# Curtis 1231C Behavior



## dimitri (May 16, 2008)

Hey Brian,

this weird thing never happened on my Miata with Curtis controller, but then again with Lead Acid batteries I wasn't flooring it too often. Just wanted to respond, so you don't feel ignored 

It sounds like back EMF from the motor suddenly disappears, which allows controller to push max amps again, weird 

At least your controller doesn't heat up like this pathetic Kelly I use for now


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## major (Apr 4, 2008)

bblocher said:


> However when the RPMs get high enough, maybe 3500 or something the amps suddenly jump up to 450-500 again and then again start to slow drop down as it continues to rev.


 
Hey bblocher,

I assume you're talking battery current here. What is the battery voltage while this is occurring?

I might be of more help if I knew your system voltage and motor curve. Got those?

And, it isn't a stupid thing like a slipping clutch? You'd probably have picked that one up.

Regards,

major


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## bblocher (Jul 30, 2008)

major said:


> Hey bblocher,
> 
> I assume you're talking battery current here. What is the battery voltage while this is occurring?
> 
> ...


Yeah, battery current is what I'm viewing. My voltage might get as low as 134v (144v nominal) at 500 amps but it's consistent with my amp draw. For example if I'm only at 350 amps my volts would be about 138-140. I'm using the ADC FB1-4001 motor.

Definately not the clutch, I'd see RPM spikes and probably under load compared to only happening after it's been reving steadily for a few seconds. Also this isn't jerking in both directions. I gradually see the amps starting to drop as it revs, then it's as if you hit the nitrous and the amps jump instantly from 350 to close to 500 again. At this point the amps start dropping back down again as it continues to rev. I expect the amps to drop as I rev it, but only once.


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## CrunchTime (Feb 13, 2009)

Would this be something to do with the current multiplication that Curtis talk about in the manual?



> During acceleration and during reduced speed operation, the Curtis PMC
> controller allows more current to flow into the motor than flows out of the
> battery. The controller acts like a dc transformer, taking in low current and high
> voltage (the full battery voltage) and putting out high current and low voltage.


It doesn't say specifically, but I assume that at some point it turns off the multiplication and takes high current and voltage from the battery and pushes it to the motor. I guess you'd need to compare the motor current to the battery current to see this happening...


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## major (Apr 4, 2008)

bblocher said:


> What I'm seeing is each time I shift gives and floor it the amps are maxed out (500ish). As the motor revs up the amps start to drop off and get down to about 350. From my understanding this is all normal with the series wound motors. However when the RPMs get high enough, maybe 3500 or something the amps suddenly jump up to 450-500 again and then again start to slow drop down as it continues to rev. By the time it gets to 4500-5000 rpms it's back down to the 350ish range.


Hi bblocher,

Looking at the FB1 curve for 144V, 500 amps is going to be at 3000 RPM. As you climb above 3000 RPM, current will decrease. At 3500 RPM, you should be down to 350 amps. And at 4500-5000 RPM, down to 185 to 220 amp range. These numbers will vary somewhat as that curve is calculated and at .03I droop. Your voltage numbers seem a little better. But, the numbers you state above don't make a lot of sense. How can you get 500 amps at 3500 RPM? and 350 amps at 4500?

Maybe your instruments are off? Or if correct, maybe the motor has a problem. But there again, it sounds like you feel the torque increase when the current increases. So that would indicate you're getting torque from those amps and the motor is o.k.

Well, just my thoughts, no obvious answer.

major


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## tomofreno (Mar 3, 2009)

Isn't 500A the 2 minute current for the 1231-4001 controller? Maybe the controller is shutting down current to protect itself, hot or not, then letting it climb again?

Tom


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## bblocher (Jul 30, 2008)

major said:


> Hi bblocher,
> 
> Looking at the FB1 curve for 144V, 500 amps is going to be at 3000 RPM. As you climb above 3000 RPM, current will decrease. At 3500 RPM, you should be down to 350 amps. And at 4500-5000 RPM, down to 185 to 220 amp range. These numbers will vary somewhat as that curve is calculated and at .03I droop. Your voltage numbers seem a little better. But, the numbers you state above don't make a lot of sense. How can you get 500 amps at 3500 RPM? and 350 amps at 4500?
> 
> ...


Yeah I'm not sure what's going on and if the amp gauge is corect.  It's used to also calculate my kW usage and that does seem to be working correctly.

