MH's ideal coil and voltage question

[tinman]

MH,

I believe the "opposite" current that Tinman is discussing is with reference to the induced voltage that creates opposing currents as per the definition of CEMF.  But again, I never read that to mean he believed the CEMF actually reversed the flow sufficiently to "charge the battery" so to speak.

As for the rest of what he is saying, well, that is why I suggested he consider looking into superconductors.

All conductors are inductors, and according to what he is saying, current could not flow through a length of superconducting wire (or at least no more than flows at T=0).  So we kinda' know that can't be right.

There is nothing wrong with leading a horse to water, but...

PW

PW
I have never said that there would be a current flow going back into the battery.
Here is what i said
Quote post 1390-->What you dont get,is that the reverse current flow is subtracted from the induced current flow,and you cannot separate the two,as one subtracts from the other,and all you see is the end resulting value.

MH came up with this !reversed!(self induced current) current flow going back into the battery/power supply,when he tried once again to make me look like a fool,in post 1372-->
So like if the 5th time constant current is 100 amps and the 1st time constant current is 25 amps then the reverse current produced by the CEMF is 75 amps.   So does that mean when you first apply the voltage across the coil the current is -75 amps?  It's "Attack from Planet Bizarro and the Pumpkin Patch Creatures."

This was his response when i stated that-Quote:The value of the current flow produce by the CEMF is less than that induced by the applied voltage. It you take the peak current value that will be flowing at the 5th time constant,and you subtract from that the peak current value of the first time constant,you are left with the calculated reverse current produced by the CEMF. As you  can see,the current produced by the CEMF ,is less than that of the induced current by the applied voltage.

So as you can see,MH plucked this !reverse current flow back into the battery! out from his own blunder on calculating what the current flow would be after 1 time constant,when the steady current flow value after the fifth time constant would have an end value of 100 amp's.

So now you see why these issues keep coming up,and a threads become 100's of pages long.

For me, there are only two outstanding issues and I will mention them again and I will put them in a better sequence this time:

1.  MH gets up the learning curve , and clearly demonstrates that he understands what he is doing.
2.  MH admits that he is wrong when he stated that my response to what CEMF is,how it creates a current that is in opposition to the induced current,and how it reacts against,or impedes upon the induced current,was incorrect.


Brad

[tinman]

Quick setup showing the EMF and CEMF in a DC motor in real time,as a load is applied.

https://www.youtube.com/watch?v=SqPur5JUumg


Brad

[tinman]

  Can't really tell from the video.  What interests me, is when the consumption goes to zero, and then negative.  I experience zeroing of the consumption often...as seen from the meter of my supply, when this happens, it means that my "self-induced voltage" is higher than the applied, but unlike in your demonstration, my machine does not continue to motor strong. 


 




Regards

Where you are saying "induced", the text books say "applied".  That being said, the comparison is applied versus self-induced EMF (CEMF), applied versus self-induced current.

Current is not applied to the motor,it is induced by the applied EMF.

This leads me to ask where the energy is coming from that keeps your rotor running strong even after the consumption has gone to zero, because technically it shouldn't be.

Technically you'd be correct

Regarding the inversion of the current, I would like to get into that, however, it would be best if you addressed my noted concerns, you aren't obligated to do so, I am just curious, and am probably one of the only ones who is really listening, to what you are saying and demonstrating "right now".

There are a few following this thread,so i dont think it will be missed lol.

During the video you state "as we increase the load on our motor...", you then adjust the pot.  One speculates that the CEMF labeled motor, is functioning as a "generator", the load across it being the pot.

Yes,that is the load motor-(CEMF) motor,but as the self induced current increases past the value of the EMF induced current,then it becomes the motor,and the(EMF) motor becomes the generator,and so the current reverses through the CVR

Nothing special happening there


Brad

[hoptoad]

Current is applied to the motor, self-induction opposes, via an induced EMF, the build up of the applied current.  In this wise, to say that it, the applied current, is "induced" by the applied EMF is inaccurate.  Can you demonstrate current being "induced" by the applied EMF, using your present demonstration platform?
What is this thing you are calling "EMF induced current"?
Regards

While the term used may appear confusing, it is correct. You don't get current until a voltage source (EMF) is applied to a load circuit.
So the voltage (EMF) is applied to the load circuit, and this application of the voltage (EMF) to the load circuit induces a current to flow in the load circuit. So yes, the applied current is actually an EMF induced current.

Personally I would call the EMF induced current an applied current or source current, but it's really a semantic issue, which should be clarified by the context of the use of the term.

However, your confusion highlights yet again how everyone needs to be on the same page with terminology.

induce : meaning
ɪnˈdjuːs/verb
1.
succeed in persuading or leading (someone) to do something.
"the pickets induced many workers to stay away"
synonyms:persuade, convince, prevail upon, get, make, prompt, move, inspire, instigate,influence, exert influence on, press, urge, incite, encourage, impel, actuate, motivate;
2.
bring about or give rise to.
"none of these measures induced a change of policy"
synonyms:bring about, bring on, cause, be the cause of, produce, effect, create, give rise to,generate, originate, instigate, engender, occasion, set in motion, develop, lead to,result in, have as a consequence, have as a result, trigger off, spark off, whip up, stir up, kindle, arouse, rouse, foster, promote, encourage;

Cheers

[MileHigh]

Brad:

How about just fixing this comment of yours:

<<< Yea--good one MH--only we do not have a loop,we have a coil attached to a voltage supply.  >>>

Can you do that?

MileHIgh