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Finding a motor on a budget

286318 Views 173 Replies 62 Participants Last post by  piotrsko
So here is what I learned about motors from this site. I wanted to post a quick reference so newbs (like myself) do not have to sort through the sticky page.

When looking for a forklift motor:
Get a series wound motor because they have very high torque and handle abuse (over volting) a lot better.
Know the difference between a Spex motor and a Series wound.
When dealing with series wound forklift motors go for higher voltage. (36V may require advanced timing.)
Hp does not directly represent torque (although it does have a factor in its equation).
Get a class H insulation if possible (makes your motor last longer)
Get a motor around 150lbs (Wouldn't risk a motor that's too light, it won't have the oomph you need. a few extra pounds is A-o.k. but a significant amount of extra pounds limits your range)
Get one with a male shaft
A keyed shaft is easier to work with but you can still work with a spline shaft
Try and get the coupler that goes on to your motor when you buy it/rip it out (saves you $$ and time)
When looking for a different motor:
Ac is not the way to go for your first conversion (or do i just have low expectations of myself?)
You can tell if a motor is AC if it is a 1 phase or 3 phase motor
Pancake motors are usually not good candidates for car conversions. (Yeah you saw the one on ebay. They overheat easily)
Golfcart motors are seldom powerful enough for a conversion
Motors specifically made for EV conversions are the best but its gonna cost you.
You do have to look at many factor such as volts, amps (which gets you Hp). Torque is nice to know. Continuous Hp. So many factors!!!
"HP is HP Electric motors and gas engines are rated differently w/r/t HP. And they have different torque curves. But one HP from an electric motor shaft is exactly the same as one HP from a gas engine shaft at the same RPM :)"- Major
If there is any more helpful hints I'll be happy to add them
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These two sentences mean exactly the same thing

" I need the in-line reactor in series with the stator"

" I need the induction coil in series with the field "
They do NOT mean exactly the same reason, which is why you will always have both. "Stator" is a mechanical designation while "Field" is an electromagnetic designation. The "Field" is the source of magnetic flux (either a magnet or an electromagnet). The "Stator" is the stationary portion of an electric machine that surrounds the rotor. For brushed DC motors, the terms are often used interchangeably, because the Field resides in the Stator (in the case of series wound brushed DC motors, the field is an electromagnet, so the stator contains field windings. PM brushed DC motors have magnets in the Stator). But in other motors, such as 3 phase AC motors or brushless DC motors, the field resides in the rotor, and the stator contains the armature windings (which are in the rotor in a brushed DC motor).

So if you are working with more than one kind of motor, the distinction is very important, so those two terms aren't going anywhere. :) Sorry it makes your life harder, but motors are complicated beasts.
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Anyone ever use or thought about using a brushed dc elevator motor? Where could I find one?
On the roof of tall buildings :) I think elevator motors are large, high voltage and probably shunt wound making them a difficult fit for EV cars.
On the roof of tall buildings :) I think elevator motors are large, high voltage and probably shunt wound making them a difficult fit for EV cars.
Warp 13 size or bigger ..... WARP 15 ???
I work for a large airline and when we scrap electric vehicles I assure all of you it's never because the motor is bad.
If its old the cost of new hoses fork blades paint seat tires brakes and the kicker a $5000 to $6000 battery is the reason to scrap.
Last month we sent 8 electric pickers to scrap because it was part of the city contract with the building, go figure!
I have a 9 inch dc advance they threw away with under 100 hrs on it because someone didn't tighten the set screw on the shaft key ill just weld the adapter on or redo the shaft if i ever get a project.
Why toss a 1000 motor cause time is money and. Sending people far away and paying for hotels out costs parts.
Fork lift motors are good also airport belt loaders and bag tugs if they are electric are good most of the belt loaders and bag tugs use dc advance 9 inch motors
http://gsemarket.com/index.htm
Used stuff some times sells for less than scrap value on this site
It has to do with tax depreciating equipment to nothing being better than scrapping it without proff of 0 value
Happy hunting
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I am glad I live in Australia and have used the Metric system for over 40 years. I find it so easy to use, and find the avoirdupois methodology a fair bit harder.
Is a 50kw motor big enough, 67,000HP to drive an electric car?
Is a 50kw motor big enough, 67,000HP to drive an electric car?
That should be 67 HP not 67,000. I think you will need to supply more info to answer your question properly. Depending on many other factors, it might or might not be. 50kw is enough to move a small car, but a power number alone is not enough. Example, I have a forklift motor that is only rated for 10kw, but that is continuous at only 44 volts. It weighs over 100kg's and, if I up the voltage, it will move a car. Others have used the same motor successfully. On the other hand, there are RC motors that are rated for 20kw that you could hold in your hand. They might power an e-bike if you were lucky. See what I'm saying?
Thank you puddleglum for your answers. Yes I had made a big mistake with the HP. Don't normally use them so easy to mess up. I am thinking of using Nimh batteries, D cell 10Ah, about 5000 of them, as the power supply for my motor. I am thinking that Nimh or maybe Lithium Ion are the most power dense batteries that are around. And maybe having 2 50kw motors or a 50kw and a 20 kw.
Hello All,

Delighted to find this portal and all the great info. So I'm planning on doing a EV, and have located a motor, and was looking for some advice before I purchase it on Ebay. It is in the $1,500 cost range. Is that a fair price for new unknown motor make/model?

See attached summary.

? is this acceptable for a EV converson? Have not decided on donor car yey, maybe VW cabriolet, small pick up, or Mazda Miata. Would really like to do convertable, maybe a jeep too. Trying to do this on a budget. Hoping for 50 mile range at minimum.

