The Transformer
 

On Tue, 13 May 2014 12:36:54 +0100, Kafkaesque
wrote:
Are you referring to saturation of the diodes in the rectifier
connected
to the secondary?

To save energy put the diode in series with the primary.

--
73 de Frank Turner-Smith G3VKI - mine's a pint.

BRIAN !!!!! M3OSN !!!!!
 

"gareth" wrote in message
...
"Brian Reay" wrote in message
...

I've little doubt this is another of his attempts to start a vehicle for
his abuse.

39, OM.

Why are you so opposed to every attempt of mine to foment discussion
on technical matters in the amateur radio NG, and thereby restore to
prominence
the other great tradition of amateur radio, that of international
gentlemanliness?

What have you got against open technical discussion?

So far, the only abuse is that quoted above, and it has come from your own
keyboard, and your own keyboard alone.

What is it that has you contributing so much bile and bitterness into
these NG?

You repeatedly lay that sort of accusation at the door of other
contributors,
but invariably it is from you that unpleasantness originates, as quoted
above.


Are you there, Brian?

Hullo?

BRIAN !! M3OSN !!! ARE YOU THERE, OM?
 

"gareth" wrote in message
...
"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.


Brian?



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.


Brian?

(Put a stick transversely across the varying flow rates and the curl will
become
immediately apparent to you)


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.


Brian?




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.



Brian?



To paraphrase your own remark, I find it to be unbelievable that someone
who boasts of two degrees, the first in electronics and the second in
mathematics, could be so ignorant of such matters; matters that prelie an
understanding of Maxwell's Equations. In my time, we studied grad, div
and curl and all the associated identities in the second year maths course.

BRIAN !! M3OSN !!! ARE YOU THERE, OM?
 

I think that M3OSN's habit of running away from technical discussion,
shouting
insults as he goes, tells us all we need to know about his persona when he
pours scorn on others' technical viewpoints; his persona is one of an
ignorant blustering infant desperate for the adulation of his peers.

Which gives us number 46 in M3OSN's repertoire of standard responses ...

46. Ignorant blustering infant desperate for attention

"gareth" wrote in message
...
"gareth" wrote in message
...
"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.


Brian?



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.


Brian?

(Put a stick transversely across the varying flow rates and the curl will
become
immediately apparent to you)


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.


Brian?




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.



Brian?



To paraphrase your own remark, I find it to be unbelievable that someone
who boasts of two degrees, the first in electronics and the second in
mathematics, could be so ignorant of such matters; matters that prelie an
understanding of Maxwell's Equations. In my time, we studied grad, div
and curl and all the associated identities in the second year maths
course.

BRIAN !!!!! M3OSN !!!!!
 

On Wed, 14 May 2014 16:04:26 +0100, gareth wrote:

Hullo?

I come to this quiet corner of the internets to see what's brewing. It is
very peaceful as I am often the only person here, AFAIK.

Unfortunately someone seems to have included this group when posting to
ukra and then all the sheep automatically follow. Pointless really if
there's me in here and I don't want to see all the usual dross posted on
ukra - that's why I unsubscribed.

Can we please not have ukra in rrah, TIA & 88s.



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

The Transformer
 

On 13/05/2014 12:23, gareth wrote:
"Brian Morrison" wrote in message
...

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

When the core is saturated the effective inductance is zero. Think
about the B-H loop diagram for a transformer.

You misunderstand.

I was referring to the saturation of the current, which is limited by the
secondary load.

I think I understand your confusion Gareth.

If the core of the transformer is saturating, then the secondary output
will be distorted, and the peak voltage will not be as high as one might
expect from the turns ratio.

This in turn will limit the secondary current for any given load.

Could this be the effect that you have mistakenly assumed to be
"saturation of the current"?

73
Mike G4KFK

BRIAN !!!!! M3OSN !!!!!
 

"Wymsey" wrote in message
...
On Wed, 14 May 2014 16:04:26 +0100, gareth wrote:

Hullo?

I come to this quiet corner of the internets to see what's brewing. It is
very peaceful as I am often the only person here, AFAIK.


I know different.

The Transformer
 

On 13/05/2014 17:25, Rambo wrote:

That's an interesting point Gareth, why exactly would some-one who had
such a successful career, take up teaching?

It is not uncommon for people with a successful career to look towards
teaching. I was facing redundancy this year and my plan if accepted for
VR was to go into teacher training. After 30 years + in engineering I
was looking at teaching physics or maths.
As it happened I was turned down for voluntary redundancy so I am still
in industry.

Andy

The Transformer
 

In message , gareth
writes
"Brian Morrison" wrote in message
k...

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

When the core is saturated the effective inductance is zero. Think
about the B-H loop diagram for a transformer.

You misunderstand.

I was referring to the saturation of the current, which is limited by the
secondary load.

It's the core which saturates. It can start to saturate without any
secondary current being drawn. If the transformer 'runs out of'
inductance, the primary current can go sky high, as it is essentially
limited by the primary resistance.
--
Ian

The Transformer
 

"Ian Jackson" wrote in message
...
In message , gareth
writes
"Brian Morrison" wrote in message
. uk...

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

When the core is saturated the effective inductance is zero. Think
about the B-H loop diagram for a transformer.

You misunderstand.

I was referring to the saturation of the current, which is limited by the
secondary load.

It's the core which saturates. It can start to saturate without any
secondary current being drawn. If the transformer 'runs out of'
inductance, the primary current can go sky high, as it is essentially
limited by the primary resistance.

You are discussing magnetic saturation. I was discussing the current
saturating to the limit brought on by the secondary load.

Although the I=E/R relationship is normally presented as instantaneous,
it is not, and it takes a finite, although in finitesimal, time to reach the
value.

Likewise, in my comments, it takes some small time for the secondary current
to
reach that value, to saturate, in other words.

Consider a simple circuit of battery, switch and resistor; how does the
battery "know" how much current to flow before it has "encountered" the
resistor?

Perhaps a poor choice of wording on my behalf, when I did not
anticipate your "susceptance"? :-)

But this is (hopefully!) a gentlemanly chatty group and chatting on civilly
should always iron out such misunderstandings.