# Why???



## Georgia Tech (Dec 5, 2008)

Too many Warp lovers trying to keep the peace


----------



## esoneson (Sep 1, 2008)

Georgia Tech said:


> I was reading in a thread where warp was providing some REALLY bogus data on their motors...I seem to experiance the same thing reading their charts and graphs as well...what gives??



What bogus data? Please be specific. Curious minds want to know what you are talking about. What, exactly is incorrect, misrepresented or mis-stated? Again, please be specific.

Eric


----------



## Stunt Driver (May 14, 2009)

Using a forklift motor myself, can't complain. Seems like timing - would be the ONLY difference, and that is user adjustable.

But, forklift is alot of messy work. Rich folks can afford shiny Warp


----------



## Tesseract (Sep 27, 2008)

Georgia Tech said:


> I was reading in a thread where warp was providing some REALLY bogus data on their motors...


I'd say NetGain's numbers are overstated, yes, but they aren't anywhere near as bad as the [exaggerations] like the claimed specs are for [other stuff]*. Your outrage here, to put it bluntly, is misplaced.




Georgia Tech said:


> why not use a GE 11 inch forklift? you can get these for around 200 bucks and i sware they are that SAME as an 11 inch motor!! I just don't understand


Sure, sure... maybe NOW you can get a GE 11" forklift motor for $200, but from late 2007 through mid '08 you couldn't even find a used forklift motor in this area, much less for $200. And guess what, once gas goes north of $3.00/gal. again you'll see forklift motors shoot back up in price before becoming as scarce as the hottest toy on Christmas Eve. 

Furthermore, you post questions here all the time asking for more info on random motors you find on ebay, etc.... Have you ever tried asking GE for tech support on one of their forklift motors? Yeah, good luck with that.

And does your most excellent advice apply to conversion shops? One of our clients estimates needing 50 Soliton1 controllers per year and another projects needing 100. You think they should go scouring equipment auctions, junkyards, etc., to find busted electric forklifts to then strip out the used and well-abused motor? And what do you think the owner of a converted Porsche 911 would say if he found some ratty old forklift motor under the lid?

What I'm basically saying is that what might make economic sense on the individual level does not necessarily translate well beyond that scale.

NetGain is one of the only companies willing to supply the EV community with a quality motor - do you think that the EV community would be better off if they went out of business?

Being frugal is one thing, being cheap to the point of stupidity is quite another.


----------



## Stunt Driver (May 14, 2009)

> What I'm basically saying is that what might make economic sense on the individual level does not necessarily translate well beyond that scale.


that is correctly said. 1-off convertion, with lots of mess and adopting. Wouldn't go there is I had extra $2k.


----------



## Georgia Tech (Dec 5, 2008)

Tesseract,

For startes 43.7 Hp at 72 volts at 453 amps what does that sound like to you? Sounds like Humbug to me..and for you to Hurl insults at me is unexcusable!! What Netgain giving you a commision or something? DAMN! tone yo Jets fool!

Yes I ask question on this forum thats how we learn I answer as much as I ask Buddy. If this little comunity does not stick together it will DIE! what are we now as big and bad as the Classic Hot Rod V-8 community? We have to ask questions and recruit new people thats how this movment keeps going!, if there is ANYTHING what so EVER that I learned I will ALWAYS share it! 




Tesseract said:


> And does your most excellent advice apply to conversion shops? One of our clients estimates needing 50 Soliton1 controllers per year and another projects needing 100. You think they should go scouring equipment auctions, junkyards, etc., to find busted electric forklifts to then strip out the used and well-abused motor? And what do you think the owner of a converted Porsche 911 would say if he found some ratty old forklift motor under the lid?


blah Blah Blah Blah...Ahhhh So what!.. Listen...Craftsmanship is Craftsmansship...You can spend thousands on brand new stuff (bolck heads carb Cam what ever ect..) but if you don't know what your doing and have crap technical skills it don't make no differance...When I use to hotrod mustangs you know where most of the money was spent? in the MACHINE SHOP!!! 
Point is good craftsmenship like a good motor house can take a 150 dollar motor form a forklift and turn it into something WAY better than a freakin warp motor...If you want to go with a Create motor like Warp then fine, but the longest thread on this ENTIRE forum is devoted to useing a froklift motor its that long for a REASON!!! Use a Create motor (warp) if you want to..

lets end this sheeet...before it gets started...


----------



## esoneson (Sep 1, 2008)

Georgia, slow down........take a deep breath. Obviously something has you very upset to trigger such a response. I, for one, will look past the tone of your posting and re-direct your attention to my post above (that, so far you have ignored).

"What bogus data? Please be specific. Curious minds want to know what you are talking about. What, exactly is incorrect, misrepresented or mis-stated? Again, please be specific."

Just to remind you of your own words "what so EVER that I learned I will ALWAYS share it! "

So, share away, my friend, what seems to be the problem? Be specific. 

You mention "43.7 Hp at 72 volts at 453 amps what does that sound like to you? Sounds like Humbug to me..". Well, which motor are you referring to? What would be your expected value ranges for Hp vs volts vs amps? Again, be specific.

I am sure that this sharing community can answer most any of your questions if you pose them accurately. 

Please give it another shot, I want to know what is wrong.

Eric




Georgia Tech said:


> Tesseract,
> 
> For startes 43.7 Hp at 72 volts at 453 amps what does that sound like to you? Sounds like Humbug to me..and for you to Hurl insults at me is unexcusable!! What Netgain giving you a commision or something? DAMN! tone yo Jets fool!
> 
> ...