? Does anyone have a clue who makes this motor?

? Any suggestions for controllers.

? What bus voltage should i go with.

? Can i do some type or re-gen or is that too dificult with used/low cost controllers?

? Do i need tach or sensor on motor, i do not see a plug on the pictures.

? Should i go with transmission & cluch or direct to transmission, or straight to drive shaft if i go with non transaxle running gear.

Thanks for the help and advice.

Regards,

Trevor

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Hello All,

Delighted to find this portal and all the great info. So I'm planning on doing a EV, and have located a motor, and was looking for some advice before I purchase it on Ebay. It is in the $1,500 cost range. Is that a fair price for new unknown motor make/model?
Not bad. A new one would probably be twice that. A similar sized used forklift motor might be found for less.
See attached summary.
Interesting.
? is this acceptable for a EV converson?
Probably. It looks pretty nice IMO.
Have not decided on donor car yey, maybe VW cabriolet, small pick up, or Mazda Miata. Would really like to do convertable, maybe a jeep too. Trying to do this on a budget. Hoping for 50 mile range at minimum.

? Does anyone have a clue who makes this motor?
I don't think it was Prestolite like they suggest.
? Any suggestions for controllers.
The usual big boys like Solitron, Zilla, Netgain.
? What bus voltage should i go with.
Using those controllers, any battery voltage up to limit (about 400) and then limit motor voltage to 150 to 200 depending on your need.
? Can i do some type or re-gen or is that too dificult with used/low cost controllers?
Not with a series motor.
? Do i need tach or sensor on motor, i do not see a plug on the pictures.
I suggest a speed sensor. I think all those controller will limit speed for you. And it is a nice parameter to monitor.
? Should i go with transmission & cluch or direct to transmission, or straight to drive shaft if i go with non transaxle running gear.
Up to you.
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Hello All,

Delighted to find this portal and all the great info. So I'm planning on doing a EV, and have located a motor, and was looking for some advice before I purchase it on Ebay. It is in the $1,500 cost range. Is that a fair price for new unknown motor make/model?
If you are going to spend that much, why not just buy a Warp or Kostov for just a little more. They are already optimized for EV use, well proven and have a warranty. Just my opinion.
If you are going to spend that much, why not just buy a Warp or Kostov for just a little more. They are already optimized for EV use, well proven and have a warranty. Just my opinion.
Thanks, i was off on the price with shipping its 1100, and is new, so what does a warp or kostov cost? Are they ~25 HP cont? I guess i better do some more research before i pay for this unit.
Thanks, i was off on the price with shipping its 1100, and is new, so what does a warp or kostov cost? Are they ~25 HP cont? I guess i better do some more research before I pay for this unit.
$1100 shipped is a lot less than the $1500+ shipping you had posted before. Major is the motor expert, I'm NOT, but there are a few EV motors that claim 25 Hp cont. in the $1400-1800 range. I know for a fact that a new forklift motor is much more money than an EV motor of similar power and you still have to modify it. Used ones can be pretty cheap though.
Whats a cheaper replacement if any for a larger Ac motor like the AC-76?
i would like someone to help me.
i came across this motor, and i am wondering could i use it in my ev.

price: 500$
15,2 kW, 236 A, 75 V
1800 rpm na 75 V and 2300 on 96V.

it is rated for 1800 so i dont know if this 2300 is okay to run on.

if i understood correctly, this motor would give me top speed of 60kmh.(around that)

or should i put in another 500$ and take kostov 9"

help me plox :D
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i would like someone to help me.
i came across this motor, and i am wondering could i use it in my ev.

price: 500$
15,2 kW, 236 A, 75 V
1800 rpm na 75 V and 2300 on 96V.

it is rated for 1800 so i dont know if this 2300 is okay to run on.

if i understood correctly, this motor would give me top speed of 60kmh.(around that)

or should i put in another 500$ and take kostov 9"

help me plox :D
Please post some photos and/or more details. Where did those numbers come from? Can you post the source? What kind of motor is it?
Nice motor. Looks like robust construction. However it was likely used to drive a pump and therefore has a shaft which will be a bitch for you to use. Also the power rating is for S3 duty cycle of 33%, so the continuous or one hour rating will probably be one third to one half of that figure or 5 to 7kW at 72V. Raising voltage and RPM can increase the rating if good ventilation is provided. Enough for your car? Depends on the car and expected performance (speed, hill climb, payload, etc.).
Nice motor. Looks like robust construction. However it was likely used to drive a pump and therefore has a shaft which will be a bitch for you to use. Also the power rating is for S3 duty cycle of 33%, so the continuous or one hour rating will probably be one third to one half of that figure or 5 to 7kW at 72V. Raising voltage and RPM can increase the rating if good ventilation is provided. Enough for your car? Depends on the car and expected performance (speed, hill climb, payload, etc.).
thank you for your reply.
How do you know its S3? (just curious, so i know in the future)
what is downside of raising rated voltage and rpm besides higher temperature and therefore better ventilation needed?
i thought of driving ev in straight terrain (no hills or anything like that), with a top speed around 80-ish kmh, this probably wont do above 50-60 kmh the more i look. correct?
How do you know its S3?
I can see it on the nameplate. And higher voltage can sometimes cause arcing on the brushes to commutator.
Newbe here what about a splined shaft clark forklift motor 36/48volt motor on ebay? is that a good candidate for a useable motor? Thank for any help......frank l.
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