"gareth" wrote in message
...
"Jim Mueller" wrote in message
eb.com...
On Mon, 12 May 2014 12:08:00 +0100, gareth wrote:

If one could "ride the electron", what happens deep inside the
transformer such that the inductance of the primary does not limit the
current passing through that primary?

(This lack of understanding always made me feel uneasy when winding my
own potcores for the instrumentation amplifier I was charged with
desiging in my first year after graduating)

This, amongst other things, puzzled me for some time, but ultimately I
reasoned it out. Would anybody like to partake in a _GENTLEMANLY_
discussion about such technical matters?

Also, what of a visualisation of the Magnetic Vector Potential, "A"?

The inductance of the primary does limit the primary current (except for
losses) as long as the secondary is unloaded. When a load is placed on
the transformer, the current through the secondary generates it's own
magnetic field in opposition to the field from the primary. This
effectively reduces the inductance and allows more current to flow.

There are also other ways to look at it.

Yup, you've got it!


.... and, of course, when the secondary circuit is saturated, it is then that
the
inductance of the primary comes into play to limit the current. An almost
instantaneous effect but then, unless at RF, we do not consider wave
behaviour in transformers.