# Who's running a larger sepex out there???



## DIYguy (Sep 18, 2008)

Been looking and haven't seen/found much on Sepex applications. Even though I have a 9 GE series in my project truck... I can get my hands on some monster Sepex motors...anything from a sweet looking 11" GE up to several monster 40 hp and even a couple of 50 hp motors. These things are massive...suitable for a bus I would say...lol 

I would pick up the 11" 20 odd hp GE (says Reliance..but I think it is a GE) motor if it was thought worth while. I understand they can do regen easy enough...but what about the controller. Don't you have to vary the field current as well as PWM the to the armature? 
I would only be interested if I could get some good performance out of it with a fairly high voltage pack.

What do you know Major?


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## Guest (Jul 22, 2009)

Kelly has them. I have one for 72 volts. It is a SepEx 72 volt 600 amp controller and it does vary the field current when needed and does regen and field weakening. I do not have a 72 volt SepEx motor to test this but it when ready it will be converted to power the old military style starter/generators at 72 volts and 600 amps. I am sure it would do fine with a GE motor of 9" or less SepEx. Got some photos of those monster SepEx motors? I'd love to test some Kelly's out on those. Got any 9" SepEx motors? 

Pete


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## Guest (Jul 22, 2009)

Kelly will work with you on larger controllers for your needs. 


Pete


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## major (Apr 4, 2008)

DIYguy said:


> Don't you have to vary the field current as well as PWM the to the armature?


Hi guy,

Yes, you should control both the armature and field. I am not aware of any available controllers for high power high voltage SepEx motors. You need to have the controller tuned to the particular motor, which I see as a problem unless you can get detailed design information on the motor and be able to program the controller.

Regards,

major


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## DIYguy (Sep 18, 2008)

gottdi said:


> Got some photos of those monster SepEx motors? I'd love to test some Kelly's out on those. Got any 9" SepEx motors?
> 
> Pete


Hey Pete,

Check out these pics. No 9" sepex... smallest is 11". Biggest is 18" dia by about 42" long. I haven't checked to see if they are all (there are more than these pics) Sepex... but probably as they needed precise speed control for feeding steel coils into blankers. Fist pic is a 20 hp with a heavy brake on it, next two are 40 hp last pic is of two that are over 50 hp I think.

Gary


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## toddshotrods (Feb 10, 2009)

Those are pretty big motors! Probably pretty heavy too. I have an 11-inch SepEx GE going in my race rod project. Mine is roughly the same size as a NetGains WarP 11.









As for controllers, getting one matched up to the motor is the challenge. Eventually, I plan to dig in and start figuring out the field map since I can't find it anywhere. Before you buy one of those motors do some research to see if you can find the factory field map, or be prepared for a lot of work and testing to develop one.


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## DIYguy (Sep 18, 2008)

toddshotrods said:


> Those are pretty big motors! Probably pretty heavy too. I have an 11-inch SepEx GE going in my race rod project. Mine is roughly the same size as a NetGains WarP 11..


That' just a baby motor compared....... lol


toddshotrods said:


> As for controllers, getting one matched up to the motor is the challenge. Eventually, I plan to dig in and start figuring out the field map since I can't find it anywhere. Before you buy one of those motors do some research to see if you can find the factory field map, or be prepared for a lot of work and testing to develop one.


When u say "map" do you refer to schematics? I have all the data on voltage and current for feild and armature for the one I would be interested in...which is probably the same or similar as yours. I will list the details tomorrow....


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## toddshotrods (Feb 10, 2009)

DIYguy said:


> That' just a baby motor compared....... lol


Yup 




DIYguy said:


> ...When u say "map" do you refer to schematics? I have all the data on voltage and current for feild and armature for the one I would be interested in...which is probably the same or similar as yours. I will list the details tomorrow....


Here's the basic process Tesseract gave me for determining the field map:


> Some of the field map can be derived through measurement with the data you copied off of the nameplate; specifically, the rated output power at a given RPM. Your motor says it can deliver 14kW at 1000 rpm (at 48V/330A, implying a very respectable efficiency of 88%).
> 
> The basic procedure is to then hook the motor up to a dyno and feed the field and armature separately until the shaft is spinning at 1000 rpm while the armature is drawing 48V/330A. I would expect the field current to be somewhere in the range of 30-100A at that point. You can use two separate series motor controllers to do this testing, btw, but make absolutely sure there is always a load on the motor shaft and some minimum level of field current present (say, 5A). A sepex motor will overspeed and/or fireball if field current is lost or too low while armature current is flowing.
> 
> ...


I am still searching hoping to find the GE factory filed map before going through all that though. Please share any info you get.


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## major (Apr 4, 2008)

toddshotrods said:


> Here's the basic process Tesseract gave me for determining the field map:
> 
> 
> > Some of the field map can be derived through measurement with the data you copied off of the nameplate; specifically, the rated output power at a given RPM. Your motor says it can deliver 14kW at 1000 rpm (at 48V/330A, implying a very respectable efficiency of 88%).
> ...


Or just test the no load saturation curve. But either way, you still have to have a controller to program it into.



> I am still searching hoping to find the GE factory filed map before going through all that though. Please share any info you get.


Unless your uncle works for GE in that department, you're looking at a dead end 

Regards,

major


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## toddshotrods (Feb 10, 2009)

major said:


> Or just test the no load saturation curve...


How do you do that?



major said:


> ...
> Unless your uncle works for GE in that department, you're looking at a dead end ...


I've noticed.  I just poke around every once in a while, when the issue is on my mind, hoping to stumble across somebody who has or has access to the information.

Actually, this reminds me that I forgot to follow up on one lead. There was a company selling used/rebult motors on Ebay that claims to be able to program an Alltrax to work with my exact motor (GE 8504666) - I hope I still have the phone number.

*EDIT*
Found the number and called - their Ebay ad was a lie. The guy didn't even understand what I was talking about. I had to try and explain in my layman's terms what it was, and he admitted that they don't have the info. He confirmed the near impossibility of getting any help from GE. He said they won't even give them that kind of info and they're a distributor.


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## major (Apr 4, 2008)

toddshotrods said:


> How do you do that?


Hi todd,

Drive the motor at a constant RPM with another motor, like a small induction motor. It won't take much power, like a 1/5 hp would do. Maybe belt drive so the big motor is turning at like 1000 RPM. Doesn't really matter. Could be 872 RPM or 1138 RPM, just has to be constant RPM through the test. It is at no load, so a set RPM should stay constant.

Put a voltmeter on the big motor armature terminals, usually A1 and A2.

