# DC Motor. No Flames, Just Facts Please



## Sunking (Aug 10, 2009)

I see a lot of GE Electric Motors advertise here from what look like a robot posting. I do not care about the Robot News, All I care about is the Specs or lack of them.

Can anyone determine what they are really capable of like this one>

Here is the deal I want to find a DC wound motor made for a EX-GO 12 spline Axel. I want acceleration tree climbing torque to get off the starting line, but some RPM to get 30 MPH or better.

Better yet I want bragging rights in my gated golf golf cart 1/8 mile drag races we have on Memorial Day, Labor Day, and end of year holidays. All for bragging rights. 

Thought I had it all figured out using a GE 282 Raptor motor, with 500 amp controller. Blew everyone off th line with a wheelie, tire barking, and top 30 MPH speed in 30 feet. 

This this jerk pulls up in a standard factory cart made by EVE called a Farplay. Please take a look at it the specs are awesome,

He is really a nice guy and blew my doors off. It is actually a NEV made for golf communities. This thing has all the Bells and Whistles of a real car like bucket seats, built in ice chest, and trunk, lights, horn, turn signals. independent suspension, 4-wheel disc brakes, and looks really nice. 

Mine is all stripped down to race, right down to 4 lightweight batteries. I blow him off the line, but half up the track he pulls up to me, slows down, and offers me a beer. Then leaves me behind in a cloud of dust wating at the finish line drinking beer..

After many bears and looking under the hood, the only mod he claims to have made is program the controller lifting th 35 MPH limit which gets him 40 MPH.

Guys only thing I see he has under the hood is a AC motor, decent controller/inverter, and 4 Trojan AGM batteries. The pisser is it is factory stock, cost $8000. I go that much tied up in my buggie.

How can I beat this guy? Just join hi and buy one then tinker with to get that extra mph or 2 on the top end? AC motor seems to be the trick.


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## EVfun (Mar 14, 2010)

Well, 500 amps seems to be the current required to make the torque to run away from him. You just need to continue the power band to higher rpms. The answer to that, with a series motor, is more voltage. Perhaps 6 Optima batteries and a 72 volt, 500 amp, controller. The higher voltage will carry your power band up to higher speed. 72 volts will extend the launch torque band up from about 30mph to about 45 mph. Make sure you have the brakes and room to stop it! 

Roderick from EVparts has some experience with over-volted golf cart motors and they seem to take it. I rode is a wheel-standing power-sliding monster of he created. In a quick glance I don't see any inexpensive options in that range perhaps an Alltrax AXE 7245, 72 volt 450 amp controller. The loss of 50 amps would cut launch a little, perhaps you have some to spare?

I'm sure it could be done with AC too, but I have no experience with AC conversions.


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## Sunking (Aug 10, 2009)

EVfun thanks, but I am already aware of going up to 60 or 72 volts. Problem is I do not think, or I should say I do not know if the motor can safely handle the extra voltage and RPM. 

All the golf cart motors I see, do not come with any useful specs.


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## EVfun (Mar 14, 2010)

You can kinda create your own specs. First check out the gearing as you don't want the motor over 6000 rpm, you may have to limit speed to hold rpm down. Most smaller diameter motors can take 6000 rpm (less for 9 inch and above.) Next, count the exposed commutator bar slots (the spaces between bars) between 2 brushes. You almost certainly can take 20 volts time the number of open slots. You can often push upward to 30 volts per open slot with increasing risk of burning up the motor.

If you post the motor name plate data here someone may have some direct experience with the motor or even a spec sheet. I'm not getting useful data googling "GE 282 motor."


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## piotrsko (Dec 9, 2007)

I'll bump in here to post the old racers caveat: if you are afraid of breaking something then you didn't push it hard enough.

JOKE >>> I suggest a 11 kostov, a solitron 1 and perhaps 300 v worth of lithium.

the new problems would be then traction and keeping it on the ground.

seriously, you need to look at the physics of what you are trying to do with this racing.
GE 5BC49JB1127 motor 7 hp 48 v probably 300 amps for a short while which would be 40 ish horse.


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## Sunking (Aug 10, 2009)

EVfun said:


> If you post the motor name plate data here someone may have some direct experience with the motor or even a spec sheet. I'm not getting useful data googling "GE 282 motor."


There in lies the problem, the specs. Here are some:

GE D398
Club Car 
EZGolf
CartZone D398

There is just not there to work with. Maybe I am crazy and breaking away fro golf cart motors and thinking may one of the WARP series motors, but that sound like a step in my limited mechanical skills to fabricate an interface plate.

Just about convinced to trade in my two carts and buy a Fairview cart, change the battery pack with Life4pO pack to lighten the load and reprogram the controller.

Open to all ideas.


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## EVfun (Mar 14, 2010)

In the end power is power. The cart you're up against has 48 volts at 500 amps unless it has been altered past the posted specs. I don't know how your cart compares to it in weight but at the end of the day you need a better power to weight ratio than him and the ability to reach a decent speed (more voltage, taller gearing) so it doesn't fall flat.

Why do you need to look at different motors? If you are willing to spend the money on another then you can push the one you have. Worst case you 'get' to buy a new motor anyway. Give the stock motor a brush and commutator tune up and up the voltage and amperage. Series wound DC motors don't have ridged ratings. You can exceed the listed voltage and amperage without poof, the farther you go the shorter time you can spend there so you best plan to get to speed quickly. 

Speed controllers don't have that tolerance for the most part, they won't give you more amps than they are rated for or survive more voltage than their nameplate. So a higher voltage pack and a suitably rated new controller will give you more power without changing other things. You should check the ratings of other parts, the DC to DC converter if you have one and the main contactor. You will need a suitable charger for whatever pack you choose. 

