> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
> Behalf Of Paul Christensen
> Sent: Tuesday, November 03, 2009 8:21 PM
> To: amps@contesting.com
> Subject: Re: [Amps] TL922 Power Plugs
>
> > My Neutral and Ground is connected at the main panel but also at
> > the barn 300 feet away. I am running a 3 wire 100 amp 240v power 4 00
> > aluminum line to the barn from a 100 amp 240v breaker located in my main
> >distribution box. I didn't like the idea of a gnd neutral tie that far
> >away from
> > the barn, so I tied them together at the barn with a second ground rod
> > located
> >at the barn. Is that such a bad idea?
>
> See NEC 250.32(A) and (B). Since your 3-wire system is existing, the 4-
> wire
> requirement beginning with the 2008 NEC likely does not apply -- but may
> under your local code. New detached structure wiring generally requires
> 4-wire service whether or not there is a continuous metallic path between
> structures In no event should the neutral and ground come in contact
> again
> from the feeder path to the barn's sub-panel (as it seems to exists now).
> Being a detached building, the barn service entrance must be
> grounded/bonded
> to its own grounding electrode or grounding electrode system in accordance
> with Part III of NEC Section 250.
>
> Paul, W9AC
Paul,
If I am following what you are saying that is not correct. Under the old
rules with a 3 wire feeder to a detached building the neutral was to be
connected to the neutral and ground buss in the panel in the remote
building. A local ground rod was also to be installed and connected to the
neutral/ground buss at the detached building.
The neutral and ground would also be connected together at the main panel.
They also stipulated that there were not to be any other metallic
connections between the two buildings such as water pipes, phone lines etc.
that could possibly carry any neutral currents inadvertently.
Otherwise 4 wires would be required and the ground/neutral connection in the
detached building had to be then kept separate as the new code states. A
local ground rod connected to the ground buss is still required at the
detached building.
73
Gary K4FMX
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