----------



## Georgia Tech (Dec 5, 2008)

esoneson said:


> Georgia, slow down........take a deep breath. Obviously something has you very upset to trigger such a response. I, for one, will look past the tone of your posting and re-direct your attention to my post above (that, so far you have ignored).
> 
> "What bogus data? Please be specific. Curious minds want to know what you are talking about. What, exactly is incorrect, misrepresented or mis-stated? Again, please be specific."
> 
> ...


OK deep breath here...Yes the first thing that jumps out is the statemnet I pointed out in an earlier post I just pointed out...43.7 HP at those voltges and currents is wrong. Thats saying the motor is 100% effecient. Thats just old fasion lieing...yeah Yeah i know your going to say "thats just Marketing fluff", I just call it lieing...Then it seems to me that the curves them sefls seem really, Hmmm How do I say it..unrealistic?? or should I say not pratical or unusefull is a better word for it. I mean who would buy a 3000 dollar motor and then run it at 72 volts? The performance curves are at 72 volts? why? These kinds of Curves are what I would expect from GE trying to sell Motors to Hyster or something....what's the Max Current and for how long?? We have 2000 amp controllers.. What about giving REAL test data at 156 volts? How about real torque curves beyond 1000 amps? I mean we pay ALOT for these motor wheather some want to admit it or not! To say they have offered alot to the Ev community is giving them too much credit!! They are running a business, they are trying to do us any special favors...Now Paul Holms with his Open source controller (Revolt)??? THATS SPECIAL!!! THATS dedication and sacrifice!! He is an EV HERO all the way in may book...Warp's motors are NOT open source they are in it to make money Netgain PERIOD!

Maybe saying "Bogus data" was a bit too strong and over reacting, but when I read in another thread I started that someone else is sort of seeing the same thing I did. I Lunged at the situation but maybe too strongly..


----------



## xrotaryguy (Jul 26, 2007)

All right, let's cool things down a bit. If this continues, the thread will be deleted.


----------



## esoneson (Sep 1, 2008)

OK, now we are getting somewhere. True, Netgain is out to make money, capitalism is a good thing. True, the diagrams and curves available from Netgain are old and most likely outdated. There needs to be an update of the REAL numbers. 

Up until recently, there were very few components available that could stress these motors to their fullest capabilities. First you need a powerful controller to drive the motor. And one that gathers data and can report that data. Next you need a good dyno to apply the force necessary to stress the motor. Then you need an intelligent, caring individual to spend the time running tests and distributing the information to the community.

Until recently Zilla was the only monster of a controller available to get the task done. Now we have Soliton, thanks to the hard work of Tesseract and Qer. This is a powerful controller that has the ability to drive these motors beyond their limits. And thanks the the forward thinking of it's developers, this controller can record and make available, large volumes of real time data for analysis of those motors over a wide range of rpms/volts/amps etc.

Seems to me that the best way to 'correct' any 'misleading' data is to provide accurate testing with tests results being made public. I know that Tesseract has volunteered his time, knowledge and effort (all of which in this economy equates to money) to accumulate this data for the community. I salute him in his efforts. 

With competition comes better products at better prices. Kostov, Netgain and others will be tested and the differences in their products will be forthcoming to show what those differences really are.

Tesseract (and Qer) is/are a friend(s) to this effort. Support them and you will get your answers. 

And yes, we all are very proud of the efforts made by Paul Holmes and the contributors to the OpenRevolt controller which is aiding the DIYer to no small extent.

For now, I will wait for some accountable results provided by those that are willing to spend the time and effort to test the permutations and combinations of the components. I know it will be a huge effort.

Eric




Georgia Tech said:


> OK deep breath here...Yes the first thing that jumps out is the statemnet I pointed out in an earlier post I just pointed out...43.7 HP at those voltges and currents is wrong. Thats saying the motor is 100% effecient. Thats just old fasion lieing...yeah Yeah i know your going to say "thats just Marketing fluff", I just call it lieing...Then it seems to me that the curves them sefls seem really, Hmmm How do I say it..unrealistic?? or should I say not pratical or unusefull is a better word for it. I mean who would buy a 3000 dollar motor and then run it at 72 volts? The performance curves are at 72 volts? why? These kinds of Curves are what I would expect from GE trying to sell Motors to Hyster or something....what's the Max Current and for how long?? We have 2000 amp controllers.. What about giving REAL test data at 156 volts? How about real torque curves beyond 1000 amps? I mean we pay ALOT for these motor wheather some want to admit it or not! To say they have offered alot to the Ev community is giving them too much credit!! They are running a business, they are trying to do us any special favors...Now Paul Holms with his Open source controller (Revolt)??? THATS SPECIAL!!! THATS dedication and sacrifice!! He is an EV HERO all the way in may book...Warp's motors are NOT open source they are in it to make money Netgain PERIOD!
> 
> Maybe saying "Bogus data" was a bit too strong and over reacting, but when I read in another thread I started that someone else is sort of seeing the same thing I did. I Lunged at the situation but maybe too strongly..


