# What hp motor needed for direct drive?



## major (Apr 4, 2008)

wilkes5 said:


> looking to move a 3000+lbs car with direct drive. Is a 40 hp motor enough to it up to 60 mph? more specs are "12v or 24v field and 200 amps with 108 volts armature for full power" thanks


Hi wil,

This seems to be a bad question. How do you figure that voltage and current can produce 40 hp? And then, while it may be possible for 40 hp to propel a 3000 lb car at 60 mph in direct drive, you may get extremely bored waiting for it to happen. Also the 12 or 24V field is a clue this isn't going to work out well.

Regards,

major


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## wilkes5 (Jun 1, 2012)

roger dude

clue!? what motor specs would make the 3000lbs sporty ( guessing keep the transmission)?
maybe something industrial, mabye AC motors?


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## mizlplix (May 1, 2011)

Even with a transmission, An AC or DC motor will need more voltage and current to perform satisfactorily.

3,000#.....? A 9" DC motor and 850 Amp controller, plus batteries to feed it.(sporty)

Like.... a minimum of 96Volts-150 amps= to maintain 45 MPH on flat ground, and that will have a slow acceleration.

More like 120 volts and 300-400 amps with a transmission for a decent take off and keep up with traffic.

And 144 volts-800+ amps -transmission for sporty.

EXAMPLE: I am running a 2,000 Lb car- 125 volts-500+ amps and a transmission for sporty. (but not V8 corvette)

That weight is your real challenge as it harms your take off and mileage both.

My $.02,
Miz


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## wilkes5 (Jun 1, 2012)

mizlplix said:


> Even with a transmission, An AC or DC motor will need more voltage and current to perform satisfactorily.
> 
> 3,000#.....? A 9" DC motor and 850 Amp controller, plus batteries to feed it.(sporty)
> 
> ...


thanks for the info dude, talked to the guy and he mailed me back saying....

"If you ask question state plainly that you need a controller that would give 24 volts to the field and 108 volts to the field and can provide 300 amps continuous. If this does not clarify matters then just email me with more specific questions" 

in the email preceeding he said....

"For acceleration the armature will take more than 500 amps which is why it is intermittent duty at those amps"

the motor is older military, and considered by the guy ..

"You see in many if not most instances the shunt field is wired in parallel with the armature( that is why they are called shunt motors) and so both get the same voltage or the voltages are very close"

he also told me brake regen is easier on DC than AC, think he said the motor was capable, DO YOU agree? don't you need a special controller?

thanks


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## wilkes5 (Jun 1, 2012)

he's looking for a matching controller to get, do you guys have any ideas?

also, if the shunt motor goes into the camaro (3000lbs) with manual transmission, it won't be sporty? 

how many regular 12volt batteries are needed for a range of 50 miles with the....

1) shunt motor
2) warp 9
3) industrial DC/AC motor (can you tell me specs of industrial motors? and do all industrial motors need to be rewound?)


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## dougingraham (Jul 26, 2011)

wilkes5 said:


> how many regular 12volt batteries are needed for a range of 50 miles with the....


Too many!

The motor choice doesn't matter as soon as you indicate 12 volt batteries (assuming you mean lead acid). I am pretty sure if you try to use 12V lead acid batteries you won't be happy. They just weigh too much.