Hook the field up to a variable voltage supply. Hopefully it will have a current meter. If not, wire in an ammeter. While the motor is running at the constant RPM, read the armature voltage. With zero field voltage, zero field current, the armature voltage should read zero or close to it. Record that voltage. Crank up the field voltage so the field current is one amp. Read and record the armature voltage. Go to 2 amps on the field. Read and record the armature voltage. Then 3 amps on the field. So on and so on. As high as your field power supply will go. For a big motor like this, you may need 50 amps or more. 

Then plot your data, armature volts vs field amps. Vola, you have the no load sat curve. Actually the no load magnetization curve to be technically correct. But that is what you really want.

Do that and post it up and I'll explain how to figure a field map from it. 

Regards,

major


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## Tesseract (Sep 27, 2008)

major said:


> ...Drive the motor at a constant RPM with another motor...


This is a much better method than the one I thought of... Todd, it probably goes without saying, but when it comes to motors, if what major says conflicts with what I say, you'd best defer to major


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## toddshotrods (Feb 10, 2009)

major said:


> ...Drive the motor at a constant RPM with another motor...
> Do that and post it up and I'll explain how to figure a field map from it. ...


Wow, this is awesome major! I can't do it right away (have more than a plate full at the moment), but I will definitely jump on this at the first opportunity. Between making progress with my chassis and this, I'm getting some pep back in my step! 



Tesseract said:


> This is a much better method than the one I thought of... Todd, it probably goes without saying, but when it comes to motors, if what major says conflicts with what I say, you'd best defer to major


Copy that, but you're still "the man"!


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## major (Apr 4, 2008)

Tesseract said:


> This is a much better method than the one I thought of... Todd, it probably goes without saying, but when it comes to motors, if what major says conflicts with what I say, you'd best defer to major


Yeah, Tesseract,

I got a few years of experience on ya, I think. 

I had to do this very thing a few years ago. It was a 6.6" GE motor without a drive bearing. So I couldn't drive it with another motor on the bench. Ended up putting one drive wheel of the vehicle on a treadmill to back drive the motor at a constant RPM. Worked great.

Live and learn,

major


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## DIYguy (Sep 18, 2008)

Thanks guys.... here are specs on the 11 motor. Is this enough info to constitute a "map" allowing the matching to a controller perhaps? 

The motor is labeled as a Unico motor, made in Franksville Wisconson.

Type: GE-40-2000 S/N: 182795
P/N: 106-249 Wound Field DC Motor
Frame; 2110AT Dwg: 106-249
P (hp): 20 S (rpm): 2491

Armature:
Lead Marking: A1-A2 for CW from shaft end.
E(vdc): 240 IA(adc): 74.4
Amb *F: 104 Rise *F: 170 Duty(hr): 24
KT(lb-ft/amp):0.622 KV(volt/rpm): 0.688
JA (lb-ft sec2): 0.041 RA(ohm) 0.256 LA(hry): 0.0035

Field:
Type: Shunt
This part of the label shows how to connect Series or Parallel and has the following values for each........

Series; 
EF(vdc): 300 IF(adc):1.17 RF(ohm):183 LF(hry):104

Parallel;
EF(vdc): 150 IF(adc): 2.34 RF(ohm):46 LF(hry): 26


Regards,
Gary


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## DIYguy (Sep 18, 2008)

What do you gents think of using one of the original industrial Unico drives that were made to run this motor? At least the characteristics for the field and armature would be correct. These were analog DC motor variable speed controllers made to run from 3 phase input, like 480VAC.... but perhaps this part could be changed to DC....????


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## major (Apr 4, 2008)

DIYguy said:


> Thanks guys.... here are specs on the 11 motor. Is this enough info to constitute a "map" allowing the matching to a controller perhaps?


Hi Gary,

From the nameplate data you show, this looks like what I would call an industrial shunt wound motor. It is not your typical SepEx motor intended for EV propulsion. I think it will be difficult, to say the least, to use this motor and get acceptable performance in an EV application.

As far as a field map, the data provides the required "full" field excitation values. This is a good starting point. But even when wired in parallel (for 150V), the field resistance is too high to be able to properly overexcite it for overloads, like when accelerating. You can figure the low load end of the map where you'd be field weakening. 

It might be possible to use this motor in an EV, but it will require a lot of work on the control. Or rewind the field coils. Probably more that it is worth, in my opinion.

Regards,

major


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## DIYguy (Sep 18, 2008)

major said:


> Hi Gary,
> 
> From the nameplate data you show, this looks like what I would call an industrial shunt wound motor. It is not your typical SepEx motor intended for EV propulsion. I think it will be difficult, to say the least, to use this motor and get acceptable performance in an EV application.
> 
> ...


Thank you Major. Once again, your knowledge has helped me (and likely others). In this case, I won't waste my time. When I saw those motors sitting there... I was just drooling a little bit... lol My build is already together with a 9" GE series motor which should perform just fine I hope.

Can you describe briefly, the difference between a SepEx and shunt wound motor (I know I should look it up). It may be an appropriate place for an explanation for those who may follow this thread in the future. (not to mention me ) 
take it, a shunt wound motor still has a field that is separately excited....? 

Cheers,
Gary
Edit.......when you suggest rewinding the field coils.... I assume you meant to a series configuration? Could this be achieved?


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## major (Apr 4, 2008)

DIYguy said:


> Can you describe briefly, the difference between a SepEx and shunt wound motor (I know I should look it up). It may be an appropriate place for an explanation for those who may follow this thread in the future. (not to mention me )
> take it, a shunt wound motor still has a field that is separately excited....?


Hi Gary,

I've seen a lot of guys take a lot of crap about the differences between shunt and SepEx. But what the H. Here goes.

The classical definition of a shunt motor is where the field voltage equals the armature voltage. In other words, the field shunts the armature.

The classical definition of a separately excited motor is where the armature and field are powered from different sources and can be independently controlled. ie. The field voltage is not necessarily equal to the armature voltage. And the field current isn't necessarily the same as the armature current (that would be a series motor).

Now a motor designed as a shunt wound motor can be field weakened, as by putting a resistor in series with the field to lower the field current. If this is done, is it still a shunt motor? That would be how the motor factory labeled it. But the field voltage is no longer equal to the armature voltage so it does not fit the classical definition.

While I'm on it, the similar situation exists for the series motor. It can be field weakened by placing a resistor across the field. Then the field current is not equal to the armature current and it no longer fits the classical definition. Is it still a series wound motor? The factory would have labeled it that way.

So, here is my simple take on the difference between a shunt wound and a SepEx motor.

A shunt motor is designed to run at a fixed field voltage, most times equal or near the rated armature voltage. It can be field weakened, but is not readily overexcited in the field.

