DIY transformer ...

[DeepCut]

Hi z.

These are my wire specs (Standard Wire Gauge, UK style):

0.250mm (#33 SWG)

0.348 ohm/mtr

It doesn't arc, i would like to see that. I'm replicating a work-in-progress so it's kinda off-beat. I'm just in love with the concept, it's like a pulsed induction-generator with only one magnet and one phase.

My current must be ok though because i have shocked myself twice and it made me yelp both times !

I like the sound of your alternator. Will you be able to wind your new wire today also ?


Gary.

[mscoffman]

From your 5 Watts in 60 watts out thread...
"The drive coil is the usual bifilar, 800 turns of 0.30mm and 0.28mm.

The output coil is just over a kilometre (1145 metres) of 0.25mm magnet wire."

A kilometer of wire of .25 mm wire?  388 ohms resistance?  That's like 10 mil
wire, like #30.  At what did you say 200 Volt output.  Probably the only reason
you are developing that kind of voltage is because you have so much resistance
in you wire.  You made a mini Tesla coil.  Like a voltage magnifier.  So like a
Tesla coil it is all voltage.  Get the output wires close together and see if it arcs.

I am in a similar situation.  I'm building an alternator.  I undertook a massive
effort that took months, and was very expensive.  I do have a really nice alternator,
but its performance is pitiful.  It develops 90mA, it should be developing 10s of Amps.
And the problem is the coil.  I picked the wrong wire, and the result is poor performance.
I used 22 AWG wire, which is 15 mils (.38mm), an the coil resistance is 50 Ohms.
With a 65 Ohm load on the coil it only develops 5.84 Volts.  That is a current deficiency.
So, I am replacing the wire with 14 AWG, 68 mils (1.72mm).  The calculated coil resistance
will then be 0.1 Ohms, and I measure it again when I get it assembled.  Maybe I'll get
a little more current, hoping for 10 Amps, at least.

So I gotta say been there done that.  Try putting a neon indicator lamp on the output
leads.  This is a replication, right?  Did you very carefully and precisely duplicate the
device that you are replicating?  The devil is in the details...

Wish you luck, I'm off to disassemble my alternator.  Should get the new wire today...

@z.monkey

Remember, that magnetic field strength is proportional to "ampere-turns"
of the coil. So even though you can flow more current, you have to
keep the number of wire turns up. Usually the coil represents somewhat
of a trade off between volume of the coil and the number of turns,
so the simultaneous changes of parameters can cancel the desired
effect somewhat, even though lower coil resistance should help. One
idea would be to rewind it but then use an external transformer where
the coils are less constained for space.

:S:MarkSCoffman

[z.monkey]

I like the sound of your alternator. Will you be able to wind your new wire today also ?

I get the wire today, then I have to take the alternator all the way apart, unwind the coil, rewind the coils, so maybe a couple days...

Mark, yeah I know, thought this through...

[DeepCut]

I'm getting one of these today :

http://www.wickes.co.uk/Pushfit-Pipe-Connector/invt/431905

It will decrease friction on the axle, which is the main enemy of my RPM at the moment.

Funny the things you end up buying in this endeavour !

[z.monkey]

Funny the things you end up buying in this endeavour !

Today I needed wax paper, and double sided tape...