Author Topic: Motor BEMF  (Read 54300 times)

Offline cadstarsucks

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Re: Motor BEMF
« Reply #15 on: September 02, 2007, 07:14:20 PM »
Confrontational again. That is your error.
how are facts confrontational?

Dan

Offline myelectricbike

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Re: Motor BEMF
« Reply #16 on: September 02, 2007, 07:54:43 PM »
I'm waiting for the fact part. The rest is confrontational.

Offline Dave

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Re: Motor BEMF
« Reply #17 on: September 02, 2007, 08:16:16 PM »
Sorry you feel that way Dave, but I was here long before you which makes you the troll, now doesn't it? :(

No. Where is it written that longevity excludes one from making an ass or nuisance of himself?

Offline myelectricbike

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Re: Motor BEMF
« Reply #18 on: September 02, 2007, 08:19:00 PM »
Its the other way around Dave. You come to a party and pick a fight with someone who is already there tending to whatever task they have found available or were assigned, then you are the trouble maker and not the other way around. You do not go to the Auto Tag Department and try to break in line. Its a no, no.
« Last Edit: September 02, 2007, 08:21:31 PM by myelectricbike »

Offline cadstarsucks

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Re: Motor BEMF
« Reply #19 on: September 02, 2007, 08:20:24 PM »
I'm waiting for the fact part. The rest is confrontational.
And how is ignoring the facts in a post not?  I'll repeat them shall I?

V=IR, it does not matter if it is the internal RESISTANCE of a battery or a motor.

Therefore if the speed of the HBS-36 motor drops from 308RPM to 216RPM we get that it's internal resistance is (36V (the curve test voltage) x (1-216RPM/308RPM)) (the voltage across internal resistance) / 20.5A (the full load test current) = 0.5 ohms

As a proof you go back the other way - P=I²R ...  20.5A²0.5=210W which coincidentally is just about the difference between the curve input power of 730W minus the curve output power of 509W.

Offline cadstarsucks

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Re: Motor BEMF
« Reply #20 on: September 02, 2007, 08:22:48 PM »
Its the other way around Dave. You come to a party and pick a fight with someone who is already there tending to whatever task they have found available or were assigned, then you are the trouble maker and not the other way around. You do not go to the Auto Tag Department and try to break in line. Its a no, no.
That is not true...the trouble maker is the one who picks the fight no matter which one was there first.

Offline myelectricbike

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Re: Motor BEMF
« Reply #21 on: September 02, 2007, 08:32:34 PM »
Its the other way around Dave. You come to a party and pick a fight with someone who is already there tending to whatever task they have found available or were assigned, then you are the trouble maker and not the other way around. You do not go to the Auto Tag Department and try to break in line. Its a no, no.
That is not true...the trouble maker is the one who picks the fight no matter which one was there first.

In that light then I did not pick the fight. What's more...



V=IR, it does not matter if it is the internal RESISTANCE of a battery or a motor.


If this is true then what is your point? I've not stated otherwise although I might disagree.

Quote
Therefore if the speed of the HBS-36 motor drops from 308RPM to 216RPM we get that it's internal resistance is (36V (the curve test voltage) x (1-216RPM/308RPM)) (the voltage across internal resistance) / 20.5A (the full load test current) = 0.5 ohms

As a proof you go back the other way - P=I²R ...  20.5A²0.5=210W which coincidentally is just about the difference between the curve input power of 730W minus the curve output power of 509W.


You have made the assumption that 1.) the above is fact and 2.) that I dispute it. One does not beget the other without becoming a logical fallacy. However, you have ignored this and proceeded to be confrontational anyway.

Am I to conclude then that your purpose for being here is to be controversial and nothing else?

Let me guess.

Offline Dave

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Re: Motor BEMF
« Reply #22 on: September 02, 2007, 08:33:51 PM »
Its the other way around Dave. You come to a party and pick a fight with someone who is already there tending to whatever task they have found available or were assigned, then you are the trouble maker and not the other way around. You do not go to the Auto Tag Department and try to break in line. Its a no, no.
That is not true...the trouble maker is the one who picks the fight no matter which one was there first.

Exactly. I didn't come here to pick a fight, nor am I the one who picked this fight. Seems that whenever there is an argument or confrontation Patrick is in the thick of it. No coincidence that.

I suggest we ignore him. For normal people, that's enough to make them go away, but unfortunately he thinks he owns the place so I doubt he will. Doesn't hurt to hope though.

