"terry" wrote in message
...
On Oct 14, 9:46 pm, Rick-Meister wrote:
You cannot use the conduit as the grounding conductor. Not anymore, at
least. Latest code says use a separate grounding conductor and bond it
to box.



On Tue, 14 Oct 2008 14:59:41 -0700 (PDT), wrote:
I'm using rigid steel conduit with steel boxes where I have elected to
use the conduit as the grounding conductor. I have a 1/2" conduit
going into a masonry box with concentric 1/2 & 3/4 knockouts. I'm not
crazy about concentric KO's so I thought I'd knock out to 3/4 and use
a 3/4 to 1/2 reducing bushing where the conduit enters the box. (In
this case it would actually be an "expanding" bushing.) ... and a
locking nut on both sides of the
connection.

Isn't what I propose better than using the 1/2 knockout then praying
that the 3/4 knockout doesn't come loose? -- better for insuring a
good ground? The code does not say much about reducing bushings. I
really rather not run a separate grounding conductor.

--zeb- Hide quoted text -

- Show quoted text -

Yes that also would be my understanding for any 'new' work; to current
codes.
Existing conduit previously used as grounding 'might' be grandfathered
although some jurisdictions inspections may reject it if other work is
being done in same area.

It's perfectly acceptable by current NEC