AC may give him some advantage, mostly a little broadening of the power band because commutation is handled in software and can be tweaked on the fly. Still, 48 volts and 500 amps is not going to make more than about 26 horsepower. No one is getting more than 1 horsepower for each 746 watts and no motor/controller package is 100% efficient so it will always be less than that.


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## E4mula (Mar 31, 2009)

As stated, your power is comparable to his, the difference being your gearing. You've got more torque to the ground but run out of rpm. So change the gearing/tire size or increase the voltage and you'll be able to keep up with him. Do both and pull ahead.
As EVfun said, when increasing voltage make sure that all components can handle it


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## Sunking (Aug 10, 2009)

E4mula said:


> As stated, your power is comparable to his, the difference being your gearing.


Well I understand what your are saying, not sure I completely agree. I am running a series wound DC motor, and he is running an AC induction motor. I got gobs of torque at 0 RPM up to maybe 1000 RPM, then peters out up to guessing at say 5500 RPM at 48 volts fully applied. So my max HP is at half voltage-RPM

Although he does not have my kind of torques at low RPM's his stays constant up to say some point unknown to me. 

I can increase the size of the tires even using a lift kit to accomplice that. (I have that much mechanical ability), but transmission gearing is out of my scope.

So my question back at you is what will changing the controller to a higher voltage, upping the batery voltage from say 48 to 60 volts buy me if my motor torque is done at 5300 RPM at 48 volts? I am missing something?


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## E4mula (Mar 31, 2009)

> So my question back at you is what will changing the controller to a higher voltage, upping the batery voltage from say 48 to 60 volts buy me if my motor torque is done at 5300 RPM at 48 volts? I am missing something?


Yep, increasing the voltage will increase the rpm that your torque starts to drop off. Do a search on 'back emf' if you want to find out why.

If you're already over 5000 rpms, it may not be safe to increase the voltage any further.
In that case, go with bigger tires and a higher current controller to keep your acceleration rate.


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## rmay635703 (Oct 23, 2008)

E4mula said:


> Yep, increasing the voltage will increase the rpm that your torque starts to drop off. Do a search on 'back emf' if you want to find out why.
> 
> If you're already over 5000 rpms, it may not be safe to increase the voltage any further.
> In that case, go with bigger drive tires and a higher current controller to keep your acceleration rate.


Yep, bigger tires reduce RPMs, sadly they also disproportionately increase amp draw because they don't spin as easy. More air pressure helps that matter.

My 6 3/4" 5hp motor in the ZX40 is rated at 6300rpm's continous, sadly many manufacturers don't list that number or list it inaccurately, if the motor is readily available and cheap, rev it up and see. some little motors will do 10 grand, others fall apart at 5k rpms depending on how they are built.

Good Luck


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## Sunking (Aug 10, 2009)

E4mula said:


> If you're already over 5000 rpms, it may not be safe to increase the voltage any further.


Well we have come full circle which is what the original point of this thread was if anyone had a clue where to find the specs. 

All I know is the motor is rated 3900 RPM's @ 36 volts and 5300 @ 48 volts. I do not know how much further I can push it.


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## Roy Von Rogers (Mar 21, 2009)

Sunking said:


> Well we have come full circle which is what the original point of this thread was if anyone had a clue where to find the specs.
> 
> All I know is the motor is rated 3900 RPM's @ 36 volts and 5300 @ 48 volts. I do not know how much further I can push it.


 
Isnt it fun to be in a place were DYI are welcome and are helped ???

Not like some other forums were your told that your working with dangerous voltages and you can burn your house down, not to mention that you may be taking someones bread off the table.

Roy


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## rillip3 (Jun 19, 2009)

Sunking said:


> Well we have come full circle which is what the original point of this thread was if anyone had a clue where to find the specs.
> 
> All I know is the motor is rated 3900 RPM's @ 36 volts and 5300 @ 48 volts. I do not know how much further I can push it.


That information is just not available from the manufacturer. As EVFun said, you're already looking at buying a new motor. Why not advance the motor, and if it dies, big deal, you were looking at getting a new one anyway right? Either that, or get a motor that you can find more detail specs on so you know what you're working with.


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## Renny_D (Apr 21, 2009)

I'm selling a 72 volt controller and charger. It's the Altrax 72 volt 450 amp controller and a Delta q charger. 700 for both or 400 for either. With that and a few hawker genesis batteries you'd smoke him. You may have problems stopping though.

Let me know if your interested.

Renny


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## rmay635703 (Oct 23, 2008)

rillip3 said:


> That information is just not available from the manufacturer. As EVFun said, you're already looking at buying a new motor. Why not advance the motor, and if it dies, big deal, you were looking at getting a new one anyway right? Either that, or get a motor that you can find more detail specs on so you know what you're working with.


Generally manufacturers don't want to bother with hi speed operation because in the past too many of their motors would fail, some would not but too many would so they quit the practice of rating them in the 8000rpm area and always stuck with 5000rpms.

Its not that every motor would fail at 8k, its that some would fail after a while, while others would not.

I encountered this same problem with both my Jianjin and D&D motors, the company may have some information but they will not release it.

Cheers 
Ryan


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## vpoppv (Jul 27, 2009)

Fwiw, when I was researching my motor, I came across this:

http://server1.buggiesunlimited.com/phpBB2/viewtopic.php?f=11&t=2816&hilit=baldor

Basically, the guy ran the same 2hp, 36v, 53 amp max, 45 lbs Baldor motor I have at 96v for a year, then fried it at 120v. He rebuilt the motor and took it to 168v. Top speed he says is 50mph and that the limiter was the rear end. Bottom line is it seems golf cart motors can take a beating. Mine seems ok at 72v with probably twice the weight a golf cart. Could blow up tomorrow. But you only need it for one race, right?


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