bond a device box. [Linked Image]

Bob

[This message has been edited by iwire (edited 05-22-2004).]

Bob Badger
Construction & Maintenance Electrician
Massachusetts