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You control the torque with amps and voltage. The voltage won't give you torque but amps will. It then depends upon what your controller can belt out. That is why I say you want a controller that will belt out better than 500 amps when you need it or want it. Not that you have to do that all the time mind you. So a Soliton can belt out more amps into the motor than my synkromotive which can belt out more than the typical Curtis. The Zilla 2K beats them all. Or you could just go with a contact switch and have full amps available like right now but no control of the amps. Then it depends upon if your batteries can provide the level of amperage you desire. My 1C 100 AH cells cant belt out more than what my synkro can tolerate. I'd bet the new TS cells could over power my Synkromotive if I did not limit my current.

So you see there are many variables. Can't answer your question.

Pete :)
 

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ok, lets add the restriction of '144v at 500 battery amps'.
The voltage is irrelevant to torque, it will apply to the rpms where full torque is available, but torque is a matter of amps with a series wound motor.

The ADC 9 inch motor and WarP 9 motor (not Impulse 9 motor) that are commonly used will make about 100 ft-lb of torque at 500 amps. With a 144 volt pack that sags to about 126 volts at 500 amps you can expect to make peak torque from 0 rpm to about 3700 rpm. You will have about 71 HP at about 3700 rpm.
 

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With a 144 volt pack that sags to about 126 volts at 500 amps you can expect to make peak torque from 0 rpm to about 3700 rpm.
Really? Looks more like 2700 - 2800 rpm to me from the torque-speed curves, but I have no real experience with it. Edit: Whoops, sorry, I was reading the graph incorrectly, looks like around 3400 rpm on the graph so 3700 seems reasonable.
 

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...trying to make sure tranny can handle it....
Your tranny can maybe take 100 lbs-ft at the input..... but if you have small tire, they can't transmit all this torque to the ground! (especially in first, second and third gear). So, the wheels spin and the input torque at the transmission is lower than 100 lbs-ft.
 

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Discussion Starter #8
excellent info, exactly what I need to ask the next question. ;)

If I can expect torque of about 110 ft# from 500 amps... but want more and go out and get a controller capable of delivering say 1000amps the question becomes 'how long can I put 1000 amps into a 9" DC motor before I have thermal problems', and would the 1000 amp controller deliver 220 ft#.

the followup question would be along the lines of which would have thermal problems first, the motor or Thundersky/CALB cells that were being asked to deliver 10C ?
 

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...trying to make sure tranny can handle it... what is the max torque delivered by 9" DC motor w/ 144v pack? can't find a graph to answer from ADC or Netgain, or maybe I am reading them wrong.
You might look at some calculations I did a while back, particularly the curves at the bottom: http://www.diyelectriccar.com/forums/showthread.php?t=39931&highlight=motor+theory
I think the first thing to go is the Commutator at about 100kW, but your battery pack wont quite deliver that.
Gerhard
P.S. Note that there is still an unresolved discrepancy between Netgain's published curves and data from forum members.
 

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excellent info, exactly what I need to ask the next question. ;)

If I can expect torque of about 110 ft# from 500 amps... but want more and go out and get a controller capable of delivering say 1000amps the question becomes 'how long can I put 1000 amps into a 9" DC motor before I have thermal problems', and would the 1000 amp controller deliver 220 ft#.

the followup question would be along the lines of which would have thermal problems first, the motor or Thundersky/CALB cells that were being asked to deliver 10C ?
I have that motor and a Curtis 1231C which I'm having upgraded to 1000A. I can get you the guy's info if you're interested. It's a $650 upgrade which will also make it run cooler for a given voltage. Since I upped my voltage I'm having heat problems even in cooler night time temps. I'm also adding a heatsink but reducing the source of heat will help as well. He said likely I wouldn't need fans after the upgrade as long as I had the heatsink installed. Now that would really be an improvement!

I am working to get my truck to be as functional as the gas version. Now at highway speeds it overheats if trying to maintain 65-70mph. The guy told me it's the diodes inside which create a lot of heat at 160-165V.
 

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Hey EC, regarding the upgrade, will your controller be able to recognize the additional 500A or does the upgrade also changes the current measurement so it reads half of actual? Would it be possible to find out the part number of the new switches they're swapping in? I curious to look in the spec sheet.

JR
 

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the followup question would be along the lines of which would have thermal problems first, the motor or Thundersky/CALB cells that were being asked to deliver 10C ?
I think you should go with Headway cells or similar (cylindrical cells with thinner electrode coatings for higher power) rather than subjecting TS or CALB to 10C.
 

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I actually got the impression from Tess that Sol-1's could do 500/600 amps continuous with just the air cooling depending on ambient..
 

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I actually got the impression from Tess that Sol-1's could do 500/600 amps continuous with just the air cooling depending on ambient...
I think so, depending of course on what ambient is. I expected that he may have in mind higher continuous current than that (though I hope not on public streets :eek:), and also not sure if the above is possible in something like 100F ambient.
 

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so, the continuous rating is not changed... just the max burst. I'd consider something like Soliton Jr, or Soliton 1 if you really need something designed for higher continuous power....
The 1 hour rating for the Curtis is 225A stock. Here's data from Cloud Electric site on the controller.

Peak Current Rating: 500A
2 Min Current Rating: 500A
5 Min Current Rating: 375A
1 Hour Current Rating: 225A

So the upgrade results in the 2 minute rating being doubled and the 1 hour rating is boosted 78%, nearly doubled.
 
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