----------



## Bowser330 (Jun 15, 2008)

Georgia Tech said:


> OK deep breath here...Yes the first thing that jumps out is the statemnet I pointed out in an earlier post I just pointed out...43.7 HP at those voltges and currents is wrong. Thats saying the motor is 100% effecient. Thats just old fasion lieing...yeah Yeah i know your going to say "thats just Marketing fluff", I just call it lieing...Then it seems to me that the curves them sefls seem really, Hmmm How do I say it..unrealistic?? or should I say not pratical or unusefull is a better word for it. I mean who would buy a 3000 dollar motor and then run it at 72 volts? The performance curves are at 72 volts? why? These kinds of Curves are what I would expect from GE trying to sell Motors to Hyster or something....what's the Max Current and for how long?? We have 2000 amp controllers.. What about giving REAL test data at 156 volts? How about real torque curves beyond 1000 amps? I mean we pay ALOT for these motor wheather some want to admit it or not! To say they have offered alot to the Ev community is giving them too much credit!! They are running a business, they are trying to do us any special favors...Now Paul Holms with his Open source controller (Revolt)??? THATS SPECIAL!!! THATS dedication and sacrifice!! He is an EV HERO all the way in may book...Warp's motors are NOT open source they are in it to make money Netgain PERIOD!
> 
> Maybe saying "Bogus data" was a bit too strong and over reacting, but when I read in another thread I started that someone else is sort of seeing the same thing I did. I Lunged at the situation but maybe too strongly..


Georgia i am with you bro...Its pretty funny trying to sell me a freaking drag racing Warp13 motor for 5 Grand and giving me data at a measily 72V...haha...

I just think we have to have patience with the data like others have said, additionally as you have said, this is a new community that is growing larger by the day...eventually the data we want will be available...the market just has to get there...

To your point about the cost of the motors it is sort of like what you were mentioning with the crate motors...its sort of like comparing getting your LS1 from ebay or getting an LSX crate motor from GM....you will pay a lot more for than confidence in your crate motor....but again to the previous point, at least they back up the cost with usable power data...

I will definitely be needing your help sourcing a GE (interpoled) 13"...hey if I can get that for 500$ or so...i highly doubt a performance rebuild will cost me 4,500$....what do you think?

If you are looking for higher voltage data curves you can check out the kostov motors...which are actually probably closer in relation to the GE motors as they are also interpoled.. http://kostov-motors.com then navigate to DC Series Traction Motors...prices are also cheaper than Warps...


----------



## Georgia Tech (Dec 5, 2008)

Bowser330 said:


> Georgia i am with you bro...Its pretty funny trying to sell me a freaking drag racing Warp13 motor for 5 Grand and giving me data at a measily 72V...haha...
> 
> I just think we have to have patience with the data like others have said, additionally as you have said, this is a new community that is growing larger by the day...eventually the data we want will be available...the market just has to get there...
> 
> ...


13 inch interpoled motor..ooooh man, that is is a tough one dude. I have not seen one yet not saying they are not out there. The 13 inchers I have seen the commutator bar count was in question, in both sepex verios and series. You would have more success with the series version. Now surprisingly I have seen the AC version of the 13 inch motor for what its worth. But my knowldge is limmited on AC motors. It might be that one would not need such a physically large machine to go AC. Major and Plamenator can check me on this. Now there was one fellow on here that DOES have a 13 inch motor that sounded like it had a fair number of bars, he was using it for a tractor, but it did not have interpoles. Now I am NOT saying that we could not take the exsiting 13 inch 29 bar motor and advance it and see if it will run on 144 volts and 2000 amps! I would LOVE do see this. Maybe we could see if a Big Guru Motor head like Jim Hufsted could take this 13 inch motor and maybe retro fit intpoles in it..It looks like it has the space. 
Have a look at this http://www.poormansev.com/id22.html He uses a large 13inch motor for his drag race, now I know he only goes 72 volts, but take a look at his commutator settup, it looks like he has well over 29 com bars which is encouraging! Now the key is to find a motor like this. Boy this talk is getting me excited again...
Oh by the way there is another guy who uses a 13 inch motor for is chevy S-10 he calls it Smoke screen. check out his youtube: http://www.youtube.com/watch?v=rya6QaQOYfg
He ACTUALLY has this motor for sale. It was a modified Forklift motor as well He runs it direct drive no tranny. That motor is one Bad dude man.
http://evdl.org/archive/#nabble-td461123%7Ca461123


----------



## Plamenator (Mar 6, 2009)

I am certain that a non-interpoled 29 bar motor will not run at 144V - I think it will even not run at 60-72V assuming rpm are above 3000.
Sure, it will spin, but collector will overheat in 20-25min from arcing.
Our motors use 65 bars. Without interpoles the limit is around 75-80V.
Interpoles bring it up to around 250V.

AC motors in principle have less power per kg assuming same voltage.
Hence a non-water-cooled 13" AC motor at around 250-288V can be compared to an 11" DC in terms of power. Torque curve of the AC is also weaker on the peak side.
But you do get regen, water cooling, no collector to worry for and full enclosure from water/dust/mud. Still I think that at NEDRA, DC will always win as far as voltage stays below 300V.

Just an opinion of course....


----------



## Plamenator (Mar 6, 2009)

And we also tested the effect of advancing brushes on non interpoled motors - gives 10-15C change in collector temp after a 60min run.
Note that limit for a collector temp is 140C.


----------



## Georgia Tech (Dec 5, 2008)

Plamenator said:


> I am certain that a non-interpoled 29 bar motor will not run at 144V - I think it will even not run at 60-72V assuming rpm are above 3000.
> Sure, it will spin, but collector will overheat in 20-25min from arcing.
> Our motors use 65 bars. Without interpoles the limit is around 75-80V.
> Interpoles bring it up to around 250V.
> ...


Thankyou SOO much for this response...Well I will have to change my planes then..  thanks for your response on the other thread as well..