A 3000 lb car would typically take 300 wh/mile. So to go 50 miles you need about 15kwh of batteries. To make this work with Lithium is pretty easy because they don't weigh all that much. I would oversize the pack by at least 30% with lithium so you get long life with your 50 mile range. This means you want 21.4kwh of batteries. Typically with lithium and a desired range of 50 miles the car is going to end up weighing about the same as when it had the ICE in it. Certainly within a couple of hundred lbs more or less. The theory says you need 15kwh of batteries. With Lead Acid you could in theory do this with about 12 100AH lead acid batteries. This turns out to be not nearly enough for several reasons. Reason 1 is the batteries wont last long at all if you discharge them all the way every time. It is generally considered a good idea to use only the top 50% of the pack if you want it to last any length of time. So you now require 200AH of batteries. The second reason is the Peukert effect. A 100AH battery only puts out 100AH if discharged over a 20 hour time frame. We typically are discharging at a half hour rate on the average but with bursts much higher. You only get about 60% of the capacity when you discharge at this rate. So you basically need to double it again. What would have been about 330 lbs of lithium (15kwh or 470lbs for the 21.4kwh pack) has turned into 5640 lbs of lead acid batteries. Because the car now weighs about 8200 lbs you need to beef up the car to carry that extra weight and then because it is so much heavier you need even more batteries to make your 50 mile range (41kwh of batteries minimum). You have reached a point of diminishing returns where you simply cannot add enough batteries to overcome the additional weight of the additional batteries. And this doesn't even take into account that you have no place to put all those batteries. It looks to me like around 15 to 20 miles range is about the best you can do with Lead Acid. This is more like 80 to 100 miles with LiFePo4 prismatic cells. I am not saying you can't do better than this because it can be done. It requires a lot more attention to detail and you may not end up with a car you want.


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## major (Apr 4, 2008)

wilkes5 said:


> "If you ask question state plainly that you need a controller that would give 24 volts to the field and 108 volts to the field


24V to the field......108V to the field  Which is it?



wilkes5 said:


> If this does not clarify matters then just email me with more specific questions"


Not clear, but let's assume he means 24V to the field and 108V to the armature.



wilkes5 said:


> "You see in many if not most instances the shunt field is wired in parallel with the armature( that is why they are called shunt motors) and so both get the same voltage or the voltages are very close"


If you wire the 24V field in parallel with the armature which is at 108V, the field sees 108V and yes, it is then wired as a shunt motor but the field will burn up in short order because it has like 4 or 5 times too much current.



wilkes5 said:


> he also told me brake regen is easier on DC than AC, think he said the motor was capable, DO YOU agree?


With the proper controller and motor, regeneration is just as easy with AC or DC. The only real fit you have is with DC series motors because they make unstable generators. There is a narrow region where a PM or shunt or SepEx DC motors can regenerate without a controller but it is such a narrow band of speed and load it is irrelevant to the discussion.


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## wilkes5 (Jun 1, 2012)

dougingraham said:


> Too many!
> 
> The motor choice doesn't matter as soon as you indicate 12 volt batteries (assuming you mean lead acid). I am pretty sure if you try to use 12V lead acid batteries you won't be happy. They just weigh too much.


alright sorry, any cheaper altrenatives to lithium WHICH IS MADE IN USA (are lead acid the same as 12volts)?

might just stick with 10 mile range, would it be possible? you can short anwser, sorry for bad questions.


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## wilkes5 (Jun 1, 2012)

major said:


> 24V to the field......108V to the field  Which is it?


 
My question....

"when told the motor specs for the 40 hp "12v or 24v field and 200 amps with 108 volts armature for full power" some guys on the diyelectric forum did't think it would work"

His response...

"If you ask question state plainly that you need a controller that would give 24 volts to the field and 108 volts to the field and can provide 300 amps continuous. If this does not clarify matters then just email me with more specific questions"

, so, might have to ask him about it? 
pretty sure he ment 24v field /108 armature / 300 amps contiuous/ 500 amps intermittant (redline?)


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## wilkes5 (Jun 1, 2012)

"And 144 volts-800+ amps -transmission for sporty" can a industrial AC/DC motor have such specs? 

if so, price range (used, cheapest)

if so, how easy to get regen? is it all in the controller?


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## major (Apr 4, 2008)

wilkes5 said:


> My question....
> 
> "when told the motor specs for the 40 hp "12v or 24v field and 200 amps with 108 volts armature for full power" some guys on the diyelectric forum did't think it would work"
> 
> ...


So he changes his story and leaves you guessing? Have you bought his motor yet? It sounds like an old military or aircraft starter/generator. 

Now: 108V * 200A = 21.6kW. At ~75% efficiency would be 22hp.

108V * 300A = 32.4kW. Would give you 40hp if it was 92% efficient, which is a stretch.

These old starter/generators are solid machines. It could possibly work if you knew what you were doing and could build a proper controller for it. There is not a readymade off-the-shelf controller which will make this machine work well for you.


