ECN Electrical Forum
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Holy cow Reno!! If you're gonna write a reply at least spell the words right!It's It's "getting" not "gettig", it's "to"
not "ot" (OT is when you work late for more money)and
trinng shoes aren't available anywhere. Aside from that, your
reply was A+ and you had some great points. Especially the
steel stud part even though you spelled holes wrong. Keep up the good work sir!!

Well, I sure had that coming ....

I also really miss the edit button - oh well. Point made, and reply accepted with grace.

I believe that 250.8 still applies here because the base of the relay must be grounded or bonded to the enclosure. Teks screw( so sorry for the improper moniker ) are a form of sheet metal screw and to my knowledge are not thread-forming machine screws that engage not less than two threads in the enclosure as required by the code. I believe that they may work fine for holding studs together but they are not approved for grounding or bonding. I have written many violations where someone has used a “Teks” screw to secure a lug to a panel or enclosure and will continue to do so until someone shows me where they are rated for that purpose.

Regards,

Tony

The base of that contactor is not a conductor nor a jumper.
I am forced to read the words of the code and enforce them. I can't make things up.
I also wonder how much evidence there is that these provide a less than satisfactory mounting strength.
I asked before, how do you attach boxes to metal studs?
I see them using self drilling thread forming screws.
There is certainly a lot more direct force applied to a receptacle box with plugging and unplugging than you have with a contactor making and breaking. In Florida that is also how you bond the steel studs.

To drag this back on topic I will agree with those who say there may be a difference between a pull box and a cabinet.
I am just not sure what it is.
If you were concerned you would be looking for proof that the enclosure was evaluated to UL50 standards.
The same standard applies to Junction and Pull boxes (BGUZ) and Cabinets and Cutout boxes (CYTV) so this seems to be a distinction without a difference.
Personally I would be a lot more concerned with the weather rating, wire bending space and the usual stuff. I might think the self drilling thread forming screws were an expedient but I would be hard pressed to see the violation.
I don't like tywraps either but I hold my nose and let them go.

Greg:
So we don't get off on the wrong foot here..

Teks (Tek) screws are what is used for metal stud assembly, and what is commonly used to mount boxes to metal studs.

I think if my within comments were read, I eluded that I would not write a 'red' for what the OP said, all I was getting into is reasoning why it was an issue for a 'red'.

I am a bit confused .... I've never seen any sort of relay / contactor / starter / overload / whatever where the base had to be grounded. That is, the body of the device was grounded by its' mounting screws.

All I can remember seeing were components made of some non-conducrive material. The only terminals provided were for the load-carrying conductors and control wires - not even a place for attaching a bonding jumper.

Now, if you're saying that the enclosure must be bonded, pull boxes have their own points that are specifically prepared for accepting a green screw. This location is distinct from the mounting holes.



Maybe we're thinking different thinngs when we say 'contactor.'

I don't think there is a requirement for the base to be grounded, it just happens incidentally in a metal box.

That's my point, Greg ... I don't care how you fasten plastic, or bakelite, or whatever they make contactor of, to a metal bok .... what are you grounding? The only conductive parts that are exposed are 'live,' and you surely wouldn't want them bonded.