Ground Bar

[don_resqcapt19]

FWIW siemens says their (true) panelboard cabinets are 16 gauge. I dont know about their loadcenters.

Typically the "commercial" cabinets are thick enough to engage two threads of a screw having 32 threads per inch.

The ones where you see the metal pushed out on the back side at the factory locations for grounding connections are the ones that you cannot drill and tap your own holes for grounding connections.

Note the the term "load center" is just a marketing term for a lower quality panelboard. The term load center is not found in either the NEC or the product standards for panelboards.

 

[jaggedben]

Typically the "commercial" cabinets are thick enough to engage two threads of a screw having 32 threads per inch.



The ones where you see the metal pushed out on the back side at the factory locations for grounding connections are the ones that you cannot drill and tap your own holes for grounding connections.
...

Just took a quick look at the residential "load centers" in our shop and they all look like 16 gauge steel and none have the 'pushed out metal' feature. So at this point saying that only 'commercial' cabinets can be drilled and tapped seems to me probably out of date for new equipment.

The only item I could find with the 'pushed out metal' feature was a discarded 60A light duty unfused disconnect removed from an old site. It did look like thinner steel. I can't say I can clearly recall seeing that feature on any panelboards, let alone any made in the last 40 or so years.

YMMV

 

[don_resqcapt19]

Just took a quick look at the residential "load centers" in our shop and they all look like 16 gauge steel and none have the 'pushed out metal' feature. So at this point saying that only 'commercial' cabinets can be drilled and tapped seems to me probably out of date for new equipment.

The only item I could find with the 'pushed out metal' feature was a discarded 60A light duty unfused disconnect removed from an old site. It did look like thinner steel. I can't say I can clearly recall seeing that feature on any panelboards, let alone any made in the last 40 or so years.

YMMV

have never seen a "load center" that didn't have the pushed out holes for the grounding connections...but have not seen all of the brands.

 

[mtnelect]

This might help to explain.