Re: quick question about antennas

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Re: quick question about antennas

Jim Brown-10
On Mon,7/11/2016 2:07 PM, Matt Murphy wrote:
> I am guessing that installing a grounded 240V receptacle and using the
> conduit as ground is *not* up to code.

It depends on the building code used by local jurisdiction. In many
jurisdictions, it IS legal to use conduit as the green wire IF it is
continuous and all the connections are made properly. As I recall, it's
legal in Chicago, where steel conduit is used for almost everything, in
large part to keep union electricians working.

In other jurisdictions, or if the conduit is not properly bonded for the
entire length, a dedicated green wire must be run.

> If it were, then perhaps I could install a NEMA 6-30 receptacle (which
> has a ground pin and two hots).

I don't know connectors by number, but what I would install is a
standard outlet with two hots and ground that is slightly larger than an
ordinary 120V outlet.  Or even two outlets in the same steel backbox,
like a 120V duplex.

73, Jim K9YC

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Re: quick question about antennas

Matt Murphy
Jim --

Ahh, I think that would work.  If the conduit works as ground (which I
think it does here) I could use the kind pictured in the link below, and
wire up a the power cable using the two hots and ground as you recommend:

http://waterheatertimer.org/images/240-Volt-outlet4-253.jpg

73,
Matt NQ6N


On Mon, Jul 11, 2016 at 4:21 PM, Jim Brown <[hidden email]>
wrote:

> On Mon,7/11/2016 2:07 PM, Matt Murphy wrote:
>
>> I am guessing that installing a grounded 240V receptacle and using the
>> conduit as ground is *not* up to code.
>>
>
> It depends on the building code used by local jurisdiction. In many
> jurisdictions, it IS legal to use conduit as the green wire IF it is
> continuous and all the connections are made properly. As I recall, it's
> legal in Chicago, where steel conduit is used for almost everything, in
> large part to keep union electricians working.
>
> In other jurisdictions, or if the conduit is not properly bonded for the
> entire length, a dedicated green wire must be run.
>
> If it were, then perhaps I could install a NEMA 6-30 receptacle (which has
>> a ground pin and two hots).
>>
>
> I don't know connectors by number, but what I would install is a standard
> outlet with two hots and ground that is slightly larger than an ordinary
> 120V outlet.  Or even two outlets in the same steel backbox, like a 120V
> duplex.
>
> 73, Jim K9YC
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
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240V Power Connectors

Jim Brown-10
Assuming you have 20A breakers and #12 or larger copper, you want NEMA
6-20. See this link.

https://en.wikipedia.org/wiki/NEMA_connector

73, Jim

On Mon,7/11/2016 2:43 PM, Matt Murphy wrote:

> Jim --
>
> Ahh, I think that would work.  If the conduit works as ground (which I
> think it does here) I could use the kind pictured in the link below,
> and wire up a the power cable using the two hots and ground as you
> recommend:
>
> http://waterheatertimer.org/images/240-Volt-outlet4-253.jpg
>
> 73,
> Matt NQ6N
>
>
> On Mon, Jul 11, 2016 at 4:21 PM, Jim Brown <[hidden email]
> <mailto:[hidden email]>> wrote:
>
>     On Mon,7/11/2016 2:07 PM, Matt Murphy wrote:
>
>         I am guessing that installing a grounded 240V receptacle and
>         using the conduit as ground is *not* up to code.
>
>
>     It depends on the building code used by local jurisdiction. In
>     many jurisdictions, it IS legal to use conduit as the green wire
>     IF it is continuous and all the connections are made properly. As
>     I recall, it's legal in Chicago, where steel conduit is used for
>     almost everything, in large part to keep union electricians working.
>
>     In other jurisdictions, or if the conduit is not properly bonded
>     for the entire length, a dedicated green wire must be run.
>
>         If it were, then perhaps I could install a NEMA 6-30
>         receptacle (which has a ground pin and two hots).
>
>
>     I don't know connectors by number, but what I would install is a
>     standard outlet with two hots and ground that is slightly larger
>     than an ordinary 120V outlet.  Or even two outlets in the same
>     steel backbox, like a 120V duplex.
>
>     73, Jim K9YC
>
>     ______________________________________________________________
>     Elecraft mailing list
>     Home: http://mailman.qth.net/mailman/listinfo/elecraft
>     Help: http://mailman.qth.net/mmfaq.htm
>     Post: mailto:[hidden email]
>     <mailto:[hidden email]>
>
>     This list hosted by: http://www.qsl.net
>     Please help support this email list: http://www.qsl.net/donate.html
>     Message delivered to [hidden email] <mailto:[hidden email]>
>
>

