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Breakers for KPA1500?

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Breakers for KPA1500?

WOW!

Thanks for that link! Now just to find it in PDF.

'73 de JIM N2ZZ

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Mark Goldberg
Sent: Monday, July 09, 2018 8:27 PM
To: hawley, charles j jr
Cc: [hidden email]
Subject: Re: [Elecraft] Breakers for KPA1500?

Actually, if you look at the NEC (National Electrical Code), they have
factors for ambient temp and wire temp ratings. Other codes around the
world are similar.

For example, if you use AWG 12 Type UF cable, the base rating is 20 Amps.
With the temperatures we have in Arizona, where it can get above 140F in an
attic, they have a correction factor of 0.71 if the wire is rated to 90C.
So it should only be used up to 14.2 Amps. If you are installing from
scratch, I would go to AWG 10 just for a safety factor. Of course, you may
not be here in Arizona. It actually may get hotter than that here in some
attics.

You can read the NEC for free by going here and signing up. It will tell
you more than you want to know, in excruciating detail. A copy will cost
ya, but I have found the online interface good enough to find things.

https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-cod
es-and-standards/detail?code=70

73,

Mark
W7MLG

On Mon, Jul 9, 2018 at 4:49 PM, hawley, charles j jr <[hidden email]>
wrote:

> How many watts of heat does the average attic have in the summertime?
>
> Chuck
> KE9UW
>
> Sent from my iPhone, cjack
>
> > On Jul 9, 2018, at 6:39 PM, Josh Fiden <[hidden email]> wrote:
> >
> > If wire run ends up being 50' you could see a 2V drop at 13A. Agree that
> switching supply in amp won't care. 26W of heat in the wire inside a wall
> would bug me.
> >
> > 73
> > Josh W6XU
> >
> > Sent from my mobile device
> >
> >> On Jul 9, 2018, at 3:12 PM, Roy Koeppe <[hidden email]> wrote:
> >>
> >> The KPA1500 uses a regulated power supply: input 195 to 250 vac.
> Voltage loss in #12 wires is so small the regulator will laugh at that.
> >>
> >> 73, Roy K6XK
> >>
> >>
> >> "I would also suggest using three - #10 with ground as the line from
> the
> >> breakers to the amp operating position."
> >>
> >> 73
> >>
> >> Bob, K4TAX
> >>
> >>
> >>> On 7/9/2018 11:43 AM, Roy Koeppe wrote:
> >>> Yes, that is what I am using.
> >>>
> >>> 73, Roy K6XK
> >>>
> >>>
> >>> I probably missed this but my google searches aren't working either.
> >>>
> >>> Will 2x 20A breakers (220v) be sufficient for the KPA1500?
> >>>
> >>>
> >>
> >>
> >> ______________________________________________________________
> >> Elecraft mailing list
> >> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> >> Help: http://mailman.qth.net/mmfaq.htm
> >> Post: 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]
> >
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: 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]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: 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]
>

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: 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]

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: 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]

Mark Goldberg

Re: Breakers for KPA1500?

PDF or printed copy will cost you! But I have searched for a topic on
forums such as Mike Holt's and they usually list a paragraph number. The
online version has a table of contents so you can go there once you know
the paragraph number.

73,

Mark
W7MLG

On Mon, Jul 9, 2018 at 6:35 PM, James F. Boehner MD <[hidden email]>
wrote:

> WOW!
>
> Thanks for that link! Now just to find it in PDF.
>
> '73 de JIM N2ZZ
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Mark Goldberg
> Sent: Monday, July 09, 2018 8:27 PM
> To: hawley, charles j jr
> Cc: [hidden email]
> Subject: Re: [Elecraft] Breakers for KPA1500?
>
> Actually, if you look at the NEC (National Electrical Code), they have
> factors for ambient temp and wire temp ratings. Other codes around the
> world are similar.
>
> For example, if you use AWG 12 Type UF cable, the base rating is 20 Amps.
> With the temperatures we have in Arizona, where it can get above 140F in an
> attic, they have a correction factor of 0.71 if the wire is rated to 90C.
> So it should only be used up to 14.2 Amps. If you are installing from
> scratch, I would go to AWG 10 just for a safety factor. Of course, you may
> not be here in Arizona. It actually may get hotter than that here in some
> attics.
>
> You can read the NEC for free by going here and signing up. It will tell
> you more than you want to know, in excruciating detail. A copy will cost
> ya, but I have found the online interface good enough to find things.
>
> https://www.nfpa.org/codes-and-standards/all-codes-and-
> standards/list-of-cod
> es-and-standards/detail?code=70
>
> 73,
>
> Mark
> W7MLG
>
>
> On Mon, Jul 9, 2018 at 4:49 PM, hawley, charles j jr <
> [hidden email]>
> wrote:
>
> > How many watts of heat does the average attic have in the summertime?
> >
> > Chuck
> > KE9UW
> >
> > Sent from my iPhone, cjack
> >
> > > On Jul 9, 2018, at 6:39 PM, Josh Fiden <[hidden email]> wrote:
> > >
> > > If wire run ends up being 50' you could see a 2V drop at 13A. Agree
> that
> > switching supply in amp won't care. 26W of heat in the wire inside a wall
> > would bug me.
> > >
> > > 73
> > > Josh W6XU
> > >
> > > Sent from my mobile device
> > >
> > >> On Jul 9, 2018, at 3:12 PM, Roy Koeppe <[hidden email]> wrote:
> > >>
> > >> The KPA1500 uses a regulated power supply: input 195 to 250 vac.
> > Voltage loss in #12 wires is so small the regulator will laugh at that.
> > >>
> > >> 73, Roy K6XK
> > >>
> > >>
> > >> "I would also suggest using three - #10 with ground as the line from
> > the
> > >> breakers to the amp operating position."
> > >>
> > >> 73
> > >>
> > >> Bob, K4TAX
> > >>
> > >>
> > >>> On 7/9/2018 11:43 AM, Roy Koeppe wrote:
> > >>> Yes, that is what I am using.
> > >>>
> > >>> 73, Roy K6XK
> > >>>
> > >>>
> > >>> I probably missed this but my google searches aren't working either.
> > >>>
> > >>> Will 2x 20A breakers (220v) be sufficient for the KPA1500?
> > >>>
> > >>>
> > >>
> > >>
> > >> ______________________________________________________________
> > >> Elecraft mailing list
> > >> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > >> Help: http://mailman.qth.net/mmfaq.htm
> > >> Post: 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]
> > >
> > > ______________________________________________________________
> > > Elecraft mailing list
> > > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > > Help: http://mailman.qth.net/mmfaq.htm
> > > Post: 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]
> > ______________________________________________________________
> > Elecraft mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/elecraft
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: 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]
> >
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: 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]
>
>