----------



## Plamenator (Mar 6, 2009)

What about the 10" 72V sepex interpoled? Should be a good motor albeit the low voltage . You can probably run it higher depending on rpm - too high rpm will pose a mechanical danger for the collector.
It is very difficult to judge a motor just by the number of comm bars.
If you use 100A you can probably get away with 80V. If rpm are 1000-2000 you may also get away.
But for 4000+ rpm and 200-250A, I would say not more than 60-72V.
Of course this is for running it all the time at 60-72V. 
For 5-10-15min it will probably be OK even with 100V. 

Note that this opinion is subjective and relies heavilly on extrapolation.
What exactly are you building?


----------



## jackbauer (Jan 12, 2008)

Dunno if this is any help but here are a few pics of a 13" forklift motor i got for free! Has lots of com bars. Manufactured by a company called pyroban and is rated at 10kw 80v one hour.


----------



## Bowser330 (Jun 15, 2008)

I don't know what others think, but I feel DC motor rpm is VERY important.

Torque @ rpm/constant = power 

Example, if lets say 1000A is 300ftlbs of torque in an 11" motor...and with my high voltage interpoled DC motor I am able to pull 1000A @ a max rpm of 4000rpm....

Then 300 * 4000/5252 = power, 228hp!

So if interpoles can help and advancing the motor can also help then I am all for it...throw me in some kevlar banding too!

This is why the Warp11HV is so potent...its suppose to be able to run up to 9000rpm!!...I really hope soon we can see a power curve for this motor running at 336V (interpoles+advanced) and 1000+Amps...If its able to pull 300ftlbs up to 5252rpm then thats 300hp...


----------



## Georgia Tech (Dec 5, 2008)

Plamenator said:


> What about the 10" 72V sepex interpoled? Should be a good motor albeit the low voltage . You can probably run it higher depending on rpm - too high rpm will pose a mechanical danger for the collector.
> It is very difficult to judge a motor just by the number of comm bars.
> If you use 100A you can probably get away with 80V. If rpm are 1000-2000 you may also get away.
> But for 4000+ rpm and 200-250A, I would say not more than 60-72V.
> ...


Well I did not want to bother you with too many questions but i recently purchased this motor wich is still in the mail and has not arrived yet:
http://www.flickr.com/photos/[email protected]/
Which THIS IS a Sep-Ex motor with interpoles i also have a GE 11 that is a series that DOES not have Interpoles...I bought this motor because I was reading on this forum how Interpoles have such a profound impact on motor asspects on how it, not to mention regen braking. So I wanted to run this Sep-x at around 144 volts from around 800 to 3200 rpm Max. Is this possible? and get about 200Kwatts for short periods of time. Like I said I have a GE 11 with 49 collector Bars as well..I could use it as well...


----------



## Plamenator (Mar 6, 2009)

Bowser, the interpoles create a neutral zone in the brush area.
Advancing the brushes will then move the brushes outside this neutral zone and will make commutation worse.
So simply do not do it on an interpoled motor - it will not improve it!


----------



## Georgia Tech (Dec 5, 2008)

Man I tell you one of the roughest discusion on this thread turned out to be one of the better discsusions I have had!!  Like they always say you can't have rain bow without the rain...can't have growth with out the pain... Boy did this thread start of Painfull


----------



## Plamenator (Mar 6, 2009)

Georgia Tech said:


> Well I did not want to bother you with too many questions but i recently purchased this motor wich is still in the mail and has not arrived yet:
> http://www.flickr.com/photos/[email protected]/
> Which THIS IS a Sep-Ex motor with interpoles i also have a GE 11 that is a series that DOES not have Interpoles...I bought this motor because I was reading on this forum how Interpoles have such a profound impact on motor asspects on how it, not to mention regen braking. So I wanted to run this Sep-x at around 144 volts from around 800 to 3200 rpm Max. Is this possible? and get about 200Kwatts for short periods of time. Like I said I have a GE 11 with 49 collector Bars as well..I could use it as well...


The label says it is S3-28% motor which means a pump motor???!
The motor can work 2.8min out of every 10min and is not an EV motor.
Excitation also is probably not sepex but compound which is typical of pump motors. 
Can anyone else also check it?


----------



## Georgia Tech (Dec 5, 2008)

Plamenator said:


> The label says it is S3-28% motor which means a pump motor???!
> The motor can work 2.8min out of every 10min and is not an EV motor.
> Excitation also is probably not sepex but compound which is typical of pump motors.
> Can anyone else also check it?


Uhh Ohh!! It looks like I struck out twice!! LOL  Oh well I guess I will see if I can get the interpoles out or something.. lol


----------



## major (Apr 4, 2008)

Plamenator said:


> Excitation also is probably not sepex but compound which is typical of pump motors.
> Can anyone else also check it?


This was confirmed in post #12 of this thread http://www.diyelectriccar.com/forums/showthread.php?t=32534 Looks like the same motor to me.

major


----------



## Georgia Tech (Dec 5, 2008)

major said:


> This was confirmed in post #12 of this thread http://www.diyelectriccar.com/forums/showthread.php?t=32534 Looks like the same motor to me.
> 
> major


 
Your right Major...it is... and thanks for the response

...boy I really feel like a fool for buying it now...250.00 for shipping and 250.00 for the motor....oh well ....guess thats what I get for not buying $3500.00 warp I guess..


----------



## alexcrouse (Mar 16, 2009)

Georgia:
43.7 Hp at 72 volts at 453 amps
72*453=32616watts
32616/746=43.721179 Hp
Whats the problem? There is no claim this is a dyno number. multiply that by the advertised efficiency, and can it. 