I can hold 350 amps at 4500 RPM. I do this a lot climbing some of the hills going to work.

I dunno, it's working and working well so I can't complain. Just curious if anybody knew the inner logic on that controller.


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## bblocher (Jul 30, 2008)

tomofreno said:


> Isn't 500A the 2 minute current for the 1231-4001 controller? Maybe the controller is shutting down current to protect itself, hot or not, then letting it climb again?
> 
> Tom


I'm not sure on the 500 amp rating. I think 350 for 5 minutes and 250 for an hour is what I read somewhere.

Hard to say if this is a factor at all not knowing how they implemented this feature either. I'm not sure if it will slowly cut it back or if it's a on/off thing. Although from people I've heard talking about their controller going into limp mode it's a very noticable power drop and stays on for awhile. I can get this little power boost with just about every shift if I'm floored.


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## major (Apr 4, 2008)

bblocher said:


> I can hold 350 amps at 4500 RPM. I do this a lot climbing some of the hills going to work.


Are you sure the tach is calibrated? At 144V, 350 amps occurs at 3500 RPM. At 144V, 4500 RPM occurs at 215 amps. So, one of the 3 is incorrect, V, I, or RPM. Either that or you have a magic motor, or the ADC motor curve is wrong.

Regards,

major


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## bblocher (Jul 30, 2008)

major said:


> Are you sure the tach is calibrated? At 144V, 350 amps occurs at 3500 RPM. At 144V, 4500 RPM occurs at 215 amps. So, one of the 3 is incorrect, V, I, or RPM. Either that or you have a magic motor, or the ADC motor curve is wrong.
> 
> Regards,
> 
> major


The tach is correct. It's the stock tach and I remember RPM vs speed ratios from driving it when it was gas. Which graphs are you looking at? Maybe if I compare those numbers while driving I can figure out more. 

OH, the amps are on my battery side, sooo we really don't know what the motor is seeing. Can this be the missing part of the equation?


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## dimitri (May 16, 2008)

bblocher said:


> OH, the amps are on my battery side, sooo we really don't know what the motor is seeing. Can this be the missing part of the equation?


Motor can only see more amps than a battery, not less ( not counting heat losses in the controller )


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## major (Apr 4, 2008)

bblocher said:


> The tach is correct. It's the stock tach and I remember RPM vs speed ratios from driving it when it was gas. Which graphs are you looking at? Maybe if I compare those numbers while driving I can figure out more.
> 
> OH, the amps are on my battery side, sooo we really don't know what the motor is seeing. Can this be the missing part of the equation?


Hey bblocher,

http://www.evparts.com/img/mt2119torquecurvenofan.PDF 

The 144V curve is the top one. Amps are the same for all the RPM curves. Once you get up to 3000 RPM with it floored, you should come out of current limit (500A) and then the motor and battery current will be equal. Motor current is always greater than (or equal to) battery current. So, no way could you see 350 amps at 4500 RPM. You'd need like 185 volts to see that.

Memory can be a funny thing. I'd double check the tach. Sounds like you have an error in the pulse count ratio.

All this does not really explain the behavior you experience. Just that clearing this up would aid in pinpointing where the behavior is occurring. I happen to think that you are seeing a sag in the battery voltage at 500 amps. It is a temporary sag that recovers in a few seconds which then brings the current back up. Can you actually see a voltmeter while this occurs?

Regards,

major


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## dimitri (May 16, 2008)

My personal guess is that fancy LCD BMS that Brian has may not be as sharp as we expect. This is pure speculation on my part since I never owned one, but I follow Brian's project in great detail and he had some issues with this unit. Also, I don't know anyone else on this forum using same unit so we can't compare results.

At this point I would only trust a real analog ammeter connected to real matching shunt, not some fancy shmancy digital black box.

Unless, of course, Brian can actually feel additional torque with his butt in the seat when those amps jump..... can't beat the butt kick, its the best gauge ever  , but then again, it could be a matter of calibration and comparing apples to apples...


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## bblocher (Jul 30, 2008)

major said:


> Once you get up to 3000 RPM with it floored, you should come out of current limit (500A) and then the motor and battery current will be equal.


This is when I see the amps start to drop, but as I mentioned they magically jump up later. I will see if I can take a video of all of this. It's so hard to watch all the numbers at once while I'm driving. 



major said:


> All this does not really explain the behavior you experience. Just that clearing this up would aid in pinpointing where the behavior is occurring.


