Using a forklift motor, and choosing a good one - Page 157 - DIY Electric Car Forums
Go Back  

DIY Electric Car Forums > EV Conversions and Builds > Electric Motors

Register Blogs FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1561  
Old 03-04-2012, 06:32 PM
david85's Avatar
david85 david85 is offline
Administrator
 
Join Date: Nov 2007
Location: Campbell River, Canada
Posts: 4,817
david85 will become famous soon enough
Default Re: Using a forklift motor, and choosing a good one

Quote:
Originally Posted by Dan Frederiksen View Post
david, read back and realize I am the righteous one and jrp3 and major attacked me without any reason whatsoever. they should be banned, not me. I'm the one who was really helpful. they didn't help at all.
if you want to be an administrator, be a good one
Enjoy you're vacation, Dan.

Sorry about the thread disruption, guys. If he comes back after 2 weeks and starts trouble again, just let us know and we can make it a permanent ban.
__________________
I knew what kind of vehicle I wanted to drive since before I was old enough to drive,

All I had to do was build it.. http://www.diyelectriccar.com/forums...ion-26587.html

Garage: http://www.diyelectriccar.com/garage/cars/206

Forum Rules and terms of service:

http://www.diyelectriccar.com/forums/faq.php
Reply With Quote
Sponsored Links
Advertisement
 
  #1562  
Old 03-13-2012, 03:37 PM
zsnemeth zsnemeth is offline
Senior Member
 
Join Date: Jan 2012
Posts: 100
zsnemeth is on a distinguished road
Default Re: Using a forklift motor, and choosing a good one

Hi Major,

I'd need Your help with this motor. I read the whole thread a few months back, i haven't seen anything like this here before.
This is looks like some sort of in wheel forklift motor, about 10" diameterand 14 inches long, 36V and has C.E.V. name on it. That's all i could get from the seller.
Doesn't look promising.
Is it useful?



Thanks in advance
Z
Reply With Quote
  #1563  
Old 03-13-2012, 03:53 PM
major's Avatar
major major is online now
Senior Member
 
Join Date: Apr 2008
Location: Ohio, USA
Posts: 6,453
major has a spectacular aura aboutmajor has a spectacular aura about
Default Re: Using a forklift motor, and choosing a good one

Quote:
Originally Posted by zsnemeth View Post
This is looks like some sort of in wheel forklift motor, about 10" diameterand 14 inches long, 36V and has C.E.V. name on it. That's all i could get from the seller.
Doesn't look promising.
Is it useful?

Hi Z,

Yeah, not promising. Not sure about this particular one but looks similar to some US trucks using K H Porter 8 pole short stack motors with gear heads for a wheel motor. It would be difficult to adapt such a motor for an EVcar. I think I'd pass on it unless you have an application for 3 or 4 kW slim motor. And it is likely pretty heavy for its power rating.

Cheers,

major
Reply With Quote
  #1564  
Old 03-13-2012, 04:16 PM
zsnemeth zsnemeth is offline
Senior Member
 
Join Date: Jan 2012
Posts: 100
zsnemeth is on a distinguished road
Default Re: Using a forklift motor, and choosing a good one

Quote:
Originally Posted by major View Post
Hi Z,

Yeah, not promising. Not sure about this particular one but looks similar to some US trucks using K H Porter 8 pole short stack motors with gear heads for a wheel motor. It would be difficult to adapt such a motor for an EVcar. I think I'd pass on it unless you have an application for 3 or 4 kW slim motor. And it is likely pretty heavy for its power rating.

Cheers,

major
Thanks Major, i'll keep looking.
Reply With Quote
  #1565  
Old 03-15-2012, 11:47 AM
DIT DIT is offline
Junior Member
 
Join Date: Mar 2012
Posts: 18
DIT is on a distinguished road
Default Re: Using a forklift motor, and choosing a good one

Hi,

First post here but just looking for some advice on a motor I got for our final year college project.

Would this motor power a Mitisubishi Colt that is completly stripped down and weighing about 700kg.

Thanks for your help
Attached Images
File Type: jpg 021 (1).jpg (34.4 KB, 20 views)
Reply With Quote
  #1566  
Old 03-15-2012, 12:44 PM
major's Avatar
major major is online now
Senior Member
 
Join Date: Apr 2008
Location: Ohio, USA
Posts: 6,453
major has a spectacular aura aboutmajor has a spectacular aura about
Default Re: Using a forklift motor, and choosing a good one

Quote:
Originally Posted by DIT View Post
Would this motor power a Mitisubishi Colt that is completly stripped down and weighing about 700kg.
Yes, but at what speed Not very fast. Taking it at nameplate value, it is 0,55kW at 48V, 17A. You can overload electric motors for a short time maybe 3X and raise the voltage increasing RPM and get maybe another 2 to 3 factor which puts you into the 3 to 4 kW range for very short duration unless you actively cool it. So, do you want a car with equivalent performance to that with a 5 hp engine? If you try hard you may come out with an EV which could outrun a golf cart.

