Date: Tue, 5 Apr 2005 11:34:23 +0200
Reply-To: Joy Hecht <jhecht@ALUM.MIT.EDU>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Joy Hecht <jhecht@ALUM.MIT.EDU>
Subject: Re: DC party lights
In-Reply-To: <425165D7.3000006@mchsi.com>
Content-Type: text/plain; charset="us-ascii"
No, they don't teach that stuff in 8th grade science. At least they didn't
when I was in 8th grade, which was a good while ago. Wish they had, it
would have been much more useful than whatever we did learn.
Joy
****************************************************************
Joy Hecht
and Matilda, 1989 Burgundy Vanagon
For musings about life and the vanadventures:
http://users.rcn.com/jhecht/gypsy
****************************************************************
:::-----Original Message-----
:::From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf
:::Of Al and Sue Brase
:::Sent: Monday, April 04, 2005 6:06 PM
:::To: vanagon@GERRY.VANAGON.COM
:::Subject: Re: DC party lights
:::
:::BA:
:::I'm no EE, but I did sleep at a....
:::Watts is Volts x Amps. (at a power factor of 1.0, anyhow!)
:::So, if a 120 watt string of lights takes 1 Amp at 120 Volts, and if you
:::are lucky enough to find a similar string of lights made for 12 Volts,
:::it would need 10 Amps to put out the same amount of light. At 10 Amps,
:::those hair thin wires would be lighting up almost as much as the bulb
:::filaments. They would need about #16 AWG wire to carry 10 amps.
:::This is what the classical struggle between Edison and Tesla was all
:::about. (when was that 1880's?)
:::And it's called TRANSMISSION. And it IS somewhat related to that thing
:::under your car. (in principle.) That's why those cross country power
:::lines have 18 insulators holding each wire - they are 175,000 volts.
:::Well, you CAN run stuff off your battery, but precious little
:::without..... MONSTER CABLES! 18 year old boys know this! At least those
:::that dream of 1000watt subwoofers.
:::Don't they teach this stuff in school anymore? Like in 8th grade
:::science class?
:::Al Brase
:::
:::BA wrote:
:::
:::>On Sun, 03 Apr 2005 20:00:28 -0400, you wrote:
:::>
:::>
:::>
:::>>I'm looking to get a string of party lights to hand from my awning.
:::>>I've seen some that have a DC plug on them but it really cuts down on
:::>>the selection. Is it possible to just cut off the AC plug and splice on
:::>>a cig lighter DC style plug?
:::>>
:::>>thanks
:::>>
:::>>JFF
:::>>
:::>>
:::>
:::>
:::>Nope. There are power issues ... I don't entirely understand it but
:::>that's because I got my EE degree (barely) many years ago, and I've
:::>forgotten most of it (what I do for a living is software rather than
:::>EE hardware).
:::>
:::>You can buy 12V strings of party lights, They're not cheap - not even
:::>at WalMart. And as you've noticed, the selection is limited.
:::>
:::>If you google, you can find people who have converted AC strings of
:::>lights to 12V DC. There's something about turning a serial string of
:::>120 V AC into parallel strings of 4 lamps each for 12V DC. That
:::>"sounds" right to my vague EE memory ...
:::>
:::>My hero S saved me from having to re-learn enough to do it by
:::>installing an inverter so I could run standard strings of party lights
:::>from our aux battery. But as it happens, I just run the party lights
:::>when we have an electrical hookup.
:::>
:::>
:::>B(&S)
:::>'87 Westy 'Esmerelda Blanc'
:::>SoCal
:::>
:::>
:::>
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