I agree, let me try to video this, hopefully get all the numbers on the screen at once so it can be replayed over and over. Then maybe we can make sense of it all.


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## bblocher (Jul 30, 2008)

major said:


> http://www.evparts.com/img/mt2119torquecurvenofan.PDF
> 
> The 144V curve is the top one. Amps are the same for all the RPM curves.


I'm having trouble seeing how you're correlating the RPM and AMP numbers. If I'm looking at this correctly the curve that decreases from left to right is the RPM vs Torque (for some unstated AMP rating?). The curve that increase from left to right is torque and hp vs AMPs?

Is this correct? Either way I still don't see how to tie the RMP and AMP numbers together in this graph.

Thanks!


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## major (Apr 4, 2008)

bblocher said:


> I'm having trouble seeing how you're correlating the RPM and AMP numbers. If I'm looking at this correctly the curve that decreases from left to right is the RPM vs Torque (for some unstated AMP rating?). The curve that increase from left to right is torque and hp vs AMPs?
> 
> Is this correct? Either way I still don't see how to tie the RMP and AMP numbers together in this graph.
> 
> Thanks!


Yeah, that has too many lines on it. So, erase all the HP curves. Erase the bottom RPM curves. Then you have left one RPM curve at 144 V and the Amps curve. Got that?

Now, find 4500 RPM. That would be at 39 lb.ft. Right? At 39 lb.ft., read the Amp curve. 220 Amps. Right?

So, if you have 4500 RPM and 144 volts, the motor current will be 220 amps. End of story. No other possible value. So, like I said, the V, I and RPM values you state do not correlate.

Now, if you extend the Amp and RPM curve a few inches, you can see that 500 amps will occur at about 120 lb.ft. and the RPM will be about 3000. That is where you should come out of current limit and the motor voltage equal battery voltage and motor current equal battery current, if you have it floored.

Just remember these motor curves are drawn with the load (torque) as the independent variable. So for a stated motor voltage (144), at a given load (torque), the RPM curve tells you the speed and the Amps curve tells you the motor current. Or if you know the current, find the torque for those amps on the amp curve and then read the RPM for that torque. Or vice versa.

Hope that wasn't too confusing,

major


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## bblocher (Jul 30, 2008)

major said:


> Yeah, that has too many lines on it. So, erase all the HP curves. Erase the bottom RPM curves. Then you have left one RPM curve at 144 V and the Amps curve. Got that?
> 
> Now, find 4500 RPM. That would be at 39 lb.ft. Right? At 39 lb.ft., read the Amp curve. 220 Amps. Right?
> 
> ...


If I take the line labeled as "Calc 144 Volt, RPM" at 4500 RPM I see the 39lb ft. If I drop down to the line labeled "H.P. 144 Volt" that appears to be more like 340 amps (which is what I'm seeing the motor do). Are you dropping down to the other dashed line for 96v (this one appears to be about 220)?

They could at least do a color chart


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## major (Apr 4, 2008)

bblocher said:


> If I take the line labeled as "Calc 144 Volt, RPM" at 4500 RPM I see the 39lb ft. If I drop down to the line labeled "H.P. 144 Volt" that appears to be more like 340 amps (which is what I'm seeing the motor do). Are you dropping down to the other dashed line for 96v (this one appears to be about 220)?
> 
> They could at least do a color chart


Erase all the HP curves. Forgetaboutthem. Just look at the solid line for the Amps curve. See the word "Amps" and an arrow pointing to a solid curve? It runs from about 10 lb.ft., 100 A to 100 lb.ft., 425A.

Didn't have colors back in 1991 when that was drawn

major


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## bblocher (Jul 30, 2008)

major said:


> Erase all the HP curves. Forgetaboutthem. Just look at the solid line for the Amps curve. See the word "Amps" and an arrow pointing to a solid curve? It runs from about 10 lb.ft., 100 A to 100 lb.ft., 425A.
> 
> Didn't have colors back in 1991 when that was drawn
> 
> major


I didn't see that line hidden in there.  I see how you're getting the numbers now.

We'll crap, that number is no where close to what I'm seeing on my amp guage. I'll do a quick numbers check on the tach. I do remember the numbers very well because I knew have fast I could go before hitting the 9k rev limiter. For example 62 mph was 9k. So in 2nd I should see about 30 mph around 4500 RPM. If that matches I can at least rule that out.

Thanks for the help, I'll post more info as I collect it.