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Re: quick question about antennas

Elecraft mailing list
In reply to this post by Jim Brown-10
The alternative on a standard duplex box is where the "blades" are at right angles to the normal outlet..  Therefore never allowing a misconnection.
Mel, K6KBE


      From: Jim Brown <[hidden email]>
 To: Reflector Elecraft <[hidden email]>
 Sent: Monday, July 11, 2016 2:21 PM
 Subject: Re: [Elecraft] quick question about antennas
   
On Mon,7/11/2016 2:07 PM, Matt Murphy wrote:
> I am guessing that installing a grounded 240V receptacle and using the
> conduit as ground is *not* up to code.

It depends on the building code used by local jurisdiction. In many
jurisdictions, it IS legal to use conduit as the green wire IF it is
continuous and all the connections are made properly. As I recall, it's
legal in Chicago, where steel conduit is used for almost everything, in
large part to keep union electricians working.

In other jurisdictions, or if the conduit is not properly bonded for the
entire length, a dedicated green wire must be run.

> If it were, then perhaps I could install a NEMA 6-30 receptacle (which
> has a ground pin and two hots).

I don't know connectors by number, but what I would install is a
standard outlet with two hots and ground that is slightly larger than an
ordinary 120V outlet.  Or even two outlets in the same steel backbox,
like a 120V duplex.

73, Jim K9YC

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Re: quick question about antennas

Bill Frantz
In reply to this post by Jim Brown-10
When I wired an addition to our house some 40 or so years ago,
one of my circuits from the service box started in Romex,
converted to steel conduit, and then back to Romex. Since the
grounding connections were properly bonded to each other, the
building inspector in Los Gatos, CA approved it.

The principle reason for the grounding conductor (green wire) is
to cause the circuit breaker to open if one of the hot wires
shorts to the case of the electrical equipment. If the case just
floated, it would be a shock hazard for anyone who touched it
and also touched something that was grounded.

73 Bill AE6JV

On 7/11/16 at 2:21 PM, [hidden email] (Jim Brown) wrote:

>It depends on the building code used by local jurisdiction. In
>many jurisdictions, it IS legal to use conduit as the green
>wire IF it is continuous and all the connections are made
>properly. As I recall, it's legal in Chicago, where steel
>conduit is used for almost everything, in large part to keep
>union electricians working.
>
>In other jurisdictions, or if the conduit is not properly
>bonded for the entire length, a dedicated green wire must be run.
--------------------------------------------------------------
Bill Frantz        | There are now so many exceptions to the
408-356-8506       | Fourth Amendment that it operates only by
www.pwpconsult.com | accident.  -  William Hugh Murray

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Re: 240V Power Connectors

Clay Autery
In reply to this post by Jim Brown-10
Yup...  I've used those...  I am a BIG fan of the twist-lock NEMA 240VDC
plugs/receptacles for the MAIN 240 source coming into movable racks...

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389

On 7/11/2016 5:16 PM, Jim Brown wrote:
> Assuming you have 20A breakers and #12 or larger copper, you want NEMA
> 6-20. See this link.
>
> https://en.wikipedia.org/wiki/NEMA_connector
>
> 73, Jim
>

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Re: 240V Power Connectors

Matt Murphy
I think that since the breaker is for 30A I might just be able to install a
NEMA 14-30 receptacle and connect the equipment ground pin to the steel
conduit using a pigtail (and the two hots and neutral to the corresponding
pins):

http://waterheatertimer.org/images/240-Volt-outlet4-253.jpg

Any cautions against doing this? I believe all the wall receptacles in my
home have the equipment ground pin connected to the steel conduit, and that
there are no separate wires run for equipment ground.

73,
Matt NQ6N

On Tue, Jul 12, 2016 at 9:36 AM, Clay Autery <[hidden email]> wrote:

> Yup...  I've used those...  I am a BIG fan of the twist-lock NEMA 240VDC
> plugs/receptacles for the MAIN 240 source coming into movable racks...
>
> ______________________
> Clay Autery, KY5G
> MONTAC Enterprises
> (318) 518-1389
>
> On 7/11/2016 5:16 PM, Jim Brown wrote:
> > Assuming you have 20A breakers and #12 or larger copper, you want NEMA
> > 6-20. See this link.
> >
> > https://en.wikipedia.org/wiki/NEMA_connector
> >
> > 73, Jim
> >
>
> ______________________________________________________________
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