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"?

"gareth" wrote in message
...
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"?

Come on then Gareth, we know you are just dying to tell us all the answers.

"gareth" wrote in message
...
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"?



PASS .......

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.

--
Jim Mueller

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.

"gareth" wrote in message
...
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"?

Stop trying to look intelligent, Beanie, it doesn't work.
--
;-)
..
73 de Frank Turner-Smith G3VKI - mine's a pint.
..
http://turner-smith.co.uk

"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!

On Mon, 12 May 2014 13:04:26 +0100, Badluck Jimbo ... wrote:

PASS .......

With honours!



--
M0WYM
Sales @ radiowymsey
http://stores.ebay.co.uk/Sales-At-Radio-Wymsey/

"Brian Reay" wrote in message
...

Another name for the Magnetic Vector Potential is curl,

That's not correct. Curl is a vector field function applicable to many
things, and you have to have the curl of something.

which is key to understanding it, as there is also a Magnetic Scalar
potential. Confuse the two and you will never understand them.

39


Back the Magnetic Vector Potential under the name of curl. Curl is used in
3D Vector Calculus (essentially calculus applied to the three orthogonal
components of a vector) and is referred to as a vector operator.
Importantly, it is only applied to rotating vectors

That is very misleading. The flow in a stream has curl when the
middle of the stream flows faster than the edges, but the individual
flow vectors are linear and not rotating.


and, like like all calculus, assumes infinitesimally small changes (in
this case rotation). The curl is found by applying the curl operator, and
it yields a vector represents the instantaneous direction and rate of
change of the Magnetic field.

That is misleading as well. A linear magnetic field moving through
a medium of varying permeability will have a spatial rate of change but
it will not be revealed by curling.


Thus, the Magnetic Vector Potential is a vector which represents the
instantaneous rate of change in the magnetic field.

That is complete nonsense. "Instantaneous" refers to a time element,
whereas curl is a spatial operator.


It is a vector as it has "direction" (as magnetic fields have directions)
and magnitude. It is a rate of change as the curl operator is a
differential operator, applied to the 3 components of rotating vector.


Note: In this context, the rotating vector may be generated by a
sinusoidal current in a coil as identical to one generated by a true
rotating magnetic field


No doubt the OP will criticise the above but that is up to him. It should
have been covered in a telecomms degree. The calculus, although in 3D, is
actually minimal, in that it is applied independently and so is really A
level (or O level for us oldies).


39

Quite a lot of blustering there, OM, but my question related to a visual
representation of the phenomen. Perhaps your much-noted need to
jump in with snide remarks over-rode your technical research via google?

"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.

On 13/05/2014 10:08, gareth wrote:

... and, of course, when the secondary circuit is saturated, it is then that

It's the core that saturates, not the secondary circuit.

the
inductance of the primary comes into play to limit the

It's the DC resistance that limits the primary current once the core is
saturated, not the inductance.