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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. Correct me if i'm wrong on these.
Hi suk,

Not bad :) Here's a couple of comments. Refer back to your #1 post for quote context.

(36V usually is too low)
Not necessarily. Many 36V motors work out well for guys on 72 or 96V systems, some even higher. That usually requires advance (shifting the brush position).

A heavier one is o.k. but it limits your range
Unless you go way overboard, I doubt you need to worry about a few motor pounds subtracting from your range.

Hp from an electric motor is not the same as Hp from an Gasoline engine
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 :)

Regards,

major
 

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OK, I'm a Noob. I have an industrial electric motor that is rated at 10HP, 240V A/C 3 Phase. It weighs a heck of a lot, well over 100 lbs.

I also have a 10KW generator, again 3 phase and 240 volt. (This thing weighs a TON!!!!)

How would these two motors compare to one another and would either of them be suitable for an electric conversion powerplant?
Hi Vik,

One is likely an induction motor and the other an alternator (synchronous machine). Neither would be a good choice for a rookie EV builder. AC motors require inverter type controllers typically costing more than DC converter controllers. Standard 240VAC machines mean battery pack voltage on the order of 300VDC. This increases the cell count, and cost of associated equipment for the battery like management and charger.

Regards,

major
 

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Is it possible to use a power converter to 110 ac and use a 110 electrict
motor
Short answer....NO :(

I suppose you're talking about those 12VDC to 110VAC inverters sold to run AC stuff from your car battery. Those mostly are not sine wave and are single phase. For EV propulsion motor, you need 3 phase, and variable frequency on top of that.

Other issues also ;)

major
 

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Rich or poor, if you want reverse, I think you should invest in a controller that has reverse capability.
With series motors reversing is accomplished with a contactor set not in the controller. Or some lower voltage/power systems like golf carts will use a manual multipole selector switch. Here is how it looks in the circuit:


Ref: from the Curtis manual.
 

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Thanks Major. Would you suggest using a contactor or manual switch without a controller?
I don't understand the question. You need the controller for speed control. The reversing contactor (or switch) is outside the controller. The manual type of reversing devices may not hold up well with voltage in excess of 48 or with currents exceeding 200 amps regularly. And they are a PITA to string large cables to where you can reach them. Reversing contactor sets can be located near the motor and controller and activated with a signal switch. Contactors also come in higher voltage/current ratings.

I don't suggest running any motor (in an EV) without a controller.
 

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The industry standard for marking the terminals on DC motors used in forklifts, industrial utility vehicles and golf carts in the United States was and still is, I believe, as follows:

A for Armature (connected internally through the brushes),

S for Series field coils,

F for Shunt or Separately Excited field coils.
 

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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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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?
 

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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.).
 

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Those look like nice motors, but the max speed is a bit low and the rated voltage is a bit high. From what I can tell, these were installed in-line with the driveshaft on the hybrid trucks/vans/busses that they came from, so 5000rpm is probably plenty for that. A rebuild of one of these with a high speed balance and some good bearings would probably make for a very nice motor. I can't tell if they're water cooled or air cooled. It looks like there might be a hose poking out in one of the photos?
Hi big,

Those were made by Lincoln Electric in Cleveland; a NEMA 286T frame. We used one for a project and balanced the rotor and used precision oil lubed bearings and did well over 10,000 RPM, 12k peaks. With modified windings, 350Vdc bus and liquid cooling, it was capable of over 200kW. Those pictured are TENC (totally enclosed non-cooled). And I think the Azure application was limited to like 400A-phase (for member dcb).

Those are real nice motors--- big but nice. Great extruded aluminum frame shell. A shame they used iron end caps. We had aluminum ends made for ours.

Regards,

major
 

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Hi.
Would be nice to get some input on using this Fanuc 10 M dc servo motor to power a light weight Opel Corsa. Theyt apparently have high torque since they are used in Cnc lathes etc. The motor is about 30 years old but was never used.

Any advice would be appriciated.
Thank you.


View attachment 106818
165V * 12A = 1980W or about 2 hp by the time you get to the shaft output.

I doubt you'll be happy with a 2 hp powerplant in a car.

Regards,

major
 

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Hi Guy's

Do you think a hydraulic motor from a Lansing Bagnal Forklift rated at 67v and with the part number 4005679, Series wound continuous, would be a suitable EV drive motor?

regards John
Hi John,

I assume you mean a pump drive motor. Hydraulic motor typically refers to a device using hydraulic fluid flow to produce a mechanical output.

Contrary to what was told you on the other thread, main (lift) pump motors from fork trucks can be as powerful, or even more so, than traction motors. It depends on the type of lift truck. Just because the pump motor is rated on a low time-on duty cycle doesn't mean it won't run continuously, at a lower power output. And they are often fan cooled.

The pump motor from a forklift may be suitable for an EV conversion. Typically they are unidirectional, so be sure rotation direction is correct for you. Switching rotation requires internal modification. And typically the motor will have an internal splined shaft making a coupling for a car very difficult.

Regards,

major
 

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Hi john,

From that info, I'd say it is a split field reversible series wound motor. The typical reversible series wound motor has 4 terminals, A1 & A2 for armature and S1 & S2 for the series field. Reversing is accomplished by reversing one or the other, but not both. This requires heavy (full motor current rated) contactors, two spdt. Read expensive.

The split series motor is actually designed and built with two independent (electrically) field coil sets. One coil set (Y) for one direction of rotation and the other coil set (YY) for opposite rotation. Now it can use a single spdt contactor or two spst. It does require additional diodes. This can be a cost savings. However you pay a penalty in series field resistive loss, perhaps affecting motor efficiency ~5%.

There are some other tricks designers can employ with the split series motor which can eliminate the reversing contactors altogether, do field weakening, and/or motor braking even with some degree of regeneration, when mated with a specialized controller.

Testing is the easiest method to verify what you have. Use a 12V car battery and jumper cables or the like. Put motor on floor or otherwise clamp it so it does not twist off the bench onto your toe. Connect one battery terminal to A. Connect (touch) the other battery terminal to Y. Note rotation direction. Leave A connected the same. Now touch other battery terminal cable to YY. If rotation is opposite, it is split series.

If rotation is the same, likely it is a tapped field. See if you can detect a difference in speed between the two connections.

Regards,

major
 
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