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## wilkes5 (Jun 1, 2012)

kind of need to know if a controller can be had which will allow regen?

how hard are controllers to make? do you need a custom PCB board, or can you just wire the parts together? thanks


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## wilkes5 (Jun 1, 2012)

even with everything up and running, it will have suggesh performace and not take hills well? top speed? accerelation?


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## onegreenev (May 18, 2012)

> These old starter/generators are solid machines. It could possibly work if you knew what you were doing and could build a proper controller for it. There is not a readymade off-the-shelf controller which will make this machine work well for you.


That is what we were trying to do with the Kelly Controllers. The last one tried just could not handle high amperage current back through for charging the batteries. These motors put out a lot of amperage in regen mode. With very little regen under load it did ok but no real feel of engine braking or any thing like that. I turned up the amps and blew the controller under regen. With no REGEN the controller worked great with these motors. It is a software upgrade but not ready for prime time and the project was scrapped. 

Contactors are the way to go if you use these motors if you want Regen. I do not have the proper setup for contactors to give you. I tried to find a source to build another contactor speed control for those that wanted. It did provide regen. But not elegant by any means. 

Get an AC motor if you NEED regen. Not likely you NEED regen. You may want it but don't need it.


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## wilkes5 (Jun 1, 2012)

so regen isn't really worth it in such app?


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## wilkes5 (Jun 1, 2012)

1) is it easy to find an industiral motor which can do "144 volts-800+ amps"?

2) do industiral motors need to be "rewound" before using? 

3) can industiral motors use off the shelf controllers?


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## onegreenev (May 18, 2012)

wilkes5 said:


> so regen isn't really worth it in such app?


Not with a DC motor and not with the old Military Starter/Generator style motors unless you use the old contactor style setup. 

If you want Regen then its best to go with AC. There are truly few AC systems that are affordable unless you can build your own but that will take a bit of time and effort and most likely the ability to build a rocket. 

Now with DC things are different. You CAN mix and match and you can find suitable motors from old full sized electric forklifts. Has been done for a long time or find some used one. 

Best thing if you can is to buy an old but still good system that has been abandoned from someone else for cheap then fix it up with new batteries and clean up the car and go have fun. In many cases finding old but functional electric cars are a very viable way to get into electric cars. 

I build one, Rebuilt a second conversion to a better electric and the person who purchased it from me did the same as well. I have put together another Bug and going to put it not another. I will then do the same to by old 67 VW Panel Bus. By far the easiest was reconverting the MG Midget I called Midge.

It lives its life with Frank in Colorado. It has exellent range now. I sold it with the Motor/Adaptor and installed and a contactor, fuse, throttle, RPM sensor. So he got alot and replaced the controller and batteries and charger. Simple and way cheaper than starting from scratch. 


Think about that.


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## wilkes5 (Jun 1, 2012)

always have wanted AC because of the telsa

well..it's pretty easy to buy the AC-50 kit for around $5000 dollars, then a custom battery pack for like $6000, then the guages/etc, and be done. Assuming installing everything is easy. Is it just plug and play with the kit? Adaptor plate and over with, right? 

Or just take you donar car into a place and have the guys do it for you? $$$$$

But me, was hoping for a twilight zone miracle (like the old time tv show), like picking up one of the adbundance of industrial used AC motors for sale, matching it up to a controller (off the shelf, used, but still MADE IN USA), and go with deep cycle batteries (because you can get made in usa) and have a range of 10 miles tops for around town until the custom pack (which should be dropping in price? and hope for a US manufacturer).

but, not sure about industrial


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## mizlplix (May 1, 2011)

There is a common belief that an off the shelf 3 phase motor is usable in an Ev as is. 

They can be made to run, but the wiring is of too small of a gauge to really be satisfactory.

You will need to use enough batteries to get 240 volts or above. 

Then, Get a controller that supports this high voltage. (The affordable Curtis models will not). 

Then be really careful with them because the input/output leads are really too small to handle EV currents for very long.

OR:

have the motor rewound for 120 volts and higher currents. $500-$800

Then you can use a domestic curtis controller. $100 used t0 $2000 new

Use a 125 volt pack. 10 SLA batteries @ 225AH and maybe 20 realistic mile range. $2000

For a total conversion cost of $5000 if you are really careful.