A separately excited (SepEx) is designed to have the field voltage significantly below the rated armature voltage so it can be overexcited as well as weakened.

Here is just an example (so don't go wind a motor this way )

A shunt motor might have a field designed for 300V, 1.17A with a resistance of 256 Ohms(*), having 1000 turns per coil (T/C).

And equivalent SepEx motor would have a field designed for 30V, 11.7A with a resistance of 2.56 Ohms and 100 T/C. The wire size would have 10 times the cross section as in the shunt motor coil.

At rated field strength, both motors would have 1170 ampere turns (AT) per pole. Both motors would run exactly the same, same torque, same RPM, same efficiency.

Both motors can be field weakened by reducing the field voltage and therefore the field current and the AT. But, it is difficult to increase the field voltage on the shunt motor because of the high initial voltage, whereas it is easier to increase the field voltage on the SepEx motor because of the lower than usual initial field voltage. 

This means that SepEx motors can be more easily overexcited which is important in overload applications such as large mass acceleration. When at overload, the SepEx controller will overexcite the field such that the SepEx motor mimics the characteristics of a series wound motor. Hence the need for a field map in the control program. By mimicking the series motor, the SepEx can overcome some difficulties common to shunt motors in overload applications, namely good torque per amp and acceptable commutation.



> Edit.......when you suggest rewinding the field coils.... I assume you meant to a series configuration? Could this be achieved?


No, what I was talking about was similar to my example above, making it a usable SepEx. But as long as you were rewinding it, you could do a series wind. Not saying either is practical for your situation, but is certainly possible.

Regards,

major


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## DIYguy (Sep 18, 2008)

Thanks Major. An excellent description for a guy like me. It makes perfect sense. I think a lot of ppl will benefit from that write up. 

Admin; Perhaps that should go in the Wiki??


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## steiner (Dec 8, 2008)

Major,

I have an 11" GE motor identical to the one that toddshotrods has. I read your post pertaining to mapping the motor. I performed the test that you described except my power supply only would go up to 15 amps. Here is the data that I recorded.

Speed - 1318 RPM
Voltage across A1 and A2 with no field current - .465 volts
Resistance across A1 and A2 - .1 ohms (approx)
Resistance across F1 and F2 - .3 ohms (approx)

Current thru F1 and F2, voltage readings across A1 and A2
1A - 2.32 volts
2A - 3.53 volts
3A - 4.93 volts
4A - 6.29 volts
5A - 7.62 volts
6A - 9.27 volts
7A - 10.78 volts
8A - 12.23 volts
9A - 13.90 volts
10A - 15.40 volts
11A - 16.67 volts
12A - 18.09 volts
13A - 19.48 volts
14A - 20.88 volts
15A - 22.31 volts

I certainly appreciate any help you can provide.

Rick


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## major (Apr 4, 2008)

steiner said:


> Major,
> I certainly appreciate any help you can provide.
> Rick


Hi Rick,

I'm on the road for a few days. Get back to you later. 

Anyone else care to jump in?

Regards,

major


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## steiner (Dec 8, 2008)

Major,

Thanks.....quick question....Is this enough data or will I need to record the data at higher values of current at F1-F2? Are we just trying to get the slope of the data or something more specific?

Rick


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## Georgia Tech (Dec 5, 2008)

Form the photos these motors look like something from HUGE industrial Machinery, like Really Large Lathes grinders and other industrial Machinery. I find these from time to time on EBAY. I could never find one with a low enough voltage to be of any use..I did run across one that like 300 Hosre power at like 240 volts I think...Seemed like something that would be good for using in a Bull Dozer...


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## major (Apr 4, 2008)

steiner said:


> Major,
> 
> Thanks.....quick question....Is this enough data or will I need to record the data at higher values of current at F1-F2? Are we just trying to get the slope of the data or something more specific?
> 
> Rick


Hi Rick,

Sittin' in a motel lobby far from home. Quick look at your data says you'll need to test with higher field current. The slope looks like about 1.5V/field amp. This gives you what they call the air gap line, or represents the flux prior to saturation. What we will need is the slope after saturation and the point or region where saturation occurs. You'll need to run higher current in the field until the curve bends over and assumes a much lower slope.

You should record RPM for each data point to make sure it stays constant or can be used for correction to the V. Also, data for every 1 amp is not required. So, for higher field current, maybe every 5 amps would do. Of course, the more data, the better.

For the higher field current, if you can't get a power supply, try batteries, like 6V, 12v, 18, and so on. You'll need an ammeter and don't leave the high currents on it too long. They'll heat up.

Later,

major

ps....Can you post the nameplate data?


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## JRP3 (Mar 7, 2008)

Georgia Tech said:


> Form the photos these motors look like something from HUGE industrial Machinery, like Really Large Lathes grinders and other industrial Machinery.


For constant speed stationary machines I doubt they'd use series DC motors.
D'oh! Of course these aren't series DC motors so my statement makes no sense.


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## toddshotrods (Feb 10, 2009)

steiner said:


> Major,
> I have an 11" GE motor identical to the one that toddshotrods has...


Did you buy it from MHWC on Ebay? I saw that they sold another GE Model number 8504666 recently, and wondered if someone here won it.

As soon as I get past some chassis issues, I am going to start working on this. I plan to get it moving with a rigged series controller on the arm and a rheostat on the field, but I would like to have the option of getting a medium power SepEx controller while I work on plans for a real race controller.


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## DIYguy (Sep 18, 2008)

Georgia Tech said:


> Form the photos these motors look like something from HUGE industrial Machinery, like Really Large Lathes grinders and other industrial Machinery. I find these from time to time on EBAY. I could never find one with a low enough voltage to be of any use..I did run across one that like 300 Hosre power at like 240 volts I think...Seemed like something that would be good for using in a Bull Dozer...


Lathes don't typically us DC motor, they would use a smaller AC motor and have different drive ratios for spindle speeds. Grinders also use AC motors.... but many drive hydraulic pumps and shuffle the carriage back and forth with it. 

These large DC motors are used to feed huge steel coils into blanking presses at precise speeds.

Cheers.


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## steiner (Dec 8, 2008)

Major,

I finally got around to running some more data. It is all in the attached spreadsheet. It looks to me like this motor is hitting saturation at about 50 amps current on the stator.

The second test I ran was performed supplying the stator with 52.7 amps continuously and then I varied the input RPM to the rotor and measured the corresponding voltage at the armature. From this I got a Kv of 24.2 RPM/volt. I then calculated a Kt of 54 in-oz/amp. Is my thinking correct?

This motor actually didn't have a data plate on it when I received it. The e-bay add gave the following information: 14 Kw, 1000RPM, 36/48 volts, 330 amps. I also measured the resistance more accurately and got .09 ohms for the armature and .28 ohms for the stator.