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## bblocher (Jul 30, 2008)

I tested the tach out this morning and it was as I thought. 2nd gear, 4400-4500 RPM and I was at 31 MPH.

So either the AMP gauge is wrong, or the graph is wrong.


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## dimitri (May 16, 2008)

bblocher said:


> I tested the tach out this morning and it was as I thought. 2nd gear, 4400-4500 RPM and I was at 31 MPH.
> 
> So either the AMP gauge is wrong, or the graph is wrong.


I suspect your amp gauge, your amp reports overall seem on a high side. I realize that you got hills and all that, but still, 500Amp on a battery side of 500Amp controller seems too optimistic even for Curtis, that means 100% duty cycle, which should not last more than 1-2 seconds.


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## bblocher (Jul 30, 2008)

dimitri said:


> I suspect your amp gauge, your amp reports overall seem on a high side. I realize that you got hills and all that, but still, 500Amp on a battery side of 500Amp controller seems too optimistic even for Curtis, that means 100% duty cycle, which should not last more than 1-2 seconds.


I think the next step will be to add a temporary analog amp gauge also on the battery side and compare numbers.


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## major (Apr 4, 2008)

bblocher said:


> I think the next step will be to add a temporary analog amp gauge also on the battery side and compare numbers.


Hey Brian,

Any news?

major


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## bblocher (Jul 30, 2008)

major said:


> Hey Brian,
> 
> Any news?
> 
> major


I haven't had time yet sadly.


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## bblocher (Jul 30, 2008)

Anybody know where I can buy a cheap 500 amp ammeter for this testing? I have a 50mv shunt already laying around.


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## TheSGC (Nov 15, 2007)

bblocher said:


> Anybody know where I can buy a cheap 500 amp ammeter for this testing? I have a 50mv shunt already laying around.


Just attach a DVM (Digital Volt Meter) and set it to mV and that should work fine. 50mv = 500 AMPs, so 0.1mv is 10 AMPs, etc. That is what I have been using since it's cheap and allows for debugging before I install the final setup.


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## major (Apr 4, 2008)

bblocher said:


> Anybody know where I can buy a cheap 500 amp ammeter for this testing? I have a 50mv shunt already laying around.


Brian,

The meter is actually a 50 mV full scale meter movement. It is just the scale which reads 500 amps. So any 50 mV, or higher, meter will work. You just have to do a conversion if it is scaled differently. Or, even use a multimeter on the millivolt scale. One millivolt equals 10 amps, if the shunt is 50 mV, 500A.

Regards,

major


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## bblocher (Jul 30, 2008)

Thanks guys. I thought about the multimeter but wasn't sure how accurate that would be. Hopefully I have a couple of spare lugs and a short piece of 2/0 laying around too then so I can try this tonight or tomorrow.


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## bblocher (Jul 30, 2008)

Ok I did the testing this morning with the multimeter. It matched my other amp readings very closely. So it's not off either and again I'm positive the RPM gauge is correct. Maybe that motor graph is wrong?

I did another test this morning that really showed the condition I'm seeing too (which again, isn't bad). So I shifted into 6th gear (which I never use) at about 50mph which dropped by RPMs down to below 3k or so. I floored it and it acclerated slowly. Basically it gave me a good 5-10 seconds of watching the amps slowly dropping. I got down to about 350 amps or less just before 4k RPM. As soon as I hit 4k RPM it jumped up to 450 amps. You could feel the sudden acceleration increase. So it's not like a quick little increase after flooring it. It was quite some time after flooring that it did it, and it seems to be tied to the motor RPM reaching this magic 4k range.


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## major (Apr 4, 2008)

bblocher said:


> Ok I did the testing this morning with the multimeter. It matched my other amp readings very closely. So it's not off either and again I'm positive the RPM gauge is correct. Maybe that motor graph is wrong?


Hi Brian,

I seriously doubt the motor graph is that far off. It has been around since 1991. And if they changed motor design, they would have given it a new number. Unless you have a lot higher voltage than I think, at 4000 RPM the motor current is 275 amps.

So, I'd like to know what the actual motor voltage is when this magic occurs. Can you put a voltmeter right on the motor terminals?

Regards,

major

ps. Looking again at the motor curves. The curve I have been using is for FB1-4001, curve #XC-59 dated 3-15-91 and has RPM curves for 75, 96, 120 and 144 volts. I have another curve for FB1-4001, curve #C-59, dated "Redrawn & Revised 9-17-91". It has RPM curves for 75, 96, and 120 volts. There is a difference between these curves.