(I am sure others will want to fine tune my estimates for you.)

Miz


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## wilkes5 (Jun 1, 2012)

mizlplix said:


> There is a common belief that an off the shelf 3 phase motor is usable in an Ev as is.
> 
> They can be made to run, but the wiring is of too small of a gauge to really be satisfactory.
> 
> ...


Looks finding a good used EV motor would be best? Good price for one used, 40 hp and a above, made in USA AC motor? thanks


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## Ivansgarage (Sep 3, 2011)

Wilkes If you are willing to do a lot of work, finding a motor from a motor
shop, cleaning it out, 20 hp would be great, you would be looking at 35-40
hp continuous, 80-100 hp peak. A motor shop would wind one for about 500 bucks, and using the Curtis controller 1238-6501 about a 1000 bucks. Looking for ideas, check out my web page.


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## Tesseract (Sep 27, 2008)

Ivansgarage said:


> ...20 hp would be great, you would be looking at 35-40 hp continuous, 80-100 hp peak. A motor shop would wind one for about 500 bucks, and using the Curtis controller 1238-6501 about a 1000 bucks. Looking for ideas, check out my web page.


I agree that for the Curtis 1238 controller (which maxes out at about 74kW*) you would want to pick a 20-25kW motor as you can "overpower" the typical ACIM by 3-4x.

But I leave it to the reader to determine whether this is practical advice by looking at the specs for a typical industrial ACIM. For one example, here is link to a Baldor inverter-duty blower-cooled 25hp motor. Note that it weighs 415#... 


* - according to the "2 minute" rating in the Curtis datasheet... which also says you can't use any old motor with it, anyway, so this is kind of a moot point...


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## Ivansgarage (Sep 3, 2011)

Tesseract said:


> I agree that for the Curtis 1238 controller - which maxes out at about 74kW* - you would want to pick, say, a 20-25kW motor as you can "overpower" the typical ACIM by 3-4x.
> 
> But I leave it to the reader to determine whether this is practical advice by looking at the specs for a typical industrial ACIM. For one example, here is link to a Baldor inverter-duty blower-cooled 25hp motor. Note that it weighs 415#...
> 
> ...


Tess thats a castiron monster 25 hp I was talking 20 hp aluminum
like this 210 lbs big difference..
http://ivanbennett.com/ev-motor_20.html


------


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## mizlplix (May 1, 2011)

> * - according to the "2 minute" rating in the datasheet... which also says you can't use any old motor with it, anyway, so this is kind of a moot point...


This quote went over my head. are you referring to the Baldor motor or the Curtis controller?

thanks, miz


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## Tesseract (Sep 27, 2008)

Ivansgarage said:


> Tess thats a castiron monster 25 hp I was talking 20 hp aluminum
> like this 210 lbs big difference..


Sure, your motor was probably designed for servo applications, hence the lighter aluminum frame (or it's European). The reason I provided a link to a heavy cast-iron motor in a standard NEMA frame is because that is the type that you are most likely to find used or as surplus.

I did try to find a catalog listing for an ac induction servomotor to contrast that with the cast-iron Baldor, but the only ones I am somewhat familiar with are made by ABB and their site doesn't let you link to a specific motor.

That said, you can't drive any old motor you find with a Curtis 1238, anyway, unless you manage to convince Curtis to modify the firmware for you.


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## Tesseract (Sep 27, 2008)

mizlplix said:


> This quote went over my head. are you referring to the Baldor motor or the Curtis controller?
> 
> thanks, miz


That's what the Curtis datasheet for the 1238-6501 says. 

Just for reference, you multiply the RMS phase current by 3^0.5 (~1.732) and divide the DC input voltage by 2^0.5 (~1.414) then multiply the results of both calculations to get the power rating for an AC inverter. 

W/r/t to the 1238, specifically, if the actual input voltage is 96VDC then the AC output voltage per phase should be ~68Vrms. Curtis says the "2 minute" rating for the 1238-6501 is 73.6KVA, which then implies that the 2 minute current rating is 625A. Or perhaps the 2 minute current rating is 650A which implies that the AC phase voltage is 65Vrms.