Depends on your performance goals,

major
Reply With Quote
  #1567  
Old 03-15-2012, 12:48 PM
DIT DIT is offline
Junior Member
 
Join Date: Mar 2012
Posts: 18
DIT is on a distinguished road
Default Re: Using a forklift motor, and choosing a good one

Sorry forgot to say that the car will just be used to be driven around the college parking lot and small distances(.5 of a mile at a time).
Reply With Quote
  #1568  
Old 03-19-2012, 09:39 AM
Dan Frederiksen Dan Frederiksen is offline
Banned
 
Join Date: Jul 2007
Posts: 186
Dan Frederiksen has a little shameless behaviour in the past
Default Re: Using a forklift motor, and choosing a good one

major, why do you say that terry's motor is unusable over 100V? that is most certainly wrong. if your thinking is that it can overspeed then that's always a risk with series wound motors in EVs. that's true for all of them. that doesn't make them unusable. it just means you should avoid too high rpm.

you simply don't know what you are talking about.

indeed it is the case that it needs over 100V to reach its full potential in an EV.
a permanent magnet motor has a firm correlation between max rpm and voltage. series wound motors do not.
Reply With Quote
  #1569  
Old 03-20-2012, 08:02 AM
major's Avatar
major major is online now
Senior Member
 
Join Date: Apr 2008
Location: Ohio, USA
Posts: 6,453
major has a spectacular aura aboutmajor has a spectacular aura about
Default Re: Using a forklift motor, and choosing a good one

Quote:
Originally Posted by Dan Frederiksen View Post
major, why do you say that terry's motor is unusable over 100V?
Now that we don't have to worry about Dan, I will address this for others who may have wondered.

If you look back over the previous several pages, you'll find that this particular motor has a nameplate rating of 67V and 3200RPM (15 minute). We speculate it is series wound. Regardless, at the rated load, we can proportion the RPM by the ratio of applied voltage. So at 100V, RPM = 4776. This is about as fast as I would recommend; in fact, too fast, I feel for reasonable operating motor speed. Add to that, at any load less than rated, the motor RPM will increase. At current limit (say 400 or 500A), motor RPM would be less than 4776 at 100V applied, but likely still above 4000RPM which would cause commutation arcing. While that might be tolerable for a drag racer, I wouldn't recommend it for the normal EVcar.

I did mention to terryg that the motor could be used with higher voltage battery if the controller could be set to limit the voltage applied to the motor. But I don't see an overall benefit of doing that.

Regards,

major
Reply With Quote
  #1570  
Old 03-20-2012, 10:15 AM
MalcolmB's Avatar
MalcolmB MalcolmB is offline
Senior Member
 
Join Date: Jun 2008
Location: Newcastle upon Tyne, UK
Posts: 555
MalcolmB is on a distinguished road
Default Re: Using a forklift motor, and choosing a good one

Hi major
I just start to think I'm getting a grasp on the workings of these motors, then find my mental model is built on shaky ground. Can you help me understand your reasoning? I can see that this particular motor is not very suitable with its low 15-minute current rating, but I'm not sure I follow the voltage limit reasoning. I got the impression that the nameplate rating was just one datum point, often chosen for the benefit of the intended customer. The current limit is obviously fixed by the efficiency of the motor and its ability to dissipate heat. But aren't most series motors run well beyond what would originally have been their nameplate voltage?

I can see that raising the voltage considerably or reducing the load/current outside the nameplate values will cause the motor to speed up, and that this can result in excessive arcing or the commutator flying apart. But in a decent conversion the upper rpm should be limited by gearing or the controller, or by using a separate rpm limiter. Is it just that this motor looks particularly weak, or do you feel that many of us are pushing motors too far outside their safe working envelope? In my case I'm thinking of running a 36V/2500 rpm rated Prestolite motor at up to 120V, though I have advanced the timing several degrees to try to counter arcing.
__________________
Mini conversion:
http://www.diyelectriccar.com/forums...ad.php?t=52461
Reply With Quote
Reply

Share or Bookmark this

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 
Support DIY Electric Car
Sponsors

All times are GMT -6. The time now is 06:32 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Ad Management by RedTyger