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[email protected] Daniel47@teranews.com is offline
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Default Variac current question

Lieutenant Scott wrote:
On Mon, 07 Jan 2013 15:25:06 -0000,
wrote:

Lieutenant Scott wrote:
On Sat, 05 Jan 2013 11:30:14 -0000,

wrote:

Lieutenant Scott wrote:
On Fri, 04 Jan 2013 13:14:54 -0000,

wrote:


Snip

Sorry I've been away so long!!

Your diagram is not going to happen.....ever!!

Primary power = 240 Vp times 1.5 Ip equals 360 Watts
Secondary power = 120 Vs times 3.0 Is equals 360 watts

Secondary power equals Primary power, so no (i.e. zero, zilch) power
can
be dissipated in the top half of the transformer, so zero voltage
developed across the top half of the transformer, so Vs must equal
Vp,
i.e. 240 V not the 120 V your diagram shows.

Not going to happen....ever!! Sorry!!

Daniel

It was simply a rough diagram to work out the approximate current
flow,
I was assuming no losses!


In my calculations I was assuming no losses, too, so it doesn't
work, in
any case.

Daniel

The diagram I drew at
http://petersphotos.com/temp/transformer.jpg makes
perfect sense to me.

If you create a secondary coil in the lower half and seperate the two
circuits, it's just like a normal transformer.


If.....If.....If

What you drew *Will not* work! No if's, no but's, no maybe's!!


Ok, please redraw my diagram showing me where you think the currents
travel.


Scott, I don't have great graphics skills, but:-

http://www.albury.net.au/~dxmm/transformer_mod.jpeg

If you joined the primary and secondary 0V wires, you are left with a
three contact transformer!!

Daniel