37hp at 85% still isnt bad, the torque is what matters.



Georgia Tech said:


> Tesseract,
> 
> For startes 43.7 Hp at 72 volts at 453 amps what does that sound like to you? Sounds like Humbug to me..and for you to Hurl insults at me is unexcusable!! What Netgain giving you a commision or something? DAMN! tone yo Jets fool!
> 
> ...


----------



## Georgia Tech (Dec 5, 2008)

alexcrouse said:


> Georgia:
> 43.7 Hp at 72 volts at 453 amps
> 72*453=32616watts
> 32616/746=43.721179 Hp
> ...


There is no such thing as a motor with no losses.


----------



## Tesseract (Sep 27, 2008)

Georgia Tech said:


> There is no such thing as a motor with no losses.


Alexcrouse's post got me to thinking as to what got you all riled up in the first place, so I went over to NetGain's site and looked at each motor's performance chart until I found the exact numbers you've quoted here. For those of you interested, they come from the WarP 11 and the performance chart is at the following link:

http://www.go-ev.com/images/003_20_WarP_11_SpreadSheet.jpg

Notice how there are two columns labeled H.P. - one is H.P.e and the other is H.P.m? "E" stands for "electrical" and "m" stands for "motor". So the _INPUT_ (electrical) power is 43.7hp while the _OUTPUT_ (motor) power is 37.1hp. Hell, there is even a column labeled efficiency...


----------



## Georgia Tech (Dec 5, 2008)

Tesseract said:


> Alexcrouse's post got me to thinking as to what got you all riled up in the first place, so I went over to NetGain's site and looked at each motor's performance chart until I found the exact numbers you've quoted here. For those of you interested, they come from the WarP 11 and the performance chart is at the following link:
> 
> http://www.go-ev.com/images/003_20_WarP_11_SpreadSheet.jpg
> 
> Notice how there are two columns labeled H.P. - one is H.P.e and the other is H.P.m? "E" stands for "electrical" and "m" stands for "motor". So the _INPUT_ (electrical) power is 43.7hp while the _OUTPUT_ (motor) power is 37.1hp. Hell, there is even a column labeled efficiency...


 Tesseract,
If you want to be the winner of this fight you can be...so be it your the winner...It is what it is...I have seen PLENTY of sights that said eactly what I just said 100% effecint with out specifing eHP and mHP to me its lieing...Also go through and read a few Plamenator's comments you will find them intresting and I think he has very good qualifications to back him.


----------



## Georgia Tech (Dec 5, 2008)

By the way Tesseract, when you made this comment a while back what did you actually mean by this? I often wondred that. 



Tesseract said:


> So, uh... what are you planning on doing with these modules, GT? Gonna make yerself a big, bad 2000A motor controller with 'em?


----------



## alexcrouse (Mar 16, 2009)

I am an electric engineer, and never claim a loss-less motor. I chose 85% efficiency because thats one of the numbers on their chart, NOT EVEN their peak performance.


----------



## Georgia Tech (Dec 5, 2008)

alexcrouse said:


> I am an electric engineer, and never claim a loss-less motor. I chose 85% efficiency because thats one of the numbers on their chart, NOT EVEN their peak performance.


I agree with you, I always use 85% as well, thats way they should have said 37 HP in their advertisement not 43.7 HP


----------



## Bowser330 (Jun 15, 2008)

Plamenator said:


> Bowser, the interpoles create a neutral zone in the brush area.
> Advancing the brushes will then move the brushes outside this neutral zone and will make commutation worse.
> So simply do not do it on an interpoled motor - it will not improve it!


really?

so then why does netgain rate their warp11 Hv as 288V neutral and 336V advanced?

http://www.evcomponents.com/ProductDetails.asp?ProductCode=WARP+11+HV&Show=TechSpecs

I am confused


----------



## Plamenator (Mar 6, 2009)

Bowser330 said:


> really?
> 
> so then why does netgain rate their warp11 Hv as 288V neutral and 336V advanced?
> 
> ...


You should really ask Netgain that question. I am confused too.
I will try to provide below a more detailed explanation so you can decide for yourself (I am sure Major will catch me if I make an error; he is a merciless man ).

Now, the interaction between rotor and stator fields in theory creates a neutral zone just above the poles. Therefore we put the brushes there.
In reality, a process called armature reaction (http://books.google.bg/books?id=vmg...vanced brushes commutation interpoles&f=false), causes this neutral zone to shift in the direction of rotation (by 2-20mm?). Therefore the brushes are not any longer in their optimal position and people advance the brushes to minimise arcing (note that over-advancing actually makes arcing heavier).
In contrast to brush advancing, interpoles create a counter field that cancels armature reaction and returns the neutral zone just above the poles - and this is regardless of rpm or amps (brush advancing is optimal only for given rpm+amps).
Imagine that you now advance the brushes of an interpoled motor - in effect you will move them outside the already centered neutral zone and arcing will increase. Hence the conclusion that advancing will make matters worse.

When comparing Kostov to our competition, you will notice that we have 65 collector bars vs 59 for our competition (has to be confirmed). Our tests with 65 bars show that commutation is acceptable to about 240-260V. How one can manage to get to 288-336V with less comm bars is a mystery to me especially given rpm in the 8000-9000 region (assuming centrifugal force is not a problem purely mechanically). If we are to follow common rating practices, we should call this a 350V motor relying on the fact that it will spend most of it time at 150-200V and never reach 350V for more than 2-3min. We cannot accept that - when we rate a motor at 250V, it means it can operate for 60min at the voltage and we have actually tested it. I assure you that tests at 72 and 192V for example will give you very different results even for the same motor at the same amps.