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## mizlplix (May 1, 2011)

(Without starting an AC VS DC war)

The same can be generally said for DC controllers too. Sepex, Shunt, series.....
all have a distinct controller.

All I know is this: Quoted from the Curtis manual...



> • Curtis Auto-Tune function enables quick and easy characterization of the AC motor without having to remove it from the vehicle. Curtis AC controllers are fully compatible with any brand of AC motor.


But, I agree an off the rack AC motor will not run too well with the 1238 series controller. You need a motor built for an EV application. Or at least rewound for it.

miz


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## Tesseract (Sep 27, 2008)

mizlplix said:


> (Without starting an AC VS DC war)
> 
> The same can be generally said for DC controllers too. Sepex, Shunt, series.....
> all have a distinct controller.


Sure, but please note that I didn't make a comparison between AC and DC systems, either. 



mizlplix said:


> But, I agree an off the rack AC motor will not run too well with the 1238 series controller. You need a motor built for an EV application. Or at least rewound for it.


Yep, and the Curtis website also says that the motor has to be rewound for 15-50Vrms, which more or less eliminates every AC induction motor that you are likely to find surplus/used as they will almost certainly be wound for 208Vrms or higher.


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## Ivansgarage (Sep 3, 2011)

Tesseract said:


> Yep, and the Curtis website also says that the motor has to be rewound for 15-50Vrms, which more or less eliminates every AC induction motor that you are likely to find surplus/used as they will almost certainly be wound for 208Vrms or higher.


Tess could you tell me the link where you found the info for the
15-50Vrms Curtis. It would be a big help.


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## Tesseract (Sep 27, 2008)

Ivansgarage said:


> Tess could you tell me the link where you found the info for the
> 15-50Vrms Curtis. It would be a big help.


First entry on the Curtis FAQ page.


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## wilkes5 (Jun 1, 2012)

Ivansgarage said:


> Wilkes If you are willing to do a lot of work, finding a motor from a motor
> shop, cleaning it out, 20 hp would be great, you would be looking at 35-40
> hp continuous, 80-100 hp peak. A motor shop would wind one for about 500 bucks, and using the Curtis controller 1238-6501 about a 1000 bucks. Looking for ideas, check out my web page.


 
Lifesaver. Very nice site. Easy step by step info with pictures. More than likely be refering to it if ever build an EV. Maybe a real servie to DIY EV community? Thanks


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## wilkes5 (Jun 1, 2012)

Trick is going to be finding a good AC motor, which possibly needs a rewound, and pair it with a Curtis controller?

Can you guys simplify matching motor specs to the 1238 curtis controller?

Specs to match up

1)Volts
2)Amps
3)Continus
4) Vrms 

Do know the specs to match, just guessing.

So, pretty clear on the 15-50 Vrms spec. Funny. Matching everything else? Are you sure 20 Hp AC industiral will pump 35-40 Hp? Now getting greedy, why not pick a 30 or 40 Hp motor or will the 1238 not handle it? 


Places near southern Ohio which would rewind a motor? Just give the specs of the controller and tell the guy to rewind the motor for such? 
thanks


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## Ivansgarage (Sep 3, 2011)

wilkes5 said:


> Trick is going to be finding a good AC motor, which possibly needs a rewound, and pair it with a Curtis controller?
> 
> Can you guys simplify matching motor specs to the 1238 curtis controller?
> 
> ...


Yes the 1238 will handle a big motor 30 hp take a look at Kevins truck. This is a
full size pickup. I went by Kevins motor shop and spent a few hours talking
with him, and went for a ride in his truck, this convinced me on the Curtis controller,
and to start designing my own ev motors.

http://topekaelectricmotor.com/electric-vehicles/ac-project

A 30-40 hp motor is way to big 400-500 lbs. You need to check out
the specs on the ac-50 it started out being a 7.5 hp motor vf rated
motor. A new motor wind should be wound for 70 volts rms with lots
of wires (in hand) to handle the high amps. I will be making a video
in the next few months on hand laying a (motor winding) its not that
hard to do. I like the curtis controller, haven't heard anything bad about
them, american made.