Offline myelectricbike

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Re: Motor BEMF
« Reply #23 on: September 02, 2007, 08:35:21 PM »
I suggest you find someone else to pick on as well.

On second thought while you are picking on me maybe I can keep you busy enough where you are not picking on someone else.
« Last Edit: September 02, 2007, 08:50:21 PM by myelectricbike »

Offline cadstarsucks

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Re: Motor BEMF
« Reply #24 on: September 02, 2007, 08:51:00 PM »
I suggest you find someone else to pick on as well.
Pick on you?  That's amusing.  I only try to teach and help.  You have misunderstandings that you propagate as fact and then have the nerve to be offended when someone knowledgeable comes in and points out the truth of the matter.

Son, had I wanted to pick on you, you would have crawled under a rock crying for mommy.  You are way out of your league.

You never did answer as to what your degree was, you only made some mention of a college physics course.  Shall we then assume you are a college drop out?  And how, pray tell, does that qualify you to make any claims at all?

Offline cadstarsucks

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Re: Motor BEMF
« Reply #25 on: September 02, 2007, 08:53:28 PM »
Exactly. I didn't come here to pick a fight, nor am I the one who picked this fight. Seems that whenever there is an argument or confrontation Patrick is in the thick of it. No coincidence that.

I suggest we ignore him. For normal people, that's enough to make them go away, but unfortunately he thinks he owns the place so I doubt he will. Doesn't hurt to hope though.
True but then he gets to do more damage to those who come to try and learn.

Dan

Offline myelectricbike

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Re: Motor BEMF
« Reply #26 on: September 02, 2007, 09:04:31 PM »
Why do you keep double posting?

Aside from that, even Dave says that you taught him nothing...

How about a layman's explanation of BEMF? I have a good electronics foundation -- Air Force trained for communications maintenance -- but a lot of this theoretical stuff goes right over my head.

Also, if someone (you?!) came up with a good design for the ideal controller and made it open source, couldn't hobbyists like ourselves buy the components and put it together ourselves? Making PCB's isn't that difficult; after that comes the soldering, which is far from rocket science... The thing that is needed is a good design to start from.



However, I am learning what the risk might be were I not here to keep you busy until I find a more militant, combative type who might enjoy taking my place. And don't kid yourself bro, your league is way to low for me.

Offline Dave

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Re: Motor BEMF
« Reply #27 on: September 02, 2007, 09:17:02 PM »
Aside from that, even Dave says that you taught him nothing...


I thought I told you to speak for yourself.

And don't kid yourself bro, your league is way to low for me.

Guess that's why you keep your contact info to the bare minimum on this board. Afraid of pissing someone off and having them track you down. Note that both Dan and I have a bit more info attached to our profiles on this forum. You on the other hand have nothing, and you still spam others in a vain attempt to sell something. As if I would buy something from someone I know nothing about and is not forthcoming with anything more than a verizon.net email address.

I suggest we take this offline. Check your private messages. Or drop me a line by email.

Offline myelectricbike

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Re: Motor BEMF
« Reply #28 on: September 02, 2007, 09:27:23 PM »
Sorry, Dave you had your chance with offline communication and then came online and made essentially the same comment in regard to my private contact, making it public for everyone else to read from your twisted and erroneous point of view. You are the one who has proven themselves not to be trustworthy Dave, rather than I. And yes, I've been on the Internet since the early 90's and know well enough to avoid providing personal information to such persons as yourself who have demonstrated or expressed malicious intent that I might run into online.

Offline cadstarsucks

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Re: Motor BEMF
« Reply #29 on: September 02, 2007, 09:42:47 PM »
Quote
Therefore if the speed of the HBS-36 motor drops from 308RPM to 216RPM we get that it's internal resistance is (36V (the curve test voltage) x (1-216RPM/308RPM)) (the voltage across internal resistance) / 20.5A (the full load test current) = 0.5 ohms

As a proof you go back the other way - P=I²R ...  20.5A²0.5=210W which coincidentally is just about the difference between the curve input power of 730W minus the curve output power of 509W.


You have made the assumption that 1.) the above is fact and 2.) that I dispute it. One does not beget the other without becoming a logical fallacy. However, you have ignored this and proceeded to be confrontational anyway.

Am I to conclude then that your purpose for being here is to be controversial and nothing else?

Let me guess.
Interesting...I missed this one. 

Actually it IS fact, direct from rudimentary electronics and the performance curve on the Golden site.

Your statements that, in effect, all power supplied to the motor heats it up does indeed dispute it.