Further, if one provides tests only at 72V, how does one know that the interpole windings are optimal at 288V??!? At 72V interpoles are not that important and such tests are not a good proxy for commutation at 288-336V. You could say there probably is a formula for calculating the proper number of loops. This formula has to take in account brush material, collector material, rpm, brush friction, diameter of rotor+collector, number of main coils loops, number of collector bars, length of rotor package...pretty much everything. This formula is not usefull in practice and therefore we use real voltage tests despite the costs.

Of course, read the above from a critical perspective as I can be biased.


----------



## Tesseract (Sep 27, 2008)

@Bowser330: Plamen from Kostov is correct - and I am sure major would agree - in that you can _either_ use interpoles or advanced timing to improve commutation at higher voltages _BUT NOT BOTH_. 

[deleted by request]


----------



## Plamenator (Mar 6, 2009)

Georgia Tech said:


> I agree with you, I always use 85% as well, thats way they should have said 37 HP in their advertisement not 43.7 HP


The problem from my point of view is not efficiency, but the fact that both 37/43.7HP are overload points (where motor can last 5-10-15min) as nominal (60min) amps are in the 250A area.


----------



## major (Apr 4, 2008)

Plamenator said:


> Now, the interaction between rotor and stator fields in theory creates a neutral zone just above the poles. Therefore we put the brushes there.


Hi Plamen,

Nice explanation and it tells part of the story. There is actually more to it, but I'm not about to attempt to write a book on the subject. 

But to stay in character (merciless), this neutral zone you speak about is inbetween the main field poles, not "above" the poles. The brushes are positioned in line with the center of the poles, but the armature coils connected to the commutator segments touching the brush are offset 45 degrees (for 4 pole machines). So the armature coils being commutated are inbetween the main poles, not above them.

If you have a north pole generating a positive voltage on an armature conductor, then when that conductor rotates around under the adjacent south pole, it will have a negative voltage. Obviously at some point, that generated voltage crosses zero. This occurs midway between the north and south poles when there is zero armature current. And "neutral zone" is somewhat misleading because it is really a zero crossing. But by proper design there can exist a "zone" of low voltage either side of this zero.

Commutation is a complex process to analyze. It is the forced reversal of current, not switching off and on. So besides having to deal with the influence of external fields, the designer must also account for the self induced voltage in the coils.

Regards,

major


----------



## Georgia Tech (Dec 5, 2008)

Plamenator said:


> The problem from my point of view is not efficiency, but the fact that both 37/43.7HP are overload points (where motor can last 5-10-15min) as nominal (60min) amps are in the 250A area.


Well you just might be correct by saying they are overload points but I hope not.. haha... LOL!! Thats for Netgains sake. 

Let me ask you RPM plays a BIG role in all this discusion of interpoles. Lets say we over volt a motor by double to 144 volts it rated at 72 volts. But, we keep the RPM at about 3200 RPM does arching become an issue then? Is the advacneing and Commutation issue due to the RPM along with the voltage? Or is it JUST voltage? I want to run my forklift motor at 144 volts but I want to keep the RPM at or under 3200 RPM. Would it need to be advanced?


----------



## major (Apr 4, 2008)

Tesseract said:


> @Bowser330: Plamen from Kostov is correct - and I am sure major would agree - in that you can _either_ use interpoles or advanced timing to improve commutation at higher voltages _BUT NOT BOTH_.


I don't agree 100%. I have seen examples where brush shift was used on interpole machines. It is uncommon. And I suspect that it was a misprint by Netgain.


----------



## Georgia Tech (Dec 5, 2008)

Tesseract said:


> On a completely separate note... there has been a rash of extreme rudeness on this forum lately. My rule for dealing with others on the internet is very simple: pretend the other person is in the same room, and if that doesn't sufficiently restrain me, pretend the other person is also 6'5", 300# and has a black belt in Kung Fu. If the other person is behaving like a spoiled brat that just had his toys taken away, then I simply ignore that person.
> 
> This is all I have to say on the matter. I don't mind a good challenge, argument or debate, but if you have to resort to personally attacking me to make your point I'll basically conclude it's because you either have no control over your emotions or because your point has no merit.


You have not dropped this yet? Evne after the moderator has said stop this and you still keep it going!! DROP IT WOULD YOU!!!! before you get us both killed!!! Dang, remembr your trying to sale your high dollar fancey new controller, your not being a good representative for evnetics...


----------



## major (Apr 4, 2008)

Georgia Tech said:


> Lets say we over volt a motor by double to 144 volts it rated at 72 volts. But, we keep the RPM at about 3200 RPM.....


Hey GT,

How do you double the motor voltage and keep the RPM the same?

major


----------



## Georgia Tech (Dec 5, 2008)

major said:


> And I suspect that it was a misprint by Netgain.


Really ???? Nahh....lol...can't be..


----------



## Tesseract (Sep 27, 2008)

[deleted by request]


----------



## Georgia Tech (Dec 5, 2008)

major said:


> Hey GT,
> 
> How do you double the motor voltage and keep the RPM the same?
> 
> major


 LOL Kinda silly how I did not explain...Well for the case of my GE 11 series motor, I was wanting to have a RPM sensor to go back to the controller. That the controller would limmit the RPM...Sort of like how current limmit would work. Being that the voltage is high I now have More usebale Torque accross a wider RPM rang. If that mad sense what I said. 

