# sensorless vector



## JRaef (Mar 23, 2009)

Given your location and the possible notorious use you could make of drive applications, I for one am not willing to help. Sorry, that's just the way it is.


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## eric7379 (Jan 5, 2010)

JRaef said:


> Given your location and the possible notorious use you could make of drive applications, I for one am not willing to help. Sorry, that's just the way it is.


While I applaud you for taking this stance, JRaef, you didn't seem to mind helping him at all in the thread about switching out a DC motor with an AC motor. 


I, for one, am taking the same approach. No assistance from me at all.


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## John (Jan 22, 2007)

Sometimes misinformation is better than no information.


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## JRaef (Mar 23, 2009)

eric7379 said:


> While I applaud you for taking this stance, JRaef, you didn't seem to mind helping him at all in the thread about switching out a DC motor with an AC motor.
> 
> 
> I, for one, am taking the same approach. No assistance from me at all.


I must not have noticed his location before.


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## John Valdes (May 17, 2007)

seee said:


> hello.
> 
> how much is speed range of sensorless vector drive?(1/100 or etc)
> I know the speed range of most vfds scalar control are 1/5 that means if i use for example a 3000rpm motor it can not deliver enough torque at speeds below 600 rmp.
> ...


Lets not answer yes or no as we cannot make a call without knowing more.
First you must understand what the motor manufacturer calls the motor speed ratio. Or whats called the "turn down ratio". This is the lowest speed the motor is recommended to be run verses the nameplate RPM.
Some VFD's are capable of very high torque at very slow speeds. Some applications require a feedback device for torque and other considerations.
Look in any motor catalog and you will see the "turn down ratio". This value indicates how slow you can run the motor, without overheating it.
The addition of drives, gearing and external cooling will effect the ratio.
Is that what you are asking?


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## dronai (Apr 11, 2011)

The OP had listed Brazil as his location before. I Pm'd him to ask where in Brazil he is located, because we go down there a lot. He then said he wrote that by mistake, and changed it. Maybe he's legit ?

But.. Anyone can come in here with any false location, and receive valuable, or sensitive information


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## John Valdes (May 17, 2007)

dronai said:


> The OP had listed Brazil as his location before. I Pm'd him to ask where in Brazil he is located, because we go down there a lot. He then said he wrote that by mistake, and changed it. Maybe he's legit ?
> But.. Anyone can come in here with any false location, and receive valuable, or sensitive information


Thanks for the heads up Dorian. Unlike the others I have no problem helping anyone from anywhere.
Now, I am certain he is not trying to find out about centrifuges as he asked about slowing down a motor and not speeding one up. :laughing: 

If he has provided two locations that far apart and both so very much different he must be a troll.
So, Seee. Tell us who you really are and where you reside. Without reassurance, I for one will forgo any further attempts at helping you.
I have nothing against all Iraqis. I do have problems with people not being truthful.


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## eric7379 (Jan 5, 2010)

John Valdes said:


> Thanks for the heads up Dorian. Unlike the others I have no problem helping anyone from anywhere.
> Now, I am certain he is not trying to find out about centrifuges as he asked about slowing down a motor and not speeding one up. :laughing:
> 
> If he has provided two locations that far apart and both so very much different he must be a troll.
> ...


 
Did you even bother to read where the guy says he is from now, John??? Before you go placing yourself on a pedestal, you might want to double-check his location. He said *Iran*, not Iraq. Big difference, in my book.

Say whatever you want to John if it makes you feel like a better person. I will not offer any assistance to anyone that says that they are from Iran. Not that they are Iranian, but that they are currently in Iran.


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## Wirenuting (Sep 12, 2010)

eric7379 said:


> Did you even bother to read where the guy says he is from now, John??? Before you go placing yourself on a pedestal, you might want to double-check his location. He said Iran, not Iraq. Big difference, in my book.
> 
> Say whatever you want to John if it makes you feel like a better person. I will not offer any assistance to anyone that says that they are from Iran. Not that they are Iranian, but that they are currently in Iran.


How about we help him.
A little to fast, a little to quick on a stop,, ect.. 
Then maybe we can see if something flys apart on the 6 o'clock news. 

I really don't believe that they are that stupid to come here and ask questions. They are pretty sharp in their engineering. 
If they came here I'm sure they would list themselves as being from NJ, or some other exotic place. 
But it is nice to see that some people care enough to not share. I like that. 
Years ago people laughed at the Russians and said their equipment was junk. They even still used vacuum tubes in their fighters. Turns out them planes would keep flying after an EMP.