Todd....Yes, I got it from MHWC. Like you, I originally thought it was a series wound motor.

Rick


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## toddshotrods (Feb 10, 2009)

major said:


> ...ps....Can you post the nameplate data?


From mine since they seem to be identical:
GE Motors
Part # 8504666
AU1840
DC Volts 36/48
SER. # XS-9-1690-YS
KW 14.00
RPM 1000
ENCL OFC
DUTY 60min
CLASS H
AMPS 330
MODEL # 5BT1366B164A


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## major (Apr 4, 2008)

steiner said:


> Major,
> 
> I finally got around to running some more data. It is all in the attached spreadsheet. It looks to me like this motor is hitting saturation at about 50 amps current on the stator.....


Hi Rick,

Nice job on the data. Yeah, I'd say that's about right. I'll say more later.

major


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## Tesseract (Sep 27, 2008)

major said:


> H...What we will need is the slope after saturation and the point or region where saturation occurs. You'll need to run higher current in the field until the curve bends over and assumes a much lower slope....


Quick question - in what region of field current do you typically run the sepex motor? Do you avoid the saturated region completely, or is it okay to enter into there sometimes by a bit or even often-times by quite a lot?


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## major (Apr 4, 2008)

Tesseract said:


> Quick question - in what region of field current do you typically run the sepex motor? Do you avoid the saturated region completely, or is it okay to enter into there sometimes by a bit or even often-times by quite a lot?


Hi Tess,

It depends somewhat on the particular guy that designed the motor in the first place. But the "usual" would be to run the field just below saturation for like the one hour rating, say at about 45 amps on steiner's curve. Here, the thermal suitability of the field "should be" on par with the "rating". This, in my book, would be _full field._

Now you get into the _field Map. _As the armature current (Ia) decreases below rated, it is allowable to run field current (If) below _full field _to field weaken and get speed control above base speed with full armature voltage applied. You probably would not want to run the If above _full field _below rated Ia except maybe for regen. And of course, there would be a lower limit on If.

Above rated Ia, the field should not be weakened, but should be strengthened, in the same proportion as Ia increases. So, if Ia (rated) is 300 amps and If (_full field_) is 45 amps, then when Ia = 600 amps, If should be 90 amps. When Ia = 900 amps, If = 135 amps. And so on.

I would always apply the field strengthening regardless of armature voltage. But never field weaken except when armature voltage is at the max.

That'd be my take on it. I've used commercially available SepEx controls and motors, and programmed them, but have never designed a ground up SepEx system. So, take the statements as opinions 

Regards,

major


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## steiner (Dec 8, 2008)

Major,

I don't have a sep exc controller and would like to simply test this motor to see how it performs. My thinking was to connect a battery across the stator windings that would deliver about 45 amps continuous and then use a chopper controller across the armature windings to vary the speed. Will this work and how would you expect the performance to be?

Do the commercial controllers that are designed for sep exc motors change anything in regards to the stator windings? Do they actually raise the stator current above saturation when the armature current is above the continuous rating as you mentioned previously? What is the benefit of doing this? Greater low speed torque?

Sorry for all of the questions, but I am trying to get my arms around these sep exc motors. Thanks again for the help.

Rick


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## major (Apr 4, 2008)

steiner said:


> My thinking was to connect a battery across the stator windings that would deliver about 45 amps continuous and then use a chopper controller across the armature windings to vary the speed. Will this work and how would you expect the performance to be?


Hi Rick,

Yeah, that will work. Performance will be like a shunt motor with a constant field, like a PM motor. It should do just fine at or below rated load. Watch out for overload. Armature reaction will start to reduce flux as the armature current increases which will reduce torque per amp. The armature reaction also distorts the field pattern which may cause commutation difficulty.



> Do the commercial controllers that are designed for sep exc motors change anything in regards to the stator windings? Do they actually raise the stator current above saturation when the armature current is above the continuous rating as you mentioned previously?


Yes.



> What is the benefit of doing this? Greater low speed torque?


By doing this the SepEx system mimics the series wound motor providing better torque per amp and avoids commutation trouble to a great degree.

Regards,

major


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## yarross (Jan 7, 2009)

major said:


> And equivalent SepEx motor would have a field designed for 30V, 11.7A with a resistance of 2.56 Ohms and 100 T/C. The wire size would have 10 times the cross section as in the shunt motor coil.


Ehm. Not 100 times (if you mean area)?


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## major (Apr 4, 2008)

yarross said:


> Ehm. Not 100 times (if you mean area)?


Hi yarross,

You have detected a discrepancy. In reviewing that post of mine, I see that the nameplate data I used for the example from post #15 was 



> EF(vdc): 300 IF(adc):1.17 RF(ohm):183


So 300 volts, 1.17 amps and 183 ohms do not satisfy V = IR, Mr. Ohm's Law. Must have been a typo on the nameplate data.

So if you substitute 256 ohms for the 183, I think my example holds.

Good job at catching that.  I'll make the correction and site this post.

Regards,

major


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## major (Apr 4, 2008)

yarross said:


> Ehm. Not 100 times (if you mean area)?


Hi again,

Yeah, I mean area. 10 times the cross sectional area gives you 10 times less resistance per unit length. And 10 times fewer turns is 1/10th the total conductor length, so resistance is 100 times lower. The result is the same mass of copper in the field, the same field loss (351W) and the same excitation, 1170 AT.

Regards,

major


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## major (Apr 4, 2008)

major said:


> In reviewing that post of mine, I see that the nameplate data I used for the example from post #15 was
> 
> 
> 
> ...


This was off the nameplate for a GE motor. You'd expect that to be correct. It may be that the field current of 1.17 amps holds true at 300 volts when the motor is at rated temperature. And the field resistance value of 183 ohms is given for room temperature. A ratio of 256/183 = 1.4, which is about what one would expect for a Class F temperature rise change in resistance.


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## pm_dawn (Sep 14, 2009)

Hi !

Regarding larger SepEx and who runs them.
Almost all european(Renault, Peugeot,Citroen) Factory EVs has SepEx motors. In mine for example (Renault Clio Electrique) there is a SepEx ABB motor that runs on about 120v nom. gives about 21kw peak at 2000rpm. It is supposedly a tweaked industrial motor that can be found in large lathes or millers. The controller has a rpm input and controls the field from both accelerator input and rpm input. The controller has a voltage range of 60-160v but is limited to start below 145v. I know that Citroen and Peugeot uses Leroy somer motor of even higher voltage, 180v nom I think.
Pretty much of the Specs for these cars can be found on evalbum.

