The dude wrote:

SteveBell wrote:
The dude wrote:

kpg wrote:
"John Grabowski" wrote in
:
It sounds as though your wiring is in complete violation of
the National Electrical Code. #12 wire is rated for 20 amps
and should have a 20 amp circuit breaker protecting it. The
three wire plus a ground rod set up for a detached building
is no longer permissible under the 2008 code. You need the
four wires. Using the bare wire in the cable as a neutral is
not allowed. You are seeing current on the ground rod because
you do not have a good neutral connection. The ground and
neutral must be separate at a subpanel. That connection
together is only made at the main panel or the meter. Romex
is not approved to be used underground even though it is in a
pipe. You need to use conductors such as THWN or type UF
cable in your PVC pipe. You are not seeing any current on
the ground rod connected to your main panel (Assuming it is
connected properly) because you have a low resistance
neutral conductor to carry the current back to the
transformer.

Well, yes. That all sounds correct. Thanks.
So if one has an older detached garage with only 3 wires running
is it safe? It has been this way since 1942....

I wanted to replace the fuse panel with a breaker box and was
going to add a ground wire near the garage - I guess this is not
good to do.

Any time you update pretty much anything in a structure, you're
required to update all affected systems to the latest code
requirements. Whether you can get away with replacing a fuse panel
without replacing the wiring is a question for the guy who will do
the inspection. You do know you'll have to have an inspection,
don't you? Few areas let you get away with wiring changes on your
own any more.

Call the permit office in your town, and ask them what they require.

I will have to see, I am not in town. I am in a rural area.

Well, you might be one of the exceptions.
Call the county.

--
Steve Bell
New Life Home Improvement
Arlington, TX