On Tue, 24 Jun 2008 11:17:36 -0700 (PDT), dlzc <dlzc1@[EMAIL PROTECTED]
> wrote:
>Dear John C. Polasek:
>
>On Jun 19, 5:19 pm, John C. Polasek <jpola...@[EMAIL PROTECTED]
> wrote:
>> On Thu, 19 Jun 2008 14:18:52 -0700 (PDT),dlzc<dl...@[EMAIL PROTECTED]
> wrote:
>> >Dear John C. Polasek:
>>
>> >On Jun 19, 1:34 pm, John C. Polasek <jpola...@[EMAIL PROTECTED]
> wrote:
>> >> On Thu, 19 Jun 2008 07:30:59 -0700 (PDT),dlzc<dl...@[EMAIL PROTECTED]
> wrote:
>> >> >On Jun 19, 6:48 am, John C. Polasek <jpola...@[EMAIL PROTECTED]
> wrote:
>> >...
>> >> >> What this means is that the bound electrons
>> >> >> are on very weak "springs" and have large
>> >> >> deflections (K = 80) so that a moderate field might
>> >> >> break the springs and free the electron for
>> >> >> conduction.
>>
>> >> >No. You are conflating conduction or conductivity
>> >> >with permittivity. In conduction (your "breakdown"),
>> >> >electrons / ions are free to migrate through the
>> >> >material the electric field is applied to. In
>> >> >permittivity, the material undergos a "physical"
>> >> >change NOT requiring the motion of loose charges.
>>
>> >> You seem unable to read a sentence: I am saying
>> >> you have permittivity as long as the electrons
>> >> remain elastically bound, (and thus able to
>> >> store energy) but upon their breaking loose you
>> >> have the ohmic condition.
>>
>> >I can read a sentence. You veered off from
>> >permittivity to discussing breakdown. This is
>> >not what the OP asked about.
>>
>> To the contrary, the OP asked asked this in
>> his original note: "Is there any relation between
>> dielectric constant and dielectric strength?"
>
>I stand corrected.
>
>> Again, failure to read.
>
>Ahem...
>
>> And again I reiterate that high K means large
>> deflections with moderate fields such that
>> avalanching is possible as the bonds exceed
>> their elastic limit. That's how all breakdown occurs.
>
>But high K does not correlate with a low breakdown voltage.
>
>> >Additionally, the Rube Goldberg device you
>> >construct, relating high k value (loose springs)
>> >to low dielectric breakdown voltage does not
>> >pan out.
>>
>> I see you didn't consult my paper and I
>> consider it churlish of you to cut out reference
>> to it as the Permittivity paper at
>http://www.dualspace.net.
>> Even a cursory examination will make it clear
>> that my model far outcl***** your frozen
>> chicken hypothesis.
>
>Everyone has their opinion. And it was not an hypothesis, it was a
>simile.
>
>...
>> In any case, it's moot, all this talk of physical
>> chemistry and bonds, because the last
>> dielectric anyone would suggest would be
>> WATER! Water? Are you kidding?
>
>I intentionally dropped an operating electric hand drill into a pool
>of 18 meg ohm water. I then reached in and pulled the operating drill
>out with my bare hand. No shock.
>
>Additionally, some of the most used level detectors, use only water's
>k value. "capacitive proximity detector" or "capacitive level switch"
>
>Your personal experience limits your "common sense".
>
>> >> Please explain, preferably without the assistsance
>> >> of poultry.
>>
>> >In general, the water molecules (in this case) do not
>> >get closer together, they simply orient themsleves
>> >with the oxygen atoms facing the anode. The
>> >analogy you ceased to be humored by used
>> >gravitation in place of an applied E field. In a
>> >material, alignment of charges yields energy...
>> >like the "latent heat of fusion" of a salt, for
>> >example.
>>
>> Yes, polarization stores energy and can also
>> release it, given a closed circuit.
>
>No poultry.
>
>...
>> >> >> What is "thinly insulated"?
>>
>> >> >For a capacitive cell, with a dielectric thickness
>> >> >t_d, and "thin insulator" thickness t_i:
>> >> >2 * t_i << t_d
>>
>> That blows away my conception of ideal geometry
>> because, Wait, wait, I think you're trying to tell
>> me the dielectric needs 2 miniscule physical
>> separators to prevent the dielectric from touching
>> the electrodes. Would you mind amplifying on
>> that one?
>
>The intent is to have a net charge on each plate, just for "conceptual
>purity".
>
>> >So at least in your opinion I answered that one...
>>
>> No it just raised the last question; does it need
>> 2 empty spacers?
>
>For the "mathematics", imagine that the anode is not insulated. Now
>you will have one plate with a low positive charge and a high negative
>charge. The dynamics changes, is all. Just a little weird to
>consider.
>
>> I would like to learn more about this "thin insulator"
>> concept. Do you have a reference text that
>> introduces it? It's not in Smyth or Panofsky.
>
>No, it is most likely either a pedantic device, or something that
>sensor manufacturer's depend on to protect the conductors of their
>electrodes. More than likely, the self-healing oxide layer of the
>conductor when only low currents are applied.
>
>The intent is to get at the field in the dielectric(s), and ignore the
>ions which are not of concern (but can cause physical problems).
>
>David A. Smith
Thank you. I recall a liquid level in the A1BNC system which was part
of a bridge at 400hz.
In any real capacitor the function of the plates is to contact every
bit of the dielectric surface, simply as a means of polarizing the
dielectric. An insulating film to protect against corrosion makes
sense but is in no way a factor in the capacitors fundtion.
In that case it should be included in the dielectric stack where
because of its near-micron thickness it could be ignored.
Electrolytic capacitors have high capacity this way: the dielectric is
chemically produced. Wiki says the aluminum oxide can withstand 1e9
V/m which means in a 100 V capacitor the film would be 1/10 micron!
John Polasek
|