You're interested in the 4000 RPM point with 144 volts. The later curve does not have the 144V RPM curve. So, let's use 2000 RPM on the 72 volt curve. It says 75, but basically, you're running twice voltage, so we can look at half speed on a half voltage curve. Got that?

So, 2000 RPM on the old curve (XC-59) gives us 51 lb.ft. and 260 amps. 2000 RPM on the later (C-59) gives us 66 lb.ft. and 350 amps. That is a pretty big difference. I guess the guy that drew those curves was an idiot. 

At any rate, this may explain some of the higher current you read. Please run the motor voltage test.


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## bblocher (Jul 30, 2008)

Luckily I was working from home today so was able to do this immediately. I'm really shocked at the result too. I was expecting to see changes in the motor voltage because of the Curtis "whine" feature. I thought it dropped my voltage significantly during this stage. As soon as my contactors were closed I saw full pack voltage all the time. Under high amp draws the voltage was slightly less on the motor side (controller inefficiencies of course).

So I repeated the test of shifting into a gear that would put me at about 3k RPM and floor it. As the RPMs went up the amps would start drop and the pack and motor voltage would increase. Just before the 4k RPM mark the motor voltage was about 134v, when the "boost mode" kicked in the motor voltage dropped down to 131v or so. This normal of course since my amps are jumping up. I saw the biggest jump today I think (480A for a split second) but the display updated and it was 450 and dropping as it continued to accelerate. I think it's down to like 325+ amps at 5k RPM. I've can't remember if I mentioned this, but I did some tests on the hills going to work and I can hold 450 amps for long periods of time as well over 4k while I'm accelerating up hill. So it's not like the controller is just giving a quick blimp of current and then being reduced.

I honestly can't imagine the power, or lack there of, if my motor was limiting my controller to 250 amps at 4k (if those were the correct numbers stated). It would be very under powered and I'd be fighting to climb the grades going to work.

Not sure this info helps any though. I also talked to a guy who works for Curtis and he said the controller has no feature or logic that would kick in, or be cutting back for that matter, any current consistently like that.

So what is the physics behind the current limitations? I'm guessing there is a building resistance that only allows so much current for a given voltage but I don't fully understand this.


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## tomofreno (Mar 3, 2009)

Major,

I've found discrepancies between other ADC graphs, though not that large. I have an undated graph from ADC entitled "Typical FB1 Type 9" Motor Performance, 144 Volt - 0.03I CCW Drive End Rotation". It is marked C-59, Sheet 3 on the side. At 70 lb-ft torque it gives about 4000 rpm, 350A.

Tom


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## major (Apr 4, 2008)

bblocher said:


> As soon as my contactors were closed I saw full pack voltage all the time. Under high amp draws the voltage was slightly less on the motor side (controller inefficiencies of course).


Hi Brian,

Almost instant feedback. I like that.

But this statement "As soon as my contactors were closed I saw full pack voltage all the time" bothers me. Seems like your meter is reading the peaks on the PWM to the motor. Not what we want to see. Any chance you can put an old fashion analog meter on it?



> So what is the physics behind the current limitations?


That would be Ohm's Law

Regards,

major


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## honn1002 (Nov 26, 2008)

Brian, 

If you look at the specs of 1231C, the controller puts out “constant current limit over operating range, and linear rollback over-temperature.” The controller’s ambient operating temperature range is -25C to 50C degrees. When you have a good cooling for the controller to be within the ambient operating temperature, the controller still puts out up to the current limit as long as the temperature does not exceed 50C. If the temperature passes 50C the current limit will go down to protect itself from over-heat damage. 1231C doesn’t have any digital timing to control the current limit, it's an analog series controller. It’s all depending on the operating temperature of the controller. The current limit spec is for when you use the controller without any additional good cooling system. In your case I think you have a very good cooling system.


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## bblocher (Jul 30, 2008)

major said:


> Hi Brian,
> 
> Almost instant feedback. I like that.
> 
> ...


I'd have to buy one, nothing laying around 
I understand Ohm's law, I just don't understand why the resistance in the motor is increasing as the RPMs increase.