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## wilkes5 (Jun 1, 2012)

so, stick with an industrial type motor of around 20 hp (because higher HP is too heavy), then do a rewind explained on the site. with the rewind, the industrial 20 hp motor will have like 30 or 40 hp. hook it up to the curtis 1238 and it's over (will any 20 hp motor work with an EV application or are certain motor specs needed)? it's easy like such, would love it for all enternity. too good to be true? 

scared it's not enough to make the car move sporty, or even climb hills well compared to the AC50 with like 67 hp. or have the monster AC75 to hot rod in. do you know if the industrial motors can loose the housing which probably weighs a ton? maybe it would expose the motor too much? fabricate an aluminum box to house it in (maybe vented up top with the hole for the shaft). simple.

thank you Ivansgarage for the simplicity. looking forward to jumping in on something now with the site.


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## major (Apr 4, 2008)

wilkes5 said:


> too good to be true?


Yep, that's right. 

Some guys on the forum talk about doing this AC motor rewind and inverter build or hack of industrial VFD, but they have yet to be successful with regards to a full size EVcar. It can be done, but it is far from easy. Unless you know what you doing (as in having a day job in the motor drives industry), you will be a lot better off taking the path more often traveled for the DIY EVcar.


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## Ivansgarage (Sep 3, 2011)

wilkes5 said:


> so, stick with an industrial type motor of around 20 hp (because higher HP is too heavy), then do a rewind explained on the site. with the rewind, the industrial 20 hp motor will have like 30 or 40 hp. hook it up to the curtis 1238 and it's over (will any 20 hp motor work with an EV application or are certain motor specs needed)? it's easy like such, would love it for all enternity. too good to be true?
> 
> scared it's not enough to make the car move sporty, or even climb hills well compared to the AC50 with like 67 hp. or have the monster AC75 to hot rod in. do you know if the industrial motors can loose the housing which probably weighs a ton? maybe it would expose the motor too much? fabricate an aluminum box to house it in (maybe vented up top with the hole for the shaft). simple.
> 
> thank you Ivansgarage for the simplicity. looking forward to jumping in on something now with the site.


You need to look a little closer at the ac-50 it started out as a 7.5 hp
motor, it is ONLY rated at 15 hp CONTINUOUS.. With ?? 70 hp peaks..

A 20 hp, like the one on my web site (bucket list motor) you would be 
talking 35 to 40 hp CONTINUOUS.. 80 to 90 peak..

A motor shop is the best place to find a motor NOT flea bay..
But make sure if it is burt out that the iron is not burt, just the windings.
Look for motors that were on a pump.

What to look for.
1--20 hp maybe with a vf rating, it would have a longer stator, about
7 inches in lenght. Yes you want the longer stator.

2--2 pole 3450 rpm, motors are likely to have more back iron.

3-- 208, 220, 440 volt, or just 208, 220

4--aluminum housing, motor weight would be about 225 lbs

5--C face (pump motors)

6--totaly enclosed fan over, that gives you a tail shaft for the encodder.

7--should have 48 SLOTS to do new rewind 4 pole. Just incase you find some odd ball.

If i was you, dont tell the motor shop what you are doing, they will think
you are nuts and tell ya it will NEVER work.

That should get you started.


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## wilkes5 (Jun 1, 2012)

Feel if it was common knowledge how to pick motors and such, more people would DIY convert. Feel with all the industrial motors, a huge resource for DIY EV'er community. 1000-2000 (at most) bucks for something which is green and cheap is great. Feel some might want it not to be (money or evil reasons)

Think we have all which needed to answer the thread topic, although it should probably be changed to....

"*What type spec industrial motor is needed for 3000+ lbs car with manual transmission*?" or can it be direct drive? 

answer.....

*1--20 hp maybe with a vf rating, it would have a longer stator, about*
*seven inches in lenght. Yes you want the longer stator.*

*2--2 pole 3450 rpm, motors are likely to have more back iron.*

*3-- 208, 220, 440 volt, or just 208, 220*

*4--aluminum housing, motor weight would be about 225 lbs*

*5--C face (pump motors)*

*6--totaly enclosed fan over, that gives you a tail shaft for the encodder.*

*7--should have 48 SLOTS to do new rewind 4 pole. Just incase you find some odd ball.*



Note** easy to find AC industiral motors MADE IN USA, and the Curtis Controllers seems like are MADE IN USA also..

