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

Lieutenant Scott wrote:
On Tue, 11 Dec 2012 13:18:22 -0000,
wrote:

Lieutenant Scott wrote:
On Mon, 10 Dec 2012 14:18:53 -0000,
wrote:

Lieutenant Scott wrote:


Snip



Not possible, Scotty, you cannot have both Primary and Secondary
currents flowing in one part of the (primary & Secondary) winding and
just Primary current flowing in the remainder of the (primary)
winding.

Cannot happen!!

As for the phase relationships between totally separated Primary and
Secondary windings, this can depend on the load connected to the
Secondary (i.e. is the load purely resistive or capacitively
reactive or
inductively reactive. And the phase relationship would also depend if
the "top" or the "bottom" of the Secondary is connected to the
bottom of
the Primary winding!!

I know, because one cancels the other out, it's more like the magnetic
force pushing against the existing current and reducing it. But
you can
think of it as adding and subtracting currents.

Forget a transformer.....think of two series resistors with a centre
take-off point, say a nine ohm resistor and a one ohm resistor
with ten
volts applied across the combination. One amp of current would be
flowing through the two resistors, with nine volts developed
across the
nine ohm resister and one volt across the one ohm resistor.

Now, if you connect another resistor across the one ohm resistor, you
don't get an increase of current flowing through the one ohm
resistor to
provide the current that would flow through the additional resistor.

I find that more confusing - as a transformer is actually creating the
voltage on the output.


"a transformer is actually creating the voltage on the output" in
exactly the same way as, in your impractical transformer, the primary
current flowing through the "secondary" winding creates the secondary
current .......... *ain't going to happen!!*

Daniel

http://petersphotos.com/temp/transformer.jpg

Correct so far?

Where I've written "?A", it has to add up to 1.5A upwards, otherwise
you'd be getting current from nowhere - 3 amps has to come out of the
centre tap.

I see this as the 1.5A flowing down (round the source circuit), plus the
3A flowing up round the load circuit. 1.5 down plus 3 up = 1.5 up.

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