Re: TI-H: hey i have a question.

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Re: TI-H: hey i have a question.


Just don't touch the active pin of the transistor when you've got 3 car
batteries and a 700watt microwave transformer hooked together.  :)  Thats
the only "bad" part about it.  Other than that, you can make a great UPS
for under $100.  You have to have a fast acting high power relay, and your
car batteries should be able to do atleast 1,000 amps surge.  Thats enough
for about a mid sized computer system.  A standard computer system will use
10 amps at 12 volts and when the power dies, the startup amperage is about
60 amps.  One car battery would provide about 15 minutes of backup power
about 4 times.  if you want a good UPS, get golf cart batteries.  They are
made for deep discharge.

My computer will run with 100-130volts.  That means my UPS dies when the
batteries are at about 10 volts, where they are 14 fully charged.

1 AMP of AC power = 5amps at 12 volts

When ever you are dealing with cheep junk like microwave transformers, add
2-3 amps.

1AMP of AC powr = 7-8 AMPS of DC power at 12 volts. (transformer load)

Don't skimp on your transformers.  it is easy to blow a transformer.  make
sure it can withstand high internal temperatures and I recomend a 5 inch
cyclone or squirl cage fan to cool the thing off.

Buy a real transformer if you plan to run anything over about 3 amps.
Microwave's transformers weren't made for constant load.

And test the thing on a 1$ grage sale TV or a light bulb.  I made a dual
transformer version that blew the living out of a 60watt light bulb....
Problem?  I forgot to connect one of the wires on the second transformer to
the correct place.  :)  The bulb wasn't expecting 180 volts or what ever it
was getting.

I had plans for this once...  I guess I can dig them out.  I made my first
100watter' when I was in 6th grade.  If you realy get into electrical
120volt devices in your car, go to a small engine repair shop and find one
of the tiny alternators used in those 500 watt 2 cycle generators.  it
shouldn't be too hard to belt it to your engine shaft.  :)

Grant

>I'm not touching this one with a ten foot pole.
>
>-Gabe
>-----Original Message-----
>From: StoryTelr Jedi Knight <storytelr@yahoo.com>
>To: ti-hardware@lists.ticalc.org <ti-hardware@lists.ticalc.org>
>Date: Sunday, September 20, 1998 2:03 PM
>Subject: TI-H: hey i have a question.
>
>
>>
>>k now if someone wanted to oh... hook Christmas lites up on his car,
>>and use them while driving and/or a display of school and christmas
>>spirit.  what sortof a power source, or converter would one need????
>>
>>i mean like a portable generator or a converter on the cigerette
>>lighter, the type of christmas lites would be either indoor, or
>>outdoor lights, and i live in canada, if that helps with any wattage
>>conversions.
>>
>>
>>- nathan wainwright(StoryTelr@yahoo.com)
>>
>>
>>
>>
>>==
>>A rose is a beautiful thing,
>>A sunset is a gorgeous sight,
>>but the one thing that is best of all,
>>is someone to see it with.
>>
>>- StoryTelr August 6th, 1998 2:31 am
>>
>>_________________________________________________________
>>DO YOU YAHOO!?
>>Get your free @yahoo.com address at http://mail.yahoo.com
>>
>>
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