Thanks again Ivan. Now if only a US manufacturer of good lithium battery packs existed.


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## mizlplix (May 1, 2011)

There are at least 5 separate people I know of rewinding motors at present.
Keep watching the forums and reading threads about AC motors to keep up on how they are doing in their motor projects.....

If it were easy, everyone would be doing it. Asking in a normal motor shop is a waste of time as they will tell you it is impossible. They do not have any EV experience and will persuade you to forget it.

As Major said, few have any success yet....

Ivan is the only one, so far as I know, to do one and have it run normally and as intended. He used to work in a motor shop years ago and has a really nice shop which is a distinct advantage over most people. 

A core motor can cost about $100 from a local motor shop. It would need to be about 20HP, 3 phase, 2-pole (rewound to 4 pole), inverter duty (for a longer stator), aluminum housing (TEFC usually), an old pump motor ( has a "C"-face).

As stated: The AC50 is a rewound 7.5HP inverter duty motor. It has a continious rating of 15HP. peak (for 3 seconds)of 73HP. 

Ivan's ideal motor would be twice the rating of an AC50 (and maybe a bit more). It would be 1/2 the cost or less.

Yes, The Curtis 1238 controller is capable of a lot more than the AC50 can do. It is a dependable, well built, domestic unit. It is fully adjustable to suit a wide range of motors. I see them for sale (used in the $1000 range) maybe 2-3 times per year, which might change once the new higher voltage model comes out. Otherwise they are in the $2,000 range.

The controller is a whole different animal. I would not even begin to DIY. Converting an existing industrial drive to suit an EV presents so many redesign challenges as to be silly. (As stated, unless you work in that industry).

I am sure to get arguments on that but, getting a motor to turn over on the bench and getting one to run in a normal, controlled, smooth manner in a car is two different things. 

Have any of you out there "scratch built or converted an AC inverter/controller, mounted it in an EV and drove it for 1 year without any mods or repairs at all? 


Miz


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## piotrsko (Dec 9, 2007)

wilkes5 said:


> Thanks again Ivan. Now if only a US manufacturer of good lithium battery packs existed.


There are US manufacturers. Those batteries are just very EXPENSIVE.


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## major (Apr 4, 2008)

mizlplix said:


> As Major said, few have any success yet....
> 
> Ivan is the only one, so far as I know, to do one and have it run normally and as intended.


Hi miz,

So has Ivan got any load data to share with us on his rewound motor? Or actual "in vehicle" performance?



> Have any of you out there "scratch built or converted an AC inverter/controller, mounted it in an EV and drove it for 1 year without any mods or repairs at all?


Eric is about the only one. He did a nice job. He appeared to have been very familiar with VFDs and even then blew up some silicon in the process. But final result is impressive. Now the guy works for Tesla...go figure  
http://www.diyelectriccar.com/forums/showthread.php/converting-2001-passat-15363.html 

And the subcooledheatpump guy did one for his van, but I don't think it lasted a year.

I've done a number of them over the years but have been for performance vehicles, not the street conversions. So I know the difficulty level and don't even attempt to walk a DIY through it.

All this relates to the reason for my post #36. The typical newcomer to this DIY forum should not be encouraged to pursue this approach IMO. It is likely to end badly for him. If he wants to use AC, go for a motor/controller package where he will have dealer support. If that is beyond his budget, then go with the DC.

Regards,

major


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## MN Driver (Sep 29, 2009)

piotrsko said:


> There are US manufacturers. Those batteries are just very EXPENSIVE.


Don't forget that they aren't just expensive, they are unobtanium as they don't want to have their product in the hands of consumers but rather in a completed product owned by an OEM who provides the customer support.

I can't think of one example of a US made LiFePO4 battery that we can buy easily and get the level of support we get from CALB or what we got from TS. Mavizen/A123 really doesn't want to have anything to do with us.


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