I was also thinking about this Schawbmualar Compound motor that I just bought and just found out it is useless. I figured If I double the field from 72 to 144 votls and double the Arm volts then the RPM should be the same as it was at 72 volts(2600 RPM). Thats IF the Feild is not driven into saturation...BIG IF!! But I have to do something Hey it has interpole so what the heck huh....

Would this work you think? Am I off basis here or what?


----------



## Plamenator (Mar 6, 2009)

major said:


> I don't agree 100%. I have seen examples where brush shift was used on interpole machines. It is uncommon. And I suspect that it was a misprint by Netgain.


What is the point in this brush advance on interpoled motors?
Would you not agree that advancing the brushes of an interpoled motor actually worsens commutation as it moves them away from the zero crossing/"neutral zone"?


----------



## major (Apr 4, 2008)

Plamenator said:


> What is the point in this brush advance on interpoled motors?
> Would you not agree that advancing the brushes of an interpoled motor actually worsens commutation as it moves them away from the zero crossing/"neutral zone"?


Well, yes, if you assume your interpoles are working perfectly at your particular load conditions. However if this is not the case, then shifting the brushes one way or the other can if fact present an opposing voltage on the commutated coils which can reduce arcing. I've heard of old submarine motors which had adjustments made by the sailor while under load to optimize commutation. It's not unheard of, but uncommon. And I don't think that a fixed advance on an interpole motor would make sense for an EV. 

Regards,

major


----------



## Georgia Tech (Dec 5, 2008)

Major or Plamenator,

If I were to Limmit the RPM while running Higher voltage would this Help in Bad commutation? Is this Bad Commutation due to just High voltage? Or does High RPM along with High Voltage pose a problem with arching and bad commutation?


----------



## Plamenator (Mar 6, 2009)

I think that rpm are a secondary determinant of commutation.
If you already have bad commutation, high rpm will make it even worse as far as the collector is concerned (more sparkling and more friction).
There are low rpm (1000-2000) forklift motors at 80V that can get by without interpoles but we cannot make an EV motor (4000-6000rpm) without interpoles at 80V...
At the same time high rpm mean better ventilation so your stator/rotor windings will be cooler but this is not of big use if your collector is overheated, is it?!
My understanding is that the primary determinant of commutation (assuming correct brush material and size) is voltage or to be more precise the voltage in between two adjacent collector bars. This inter-bar voltage should be the nominal voltage divided by the number of comm bars (Major?). Hence the more bars you have, the better but at the the same time more bars mean smaller conductors which limits the current. Therefore you have to find some balance.

Regarding your compound motor, you know it has 2 series coils + 2 shunt coils? Maybe you can find someone to replace your 2 shunt ones with 2 series coils (same as the existing) and you will get a decent series motor out of it  assuming you decrease nominal amps by about 25%. Just an idea, not sure if it will work.
Also, I think there is a UK company, whose name is escaping me, which makes compound motor controllers.


----------



## major (Apr 4, 2008)

Georgia Tech said:


> =Is this Bad Commutation due to just High voltage?


The limit for acceptable commutation for a particular motor design is a function of current, voltage and RPM. Notice the commutation limit lines on this curve which Dennis posted in another thread. They are in the upper right. http://www.getransportation.com/na/en/docs/1136706_1243949620_series wound.pdf Those limit lines appear to be a similar shape as the power curves. This is because that for a particular motor design, the current, voltage and RPM are all related as is the power. 



Plamenator said:


> This inter-bar voltage should be the nominal voltage divided by the number of comm bars (Major?).


I think this bar-to-bar voltage number is a rule of thumb. So it depends on whose thumb. If I were talking about it, I would use the number of bars between positive and negative brushes. So a 65 bar commutator would have 16 bars between + & -. Bar-to-bar voltage would be applied voltage divided by 16.

Regards,

major


----------



## Georgia Tech (Dec 5, 2008)

Many thanks to the both of you...Plamenator, are you saying that I have 2 poles wound as series and two as shunt?? Boy I hope not . I really WILL have a mess on my hands then! What about just makeing it an entirely sepex motor? Is a Straight series that much better? I guess it would be a series with Interpoles...Man I goofed big time 500 bucks down the tubes.......Oh well..
I have an 11 inch GE that could use the interpoles...I wonder if they would fit?

Major I took that big 13 inch monster motor and ran it on 24 volts for about 15 minutes last night at 2400 RPM...It held up decent...Wondering If I should try 36 volts to see if it will hold at 3600 RPM...this is the MAX RPM that I need it to run at...But like I said only 29 Com bars..


----------



## major (Apr 4, 2008)

Georgia Tech said:


> are you saying that I have 2 poles wound as series and two as shunt??


GT,

Look back at the drawing. It shows 4 series coils and 4 shunt coils. So each of the 4 poles has series turns and shunt turns in its respective coil. I will guess effectively very few series turns by the appearance of the speed/torque curve. More like a compensated shunt motor.



Georgia Tech said:


> Major I took that big 13 inch monster motor and ran it on 24 volts for about 15 minutes last night at 2400 RPM...It held up decent...Wondering If I should try 36 volts to see if it will hold at 3600 RPM


I have to stick to my standard advice. When testing these motors at no-load, stick to 12 volts, max. I suspect that such a motor would be good for 4000 RPM, but treat that as a guess.

major


----------



## Plamenator (Mar 6, 2009)

I always thought that series motors have 4 series coils, compound have 2 series+2 shunt coils and sepex have 4 shunt coils but this motor indeed has 8 coils. I suppose the series coils facilitate the starting of the motor?
In fact, doesn't this make the motor with shunt excitation rather than compound?
Given that it has 4 shunt coils, which according to you are dominant, do you think Georgia can use a Sepex controller to drive it? Will the series coils be of benefit in such a case?