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## bblocher (Jul 30, 2008)

honn1002 said:


> Brian,
> 
> If you look at the specs of 1231C, the controller puts out “constant current limit over operating range, and linear rollback over-temperature.” The controller’s ambient operating temperature range is -25C to 50C degrees. When you have a good cooling for the controller to be within the ambient operating temperature, the controller still puts out up to the current limit as long as the temperature does not exceed 50C. If the temperature passes 50C the current limit will go down to protect itself from over-heat damage. 1231C doesn’t have any digital timing to control the current limit, it's an analog series controller. It’s all depending on the operating temperature of the controller. The current limit spec is for when you use the controller without any additional good cooling system. In your case I think you have a very good cooling system.


This makes perfect since, and I'm not saying it's the controller causing it. I probably should have just put this post in the tech section since I really don't know what I'm experiencing. I think the controller is working fine. 

It's as if the resistance in the motor drops at 4k RPM and the controller can push more through.


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## honn1002 (Nov 26, 2008)

bblocher said:


> This makes perfect since, and I'm not saying it's the controller causing it. I probably should have just put this post in the tech section since I really don't know what I'm experiencing. I think the controller is working fine.
> 
> It's as if the resistance in the motor drops at 4k RPM and the controller can push more through.


Brian,

I’m thinking the same thing as you’re thinking. It got to be the resistance and inductance in the motor at 4K RPM and the controller can push more through. We know that the controller’s output current is depending on the load of the motor. Less load less current output from the controller, more load more current output from the controller up to the maximum current limit the controller is able to put out. If the controller is over-temperature, the current limit is cutting back so regardless how much load you have the controller only puts out whatever the current limit is available at that operating temperature.


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## major (Apr 4, 2008)

bblocher said:


> I just don't understand why the resistance in the motor is increasing as the RPMs increase.


It's not. Something else is going on. Motor resistance changes slightly as temperature changes, but this is not what you're seeing. But motor resistance does not change otherwise. If you see a change in motor current at a given RPM, then there has to be a change in motor voltage. That's what I'm looking for.

A field weakening circuit might explain the jump in current at a given RPM, like your 4000. But you do not have such a circuit. An internal coil short in the motor could cause unintended field weakening, but would not be repeatable as you describe. And, at 400-500 amps, internal motor shorts would be letting out some smoke.

I say the behavior is a result of the controller. Need to see good data on the motor voltage.

Regards,

major


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## zeeman1953 (Apr 5, 2009)

Hi, I'm new to all this but when a read about the Curtis 1231C controller problems I have to ask about my Curtis 1221C controller. I have been slowly converting a 95 Metro with a Curtis controller and a Warp 9 Impulse motor. The Curtis manual shows the a heavy wire coming off the motor "A2" and going to the "A2" of the controller. In scanning the available schematics online, I don't see this terminal being used ...except for reversing purposes. The manual schematic shows a simple diagram (w/o reversing) which will mostly serve my needs. My question is...do I need this additional wire? Thanks
________
RC161


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## major (Apr 4, 2008)

zeeman1953 said:


> I don't see this terminal being used ...except for reversing purposes. The manual schematic shows a simple diagram (w/o reversing) which will mostly serve my needs. My question is...do I need this additional wire? Thanks


Hi zee,

No, you don't need the A2 connection for non-reversing applications. However, Curtis does show it wired to A2 on the motor for non-reversing applications in their manual. So, I'd do it. It is a plug diode connection inside the controller. Without reversing contactors, you can't plug. Connecting it anyway won't hurt, and if you ever have a warranty claim, Curtis can't complain about it not being there.

Regards,

major


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## bblocher (Jul 30, 2008)

zeeman1953 said:


> Hi, I'm new to all this but when a read about the Curtis 1231C controller problems I have to ask about my Curtis 1221C controller. I have been slowly converting a 95 Metro with a Curtis controller and a Warp 9 Impulse motor. The Curtis manual shows the a heavy wire coming off the motor "A2" and going to the "A2" of the controller. In scanning the available schematics online, I don't see this terminal being used ...except for reversing purposes. The manual schematic shows a simple diagram (w/o reversing) which will mostly serve my needs. My question is...do I need this additional wire? Thanks


I'm not an expert on this so please correct me if I'm wrong. The ADC FB1-4001 and the Warp 9" are series wound and using an advanced timing. It doesn't matter which way you hook up your power, the motor will only spin one way. The A2 connector on the controller is probably for motors that a seperately excited field coil? I'm not sure on all the motor styles and how they work but positive you don't need it for your Warp 9.


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