I have been searching for a high voltage and high power SepEx controler and it seems that there aren't that many around. But I have found two, The Kelly 120v Sepex, which is pretty fair in price but possibly questionable in power, and then an Italian forklift company doing two high voltage/power Sepex controlers. The modell is called Phoenix T62 and T82, the T62 is rated 120v nom and 600A max and the T82 is rated 120V nom and 800A max. I have not yet tested any of there models but they seem to be fairly well built. And about the same price range as the Kellys.
Here is a link to there Website:
http://www.elektrosistem.com/e/p2.htm

They also have a 800A series controller here:
http://www.elektrosistem.com/e/p3.htm


It would be interesting to se any tests of these to see how they perform.

Best Regards
/Per Eklund


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## Qer (May 7, 2008)

Woo. Hello fellow Swede. 

Have you managed to get hold of the specs of the motor to be able to program a new controller then? If so, could you share it since I'm pondering an old Clio (but with the Soliton as controller) as my first EV.


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## pm_dawn (Sep 14, 2009)

Well Most info that can be found on that motor is already presented on the Swedish forum. So you can just take a look there. There is also a measurement done when driving it with the original controller. That info is stored in the document archive of the Swed forum. Then maybe you can ask major to have a look at the numbers to see if it would be possible to program a controller map with only the voltage and accelerator info as input. Otherwise you might know that the ABB has a built in rpm hall sensor.

You could actually call me and we can have a chat about it.
I'll PM you on the Swedish forum.

Regards
/Per


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## pm_dawn (Sep 14, 2009)

Hi !

Here is a datasheet of the Renault Clio motor.

Major: 
What do you think about this motor. As the setup is today it is feed Max 10A for the field and ranging from 180 - 275 as max on the armature. Can this be tweaked do you think. In that case should the field be raised with the same level as the armature current ?

I'm running this motor at 120v nom. The brushes on this one is pretty good I think, four largearea brushes.

We have been poking alittle bit with the original controller. We have been raising the armature current alittle just above 300A, and the car is reported to act much more responsive. But I would like to know if you think we should fiddle with the field also.
I suppose that raising the field current would give us some more torque in the low end, but a lower top speed.
The modifications we are doing is a pure offset adjustment of the currents. We're actually just fooling the cpu in the controller with a lower feedback from the shunts so that the controller puts out more current.
That is why we have not touched the field part yet since it has to be able to go down in current to allow the 4:1 overspeed that is used in the CLio.
We have no possibility to change the Mapping of the field only adjust it up or down.

Best Regards
/Per


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## major (Apr 4, 2008)

pm_dawn said:


> Major:
> What do you think about this motor. As the setup is today it is feed Max 10A for the field and ranging from 180 - 275 as max on the armature. Can this be tweaked do you think. In that case should the field be raised with the same level as the armature current ?


Hi Per,

At first glance, I thought it was a shunt motor. See post #19 for my take on shunt vs SepEx. But further investigation shows a bit of difference. It does appear to me to be designed for over excitation of the field, but not to the degree I have seen on more recent SepEx systems.

One clue. The field power as per the spec sheet is 4.4% of motor rating. This is 2 to 3 times normal for wound field DC motors. Indicating that it may be a state of over excitation. With the specified armature voltage of 105 and field at 90 V, it doesn't leave much voltage headroom for over excitation.

180 Amp current rating for the armature. 300 A for 5 minutes. Not sure what your current limit is. My guess is that with the present set up, 8 to 10 amps field current is cool for 300, maybe 400 amps. Good chance the motor has interpoles and possibly compensating winding to get it to perform acceptably at over load.



> I'm running this motor at 120v nom. I suppose that raising the field current would give us some more torque in the low end, but a lower top speed.


I'm not sure you'd benefit a lot. But no harm in trying it. Watch temperature in the field when raise the current. IsquaredR, ya know.



> it has to be able to go down in current to allow the 4:1 overspeed that is used in the CLio.


You mean like from 8 A down to 2 A field current? Unlikely you see a 4:1 speed difference with a load on the motor.

Regards,

major


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## pm_dawn (Sep 14, 2009)

Well the controller actually lower the field current from 10A down to 2A to allow the motor to overspeed by about 4 times under load.

Here are two sets of measurements done on the Clio with this motor.

Short Swedish electrical dictionary
Fält = field
Hastighet = Speed
Rotor = armature
Ström = current
Spänning = voltage

Best Regards
/Per


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## major (Apr 4, 2008)

pm_dawn said:


> Well the controller actually lower the field current from 10A down to 2A to allow the motor to overspeed by about 4 times under load.
> 
> Here are two sets of measurements done on the Clio with this motor.
> 
> ...


Thanks for the short Swedish lesson. Interesting plots. Guess I'd say the normal field (full field) is like around 3 to 4 amps. From there up to 10A is what I call over excitation. Or likely into saturation. Just guessing. I really don't know much about this motor. But I'd say the actual speed control due to field weakening is less than 2:1. The rest of the speed difference on the plot is due to acceleration. But this is beside the point.

What is it you really want to do? Just increase speed by virtue of increased supply voltage? 

Looks like it works pretty well. Nice regeneration.

Regards,

major


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## pm_dawn (Sep 14, 2009)

Well what I was thinking about was if we should raise the field current any more or if that is enough for any higher armature current. But I guess if you say that 10a field is probably already overexcitation then I will continue to raise the armature in small steps to see what happens. I think that the motor would not die under 400A.

Could you try to evolve the thing about interpoles and compansating windings ?

I think this is what we have in these motors, they seem to be connected somehow between the field and armature, because if the field fuse blows the motor will turn very slowly on only armature feed. That would imply that there is somekind of connection in the motor that somehow feeds the field a litte from the aramature.

Best Regards
/Per


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## major (Apr 4, 2008)

pm_dawn said:


> Could you try to evolve the thing about interpoles and compansating windings ?


Hi Per,

Without going too deep into motor theory, this is the deal. Likely you have a 4 pole motor. These are the main field poles. Located at 90 degrees around the inside of the frame. Each has a field coil around it. The field excitation (mmf) is responsible for the main field flux.

The armature is composed of conductors which lie in the main field flux path essentially in the air gap. The interaction of armature current and the flux produces torque, as well as generates voltage. All is well, except that by virtue of current flowing in the armature conductors, the armature itself establishes a magnetic field. This armature magnetic field is in quadrature with the main field. So it adds to the main field on half of the main pole and bucks it on the other half.

The result can be described as armature reaction and armature distortion. This isn't likely to 100% technically accurate, but think of it this way. This armature field causes a distortion of the main field which results in flux in the interpolar region, called the neutral zone. Ideally, one wants no flux here so that the armature coils can be commutated with no induced voltage from field flux. 

