Re: Dumb Question From A Lady

I read in sci.engr.electrical.compliance that Virginia Belle
<[EMAIL PROTECTED]> wrote (in <[EMAIL PROTECTED]
2237.public.lawson.webtv.net>) about 'Dumb Question From A Lady', on
Wed, 19 Nov 2003:
>I Know that this is a dumb question but, I am curious anyway. 
>
>Lets just say that I need an 18 volt DC power source and that the source 
>has to come from one of those transformers? that plug into the wall and 
>change AC to DC.
>
>What if I only have two of those transformer devices that are 9 Volts DC 
>each.
>
>Now, If I cut the insulation off of the ends of both of those 
>transformers, take the two wire ends from each and twist the 4 ends 
>together to make two again, plug them in, will THAT make me the 18 volts 
>that I need? 
>
>9 + 9 makes 18 doesn't it?
>
>PLEASE tell me that I have made SOME sense here? 

Some , but not a lot. Yes.. 9 + 9 = 18, but to get 18 you have to
connect the wires 'in series'. I'll try to make a diagram. You need to
use Courier (or Courier New) font to see it correctly.

        .....
trans- |     |----------  inner/colour 2
former |     |
       |.....|----------. outer/colour 1
                        |
        .....           |
trans- |     |----------. inner/colour 2
former |     |
       |.....|----------  outer/colour 1
       
You ALSO have to get the correct two wires joined together. If the two
transformers are identical, and they have the normal concentric plugs on
the ends of the output cables, then the words on the diagram tell you
how to connect them. If they have different colours, you can go by them,
e.g. black, white joined to black, white. If not, it's not possible to
tell you unless you understand the terms 'positive' and 'negative' AND
you can identify which wire is which polarity.
-- 
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk 
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