Could someone please tell me the NEC article which states the line has to be on top and load on the bottom of a breaker or disconnecting means. I have done it that way forever and now need to prove where it is located in the NEC. Or is it?

Thank You,
Tom

Merry Christmas to all and a very safe Holiday.

That is not in the NEC, BUT

If the CB is marked " Line " then the incoming power is connected to the " Line " terminals of the CB what-ever the position ( top, bottom, sideways. 110.3(B).

My understanding of line load was always manufacturers specs. I might be wrong but I don't belive there is anything in the code book for this.

IMHO, think about this:
The "line" side of a fused disconnect is connected to the bottom lugs.....you "open" the disco to replace a fuse....the fuse is "hot", and so are the knives that you opened.....

How many of us have come upon this scenario??

Just put a untrained person, DIY'er, homwowner, or the new apprentice in the above situation!

How about the guys that "back feed" a 2 or 3 pole CB???

Manufacturers instructions are supposed to be followed. Somewhere there is/was a reference about the disconnect switch isolating the fuses when the switch was "open".

John

One old reference in the code to all knife blade disconnects not to be installed as to allow gravity to close them.

Article 404.7 requires that on vertically mounted swiches the up position of the handle shall be the on position.
I also recall the explanation that refers to gravity tending to open a switch as opposed to closing it.

HotLine's post brings up another point.
When testing (always) disconnects and breakers, be sure to not only test line to ground, but line to line as well, lest you run into an ungrounded delta system that will show no voltage to ground (but might be hot 480).
Some of the younger folks have worked just on Y systems, and the delta never even seems to enter their minds.
Just the thought of it makes me ill ...S