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## John Valdes (May 17, 2007)

eric7379 said:


> Did you even bother to read where the guy says he is from now, John??? Before you go placing yourself on a pedestal, you might want to double-check his location. He said *Iran*, not Iraq. Big difference, in my book.
> 
> Say whatever you want to John if it makes you feel like a better person. I will not offer any assistance to anyone that says that they are from Iran. Not that they are Iranian, but that they are currently in Iran.


I saw he was from Iran. Pedestal? I just said I would help anyone from any country. Iran is no different.
Better person? I am no better than anyone else. 
Why is it wrong to help someone from Iran? Maybe he works in a factory like many people do here. 
Do you dislike the OP because of where he is or where he is from? I don't dislike him and will continue to help him as long as he is a forum member.
Take it up with the moderators if you feel he should not be here. 
They allowed him to open an account, not me.


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## MDShunk (Jan 7, 2007)

I stayed in the same hotel as the minister of the water works for the city of Matsule (sp?) in Iran for a week. Ate breakfast with him most mornings in the hotel restaurant. We didn't talk about motors and drives, though. :laughing: He mostly wanted to talk about how beautiful the country and the Black Sea was. Pretty nice guy. Was traveling with some US woman for some reason. I never really asked. She seemed like some kind of secretary or something.


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## Del (Feb 10, 2011)

Sensor less Flux vector VFDs, have a speed range of zero to 100% depending on frequency i.e location in the world.
I once worked on a bakery where seven sensorless flux vextor drives on conveyors were syncronised based off a common reference encoder at the head end- essentially creating a virtual camshaft.
It was a swine to set up.


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## MDShunk (Jan 7, 2007)

Del said:


> Sensor less Flux vector VFDs, have a speed range of zero to 100% depending on frequency i.e location in the world.
> I once worked on a bakery where seven sensorless flux vextor drives on conveyors were syncronised based off a common reference encoder at the head end- essentially creating a virtual camshaft.
> It was a swine to set up.


I never really liked that idea for a conveyor system. If it's something sensitive to tipping at transfers, like bottles, there are better ways. For other items, it's not that critical, and you often want certain conveyors to run faster or slower to pull a gap or build surge for a variety of reasons.


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## eric7379 (Jan 5, 2010)

John Valdes said:


> I saw he was from Iran. Pedestal? I just said I would help anyone from any country. Iran is no different.
> Better person? I am no better than anyone else.
> Why is it wrong to help someone from Iran? Maybe he works in a factory like many people do here.
> Do you dislike the OP because of where he is or where he is from? I don't dislike him and will continue to help him as long as he is a forum member.
> ...


I have nothing against Iranians. I have known several throughout the years. Was pretty good friends with one, actually.

What I do have a problem with is the location. If the OP says that they are in Iran, then I flat out refuse to be of any assistance whatsoever. Maybe he works for the Iranian government and is trying to befriend a naive American into helping him understand some electrical issues that they are having with some equipment that is used to manufacture weaponry that is ultimately used to kill Americans. Who knows. The fact is that neither one of us knows what the OP's exact situation is, and frankly, I don't care to know at this point. 

What I do know is that it would be extremely easy for someone from Iran to come on here using a false location. The OP first said Brazil, and now he says Iran?? Something ain't right. Probably just a troll. Probably got the idea from Cletis or Peter D, but I am not taking that chance. If you want to help him, go right ahead.


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## etb (Sep 8, 2010)

dronai said:


> The OP had listed Brazil as his location before. I Pm'd him to ask where in Brazil he is located, because we go down there a lot. He then said he wrote that by mistake, and changed it. Maybe he's legit ?


I'm sure one can type "Brazil" by mistake....


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## John Valdes (May 17, 2007)

etb said:


> I'm sure one can type "Brazil" by mistake....


I can understand why one would try and hide the fact they are from Iran.


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## JRaef (Mar 23, 2009)

I have a good friend from that part of the world, he and his entire family refer to themselves as "Persian" after moving out of the country when the Arab Muslims took over with the fall of the Shaw (he is Zoroastrian, not Muslim, which was the dominant religion before the Arabs took over centuries ago). They want no connection to the lunatics running that country. 

He is an EE and is very capable, but he will be the first to admit that he had to go to Germany to get his education, because academics are looked down upon by the Theocracy running Iran. His mother stayed behind and he is allowed to go visit, he says they are very very backward there, that almost all technology in use is in some way connected to the military. But because of all of the sanctions, most of what they get is either used junk or black market stuff and they get no support from anyone. 

Hence, I chose to not knowingly participate in circumventing the only pressure that the rest of the civilized world choses to allow to be used against them; denial of technological support. If they want to participate in the civilized modern world, reject the theocratic lunatics that currently run that country. I know they have tried and failed a couple of times already, so did we when we wanted to split off from an English lunatocracy. You just have to keep it up until you succeed.


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