----------



## Georgia Tech (Dec 5, 2008)

major said:


> GT,
> 
> Look back at the drawing. It shows 4 series coils and 4 shunt coils. So each of the 4 poles has series turns and shunt turns in its respective coil. I will guess effectively very few series turns by the appearance of the speed/torque curve. More like a compensated shunt motor.
> 
> ...


Major you are a good man!! thanks for taking your time to help meonce again.....Maybe I'll do a Youtube of this beast running...


----------



## Georgia Tech (Dec 5, 2008)

Plamenator said:


> I always thought that series motors have 4 series coils, compound have 2 series+2 shunt coils and sepex have 4 shunt coils but this motor indeed has 8 coils. I suppose the series coils facilitate the starting of the motor?
> In fact, doesn't this make the motor with shunt excitation rather than compound?
> Given that it has 4 shunt coils, which according to you are dominant, do you think Georgia can use a Sepex controller to drive it? Will the series coils be of benefit in such a case?


Man you have been a big HELP to us here at this forum thanks so much for your input....I hope Kostov sell milions of motors...Means that EV are taking off!!


----------



## Georgia Tech (Dec 5, 2008)

OK so when I get this motor in the mail and take it to a shop which would be better?
To make it an all series motor or a Sep-ex motor. Keeping in mind this DOES have interpoles..


----------



## major (Apr 4, 2008)

Plamenator said:


> I always thought that series motors have 4 series coils, compound have 2 series+2 shunt coils and sepex have 4 shunt coils but this motor indeed has 8 coils. I suppose the series coils facilitate the starting of the motor?
> In fact, doesn't this make the motor with shunt excitation rather than compound?


Yes. That is basically the compensated shunt motor. The 2-series, 2-shunt coil design works well for compound motors which are 50/50 series/shunt. It is less expensive to manufacture that way and makes little difference magnetically. But the compensated shunt motor has just a few series turns, so might be like 80% shunt/20%series. So both series and shunt turns are wound on each pole.




Plamenator said:


> Given that it has 4 shunt coils, which according to you are dominant, do you think Georgia can use a Sepex controller to drive it? Will the series coils be of benefit in such a case?


Yes, the series turns will assist in motoring if the motor is used as a SepEx. But the series turns would be differential compounding when in the regeneration mode. This could be overcome with the control of the field. It really depends if he can figure out how to control the motor, which is a very good machine from what I see. Germans can do a good job with machines 

Regards,

major


----------



## Plamenator (Mar 6, 2009)

Georgia Tech said:


> OK so when I get this motor in the mail and take it to a shop which would be better?
> To make it an all series motor or a Sep-ex motor. Keeping in mind this DOES have interpoles..


I think making 4 entirely new sepex coils is better because:
1) The existing main windings have their separate bolt connections already (E1&E2) and you will not have to think on how to weld the new sepex coils in series with the rotor and the interpoles. Making it sepex will also allow you electrical reversing and regen.
2) Round wire is much easier to work with and you will not have problems in shaping the coil around the existing main poles. You just need to find a motor repair shop that is willing to do it for you; you can use wooden model to wind the coil around it (winding by hand is not a good idea).
3) you can employ mechanical (rather than welding) joining methods to link the 4 new sepex coils together; note that sepex current is usually 2-50A with 10-15A as nominal.
4) Do not forget to add a thermal cut-off in the new sepex coils with a 180C threshold (definitely use class H insulation wire and materials).
5) If you are lucky you will manage to get sepex coils that allow you to go to 120V while keeping reasonable rpm.
6) As a very rough indication use 1.5-1.8mm round wire with as many loops as you can fit (100-200?) leaving about 5-10mm of free space on the sides of the coil for ventilation.
7) Once you determine voltage go either for Curtis sepex controller at 96V or Kelly sepex at 120V both with regen  - and the new coils should not be more than 100-150$....maybe...
7) Wait for Major's opinion before proceeding further


----------



## Georgia Tech (Dec 5, 2008)

Plamenator said:


> I think making 4 entirely new sepex coils is better because:
> 1) The existing main windings have their separate bolt connections already (E1&E2) and you will not have to think on how to weld the new sepex coils in series with the rotor and the interpoles. Making it sepex will also allow you electrical reversing and regen.
> 2) Round wire is much easier to work with and you will not have problems in shaping the coil around the existing main poles. You just need to find a motor repair shop that is willing to do it for you; you can use wooden model to wind the coil around it (winding by hand is not a good idea).
> 3) you can employ mechanical (rather than welding) joining methods to link the 4 new sepex coils together; note that sepex current is usually 2-50A with 10-15A as nominal.
> ...


Thanks Man AWSOME response! Thanks for your help.  Yeah I would like to see what major says. I plan on taking it to Warfield of all places which is owns Netgain...LOL go figure... I have to see how much they will charge to do this. Hopefully it will come in the mail today..


----------



## Georgia Tech (Dec 5, 2008)

Well I just got off the Phone with Warfield and they can change that shaft out No problem. They also said they could rewind the fields as well. To be either Sepex or Series. I will drop it off and see what they say..


----------

