If the neutral conductor should become interrupted due to corrosion, loose
connection or improper repairs, it could become electrically live from one
of the hot lines through any connected load. If the grounding conductors and
metal parts connected to them are connected to the neutral, then the boxes,
cabinets, etc. also become electrically live and likely to cause damage or
injury. If the grounding conductors are not connected to the neutral
anywhere except on the input side of the neutral break, this cannot happen.
Just gives a little extra protection in case something goes wrong, which is
the reason for a lot of safety rules.
Don Young
"Ken Hall" wrote in message
...
On Sun, 24 Apr 2005 17:28:23 GMT, larry wrote:

I got "the book", the new one, out of the truck-

since 1999, the nec requires neutral and ground on everything, no stove
and dryer 3wire outlets.

Thanks much for the info.

With the exception of devices using one of the 120 legs for something,
it's still not clear to me the reason for this rule.

Ken