Interpoles are narrow pole pieces placed inbetween the main field poles in the frame. They have windings on them called comm coils. These are excited by armature current and provide mmf to force the flux in the neutral zone to the proper level to get acceptable commutation. They do not contribute to torque production. And they do little if anything for gross armature reaction.

Armature reaction causes a weakening of the main field mostly evident at high armature current levels. This results in a reduction of torque per amp. Compensating windings help counteract this. These are conductors (or coils if you like) placed in slots in the main field pole faces. They run axially, parallel to the shaft. The coils or conductors are also connected to the armature circuit so they carry armature current and their strength is proportional to armature current. Compensating coils reduce or negate the effects of armature reaction and keep good torque per amp at overload.

Interpoles are uncommon in small motors, as well as compensating windings. Neither contributes directly to torque production but have resistance which is a loss and take space otherwise available for material which could produce torque. And they are costly.

I cannot tell from the drawings of the motor if it in fact has these features. But was guessing on the fact that ABB is known for large motors where such features are common. Because both comm coils and compensating windings need armature current, there will be a connection between the brushes (A terminals) and the field structure.

Probably more than you wanted to know 

See http://zone.ni.com/devzone/cda/ph/p/id/49 figure 5.23 and 5.24. 

major


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## DavidDymaxion (Dec 1, 2008)

My Kostov sepex motor does this, too. You are right that a compound wound motor would do this. Another possibility is there is some residual magnetization. Since the field tends to get current in just one direction I'd think it would tend to get a little permanent magnetization. Major have you seen this?


pm_dawn said:


> ... I think this is what we have in these motors, they seem to be connected somehow between the field and armature, because if the field fuse blows the motor will turn very slowly on only armature feed. That would imply that there is somekind of connection in the motor that somehow feeds the field a little from the aramature. ...


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## major (Apr 4, 2008)

DavidDymaxion said:


> Major have you seen this?


Well, kind of. A couple of things. Yes, the field magnetic circuit in the DC motor will retain residual magnetism, usually very weak and probably not responsible for causing rotation of an excited armature.

However, what could do this is the armature field itself. As I discussed above, if the armature has current flowing, it produces its own magnetic field. Now if the surrounding steel structure is not perfectly symmetric, or if you start rotation, it will rotate in its own field without main field excitation.

Don't get any ideas  Nothing useful here  Just an oddity 

Regards,

major


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## pm_dawn (Sep 14, 2009)

major said:


> Hi Per,
> 
> Without going too deep into motor theory, this is the deal. Likely you have a 4 pole motor. These are the main field poles. Located at 90 degrees
> .snip....
> ...


Really interesting, I just need to brush up on my electrical english and read this bit acouple of times to perhaps get the picture. But as we say "still confused, but on a higher level"

Many thanks Major.

I really hope Qer and Tesseract makes a solition sepex. That would be so cool, I guess i will never afford one, but still cool.

Regards
/Per


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## DavidDymaxion (Dec 1, 2008)

How's this for a restatement in other words: The armature electromagnets want to line up with nearby lumps of iron, in this case the field poles -- kind of like an inside-out switched reluctance motor. So you are right, I see that this would not require residual magnetism but would make the motor rotate.


major said:


> Well, kind of. A couple of things. Yes, the field magnetic circuit in the DC motor will retain residual magnetism, usually very weak and probably not responsible for causing rotation of an excited armature.
> 
> However, what could do this is the armature field itself. As I discussed above, if the armature has current flowing, it produces its own magnetic field. Now if the surrounding steel structure is not perfectly symmetric, or if you start rotation, it will rotate in its own field without main field excitation.
> 
> ...


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## green caveman (Oct 2, 2009)

steiner said:


> I finally got around to running some more data. It is all in the attached spreadsheet. It looks to me like this motor is hitting saturation at about 50 amps current on the stator.
> 
> The second test I ran was performed supplying the stator with 52.7 amps continuously and then I varied the input RPM to the rotor and measured the corresponding voltage at the armature. From this I got a Kv of 24.2 RPM/volt. I then calculated a Kt of 54 in-oz/amp. Is my thinking correct?


Would you be willing to provide more details on how you did these tests? Equipment used, setup, etc.

It seems that using a Sepex is a good basis for a regen system, but that running these tests to get the data is about the only way with an unknown motor.



steiner said:


> Todd....Yes, I got it from MHWC. Like you, I originally thought it was a series wound motor.


He's still listing motors. Do you have any way to recognize sepex vs. series?

Thank,


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## major (Apr 4, 2008)

green caveman said:


> Do you have any way to recognize sepex vs. series?


Hi green,

Clue #1: Field terminals are smaller than armature terminals.

Clue #2: Field terminals are labeled F1 and F2, Armature is A1, A2. Series motors typically use S1 and S2 for the field.

The above may or may not apply. Depends on the motor.

Clue #3: Wire shape and size wrapped around the field poles. Series motors typically have rectangular shaped ribbon wire for the field coils. SepEx typically have round wire field coils. Can be fairly large gauge wire, but always round from what I've seen. A lot of times the field coil is wrapped in insulation. But usually the wire can be seen where it connects to the terminal. 

The above is not an absolute. But I'd give it a 99 on the motors you're likely to see.

Clue #4: Resistance, resistance, resistance. On the motors you're concerned with, the series field resistance will be on the order of milliohms, maybe as high as 10 or 20 milliohms. This will likely read as a short circuit (zero ohms) on an ohm meter or multimeter. A SepEx field will likely read between one ohm and maybe as high as 100 ohms. Most likely between 0.5 and 5 ohms. But on the order of like 50 to 100 times higher than a series field.

Unless you can get in and count the number of turns on the armature and field, clue #4 is the most reliable.

Regards,

major


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## steiner (Dec 8, 2008)

caveman,

I did these tests by putting the motor in a lathe to rotate the armature. I then connected one DMM across the armature terminals and one DMM across the field terminals. I originally assumed that the lathe would keep the armature rotating at a constant speed but Major recommended that I actually measure the RPM of the rotor. I used a digital tach and recorded the RPM at different field voltages. As you can see by increasing the current through the field, the RPM of the armature will be reduced. I initally tried using an adjustable power supply for the field voltages but it only went up to 20 amps. I then replaced the power supply with actual 90 Ahr cells to supply the current. This is why the current is graphed in steps. I would simply add another cell to the battery string to increase the voltage which in turn increases the current through the field connection. I measured the current with a hall effect current sensor.

I hope this helps....

Rick


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## Qer (May 7, 2008)

major said:


> Clue #4: Resistance, resistance, resistance. On the motors you're concerned with, the series field resistance will be on the order of milliohms, maybe as high as 10 or 20 milliohms. This will likely read as a short circuit (zero ohms) on an ohm meter or multimeter. A SepEx field will likely read between one ohm and maybe as high as 100 ohms. Most likely between 0.5 and 5 ohms. But on the order of like 50 to 100 times higher than a series field.


It's tricky to measure low resistances with your average day el cheapo multimeter since the wires themselves usually are a few hundreds of mOhm, so a simple and fairly reliable way to detect if the field is in the mOhm or Ohm range should be to connect the field winding in series with a 12 Volt 55 Watt lamp bulb and then connect them to a 12 Volt battery (but leave the armature disconnected to avoid that it starts to spin). If the voltage over the field is very low (something like 0.1-0.2 Volt) then it's a series wound but if the voltage is in the Volt range (about 2 Volt and up) it's probably a SepEx.

Don't take my word for it without majors blessing, but it SHOULD work!


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## major (Apr 4, 2008)

Qer said:


> It's tricky to measure low resistances with your average day el cheapo multimeter since the wires themselves usually are a few hundreds of mOhm, so a simple and fairly reliable way to detect if the field is in the mOhm or Ohm range should be to connect the field winding in series with a 12 Volt 55 Watt lamp bulb and then connect them to a 12 Volt battery (but leave the armature disconnected to avoid that it starts to spin). If the voltage over the field is very low (something like 0.1-0.2 Volt) then it's a series wound but if the voltage is in the Volt range (about 2 Volt and up) it's probably a SepEx.
> 
> Don't take my word for it without majors blessing, but it SHOULD work!


Sure Qer,

Something like that will work just fine. A lot of multimeters have milliVolt scales. So, if you hook the motor field into a circuit and know the current, just use Ohm's Law and calculate the resistance. So if you use a 12 volt battery and a 12 ohm resistor you'll get about one ampere. Even with a field having a resistance of 0.010 ohm in series with the resistor, it won't make that much difference. So measure the voltage across the field. It will be like 0.01 volts or 10 mV. Bingo. You got a 10 mOhm field.

Regards,

major


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## felonymatarspike (Oct 12, 2009)

Has anyone progressed with the 11" sep-ex GE motor (8504666)? I own one and am preparing to purchase the Kelly KDC72603 controller. I am concerned about being able to determine the field map. I was going to contact Kelly to see if they know of anyone doing this for this motor.


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## green caveman (Oct 2, 2009)

felonymatarspike said:


> Has anyone progressed with the 11" sep-ex GE motor (8504666)? I own one and am preparing to purchase the Kelly KDC72603 controller. I am concerned about being able to determine the field map. I was going to contact Kelly to see if they know of anyone doing this for this motor.


Check back through the thread - Rick has figured out the field map for this motor. 

Please keep us updated on your project. I'm planning just about the same configuration - same motor and controller manufacturer, although I may go with a slightly smaller (lower cost!) controller for a Suzuki Sidekick conversion.


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## toddshotrods (Feb 10, 2009)

green caveman said:


> Check back through the thread - Rick has figured out the field map for this motor...


 Is that the actual field map, or the data needed to develop it?

It's great to see that there are a number of people popping up with this same motor.


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## green caveman (Oct 2, 2009)

Todd,



toddshotrods said:


> Is that the actual field map, or the data needed to develop it?


Is that the same question as what do we all do with this information that Rick has so kindly discovered for us?

I was under the impression that some part of this was used to configure the controller, so I read the manual for the Kelly KDC controller. They have a step-by-step configuration for the controller here, similar page for the smaller (500A) KD controllers here.

The only step that seems to relate to sepex is step 6 on the KDC, step 3 on the KD where it asks for:

_Field Current Percent (with slider 0-100)
"Set field current to percentage of max field current allowed by controller"
Field Weakening (enable/disable)
"If enabled, the controller will reduce field current if output voltage reaches 90% and throttle is higher than 90%. The minimum field current is 50% of set value"
Field Switch (enable/disable)
"If disabled field function will be closed. So controller will be viewed as the ordinary motor controller. If enabled, field function will be opened"._

Did I miss something or are these really the configuration parameters for sepex?

While I'm reading the manual, since, I assume that the reason for running sepex is to get regen, can anyone help me interpret step 4?

_Regeneration (Enable/Disable)_ - so far so good.
_Braking Switch (Enable/Disable)
"If enable, turn off throttle and turn on brake switch will start regen"_
OK, I think this means that if I have a brake switch connected (presumably possible to wire are part of the brake lights circuit). Then as soon as someone hits that switch I'm in regen.
_Regen Current By Brake Switch On (percent slider)
"Max regen current can be limited to the percentage of max signal from brake sensor"_
I lost it at the "brake sensor" - but there's more to follow, could just be bad organization of the page?
_"Brake Sensor Type" (Drop-down with "Not Used" as default.
"It's to vary regen on time. Please choose "Not Used" if you do not use analog brake sensor. You should turn on brake switch to start regen, then vary regen with the signal._
Then we have:
_Brake Sensor Starting Point (with percent drop-down, not a slider, how's that for user interface design - 20% selected)
Brake Sensor Ending Point (% drop-down 80% selected)_

If I understand this, which seems quite unlikely, it means that I can install a digital brake switch. Switch the switch (with the brake pedal) regen will then do its thing up to the max current I specified ("Regen Current by Brake Switch On"). If I'm feeling inspired, I can install an analog brake sensor (presumably also attached to the brake) which would then increase the current as the brake is pushed harder. (As I write that last sentence, it seems that might be a good thing and worth the effort).

Thanks,


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## JRP3 (Mar 7, 2008)

Could the "analog brake sensor" be something similar to a 0-5k pot?


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## steiner (Dec 8, 2008)

caveman,

Here is my understanding of this motor. Hopefully Major will chime in if I have something wrong.

It looks like the field goes into saturation at about 50 amps for these motors. Therefore max torque will be delivered when the field is held at a constant 50 amps. Obviously torque will go up and down as you vary the armature current which is what your pedal will tell the controller to do. The only reason you would want to decrease the field current (field weakening) is to allow the motor to rev to a higher RPM. This higher RPM will occur at a reduced output torque which will eventually match the required torque for that speed and you will therefore not go any faster. The downside to this is hills will reduce your speed more than when the field is receiving 50 amps.

I believe you have a correct understanding of the Kelly controller in regards to regen. You can activate it using a switch and get a fixed percentage of regen or you can activate it via an analog switch and vary the amout of regen. I am using the first configuration on another vehicle I have that uses PM motors and it works well. My problem with the analog approach is that the brake pedal will only travel a short distance before the mechanical brake starts working and you never really get into the high percentage of regen. I just adjusted the percentage of regen when activated by the switch until I was happy. Once you get use to it you will use regen to do 90% of your braking requirements yet the mechanical system is available for the panic stops.

If you go the Kelly route, let me know how it works out. I'm not a huge fan of Kelly controllers but as long as you run them at about 80% of their rated value and provide plenty of cooling, they are OK.


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## Guest (Oct 13, 2009)

JRP3 said:


> Could the "analog brake sensor" be something similar to a 0-5k pot?



Yes it is. I will be testing both methods of regen.


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## green caveman (Oct 2, 2009)

steiner said:


> It looks like the field goes into saturation at about 50 amps for these motors. Therefore max torque will be delivered when the field is held at a constant 50 amps.


So, the only value from your spreadsheet that we really care about is the "break" in the curve at ~50A?

That would make sense in that the only parameter in the Kelly controllers is the "Field Current Percent". This is described as the "percent of max field current allowed by the controller". Unfortunately, the manual for the controller does not specify the "max field current", but presumably that can be had from Kelly.



steiner said:


> The only reason you would want to decrease the field current (field weakening) is to allow the motor to rev to a higher RPM. This higher RPM will occur at a reduced output torque which will eventually match the required torque for that speed and you will therefore not go any faster. The downside to this is hills will reduce your speed more than when the field is receiving 50 amps.


But the field weakening only takes place "if the output voltage reaches 90% and throttle is higher than 90%". So this may have some benefit as you describe. When you have the pedal to the metal the field weakening will occur and let you get some more speed out of the motor. As you say, with the commensurate loss of torque this may, or may not, get you more vehicle speed, but it's there to be experimented with. The disadvantage is not there since when you take your foot of the pedal (< 90%) the field weakening will no longer be in effect.



steiner said:


> I just adjusted the percentage of regen when activated by the switch until I was happy. Once you get use to it you will use regen to do 90% of your braking requirements yet the mechanical system is available for the panic stops..


Did you put the switch on the brake, so you have to touch the brake at least to get regen to kick in, or on the accelerator so that regen kicks in like an ICE whenever you take your foot off the gas?

It would seem that you could also put the analog brake switch (which is 0-5V) at the top of the accelerator pedal. If you're just likely resting your foot on the pedal you'll get some "engine" braking, once you take your foot off it and over to the brake you're at max regen. Might feel a little odd or take some getting used to.

My one concern about regen is that we live in a hollow in a mountain. The route where we really need the braking is a 3-4 mile quite steep downhill stretch, but it's fairly close to the start of the journey so the regen make kick out because the batteries are fully charged meaning you'll end up standing on the brakes (I followed a truck with smoking brakes doing just that yesterday). Only experience will tell.



steiner said:


> If you go the Kelly route, let me know how it works out. I'm not a huge fan of Kelly controllers but as long as you run them at about 80% of their rated value and provide plenty of cooling, they are OK.


Kelly seem to offer some good features at a (relatively) low cost. They have 72V sepex with regen 500A (1minute - 200A continuous) for $599 and 600A (1 min - 240A continuous) for $799. I haven't bought the controller, so I'm not committed to Kelly yet, but my first pass over the manufacturers says that those prices are hard to beat. It would be good to have some real street pricing for controllers. Any particular recommendations of who I should chase down for pricing?


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## steiner (Dec 8, 2008)

Yes, the 50 amps seems to be the key value for the field. 

I actually used the high pedal switch on the accelerator. I put it there as a safety switch that prevents the controller from powering up if something is pressing the accelerator. Kelly controllers have a provision for this. Since the switch was already mounted, I also used it as the switch to activate the regen. It only activates when the pedal is completly released. When you want to coast, you simply leave your foot on the pedal slightly to keep the switch from activating. 

The problem that I ran into with the analog pot for regen had to do with the amount of rotation of the pot. My accelerator pedal only moves through a 30 degree arc from completly released to full throttle. My brake pedal is even less.

Kelly does offer some good features at their price. I went through 6 controllers initially before I got one to work. To get the last one to work I had to go to a higher current rated controller and also configure it to only 80% of max output. My biggest issue was dealing with Steven. He is very quick to make everything look like your fault. I realize he has to deal with many different people with various backgrounds, but I always explained in great detail what I was doing and simply implemented his recommendations. I think they brought their product to market a little too early and used the market as their test bed. Hopefully they have resolved most of their issues. 

There are only a few other controller brands that I know of that will work with sep exc motors. Not all of them have programmable field currents and none of them offer the armature current that I need (600A) other than Kelly.


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## green caveman (Oct 2, 2009)

steiner said:


> I actually used the high pedal switch on the accelerator.
> [..]
> The problem that I ran into with the analog pot for regen had to do with the amount of rotation of the pot. My accelerator pedal only moves through a 30 degree arc from completly released to full throttle. My brake pedal is even less.


Seems that the two are not mutually exclusive. That is, the amount of regen in controlled by the pot and activated by the switch.

I'm thinking that around town you may want less regen, but on a downhill run you want to max out the regen and minimize the brake use.

Makes me wonder if a pot on the dash would work. Around town set it low/medium. When you go downhill use it to the max to control your speed (and max. charge, but that's just a side effect).

[OffTopic]
I'm concerned about that hill! Not only getting down it without burning the brakes, but back up again - it's about a 800ft climb. It's one of the design constraints of the conversion, it should make the 25 mile RT that includes that hill. I wish I had a good feel for how much effective range hills cost you. On the plus side, the hill has a "crawler" lane so it can be climbed slowly so saving energy. (The ICE metro is at 35MPH in 3rd gear by the time you get to the top - 25 in 2nd if you're pulling a boat, but that's another story). I realize that more/better batteries will help, but there's a cost in oversizing, since this is the most demanding run required of the car and it only needs to do it once every week to two weeks.
[/OffTopic]


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## JRP3 (Mar 7, 2008)

Getting down the hill is easy, just don't fully charge the pack at the top to leave room for regen.


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## steiner (Dec 8, 2008)

GC,

I am fairly sure the two configurations you mentioned for the regen can only be used seperately. When you use the switch method, you need to configure the software to tell the controller what percentage of regen you want. This can only be changed by going into the configuration file. The second method (pot) simply changes the amount of regen in real time. If the pot is zero.....zero regen. If the pot is 5K.....full regen. Mounting the pot on the dash would work but you would need to turn the pot by hand every time you wanted to slow down via regen. Obviously you would then need to turn it back to zero when you wanted to speed back up. It could be done but ...... one hand steering, one hand on the pot, one foot on the accelerator, and one foot on the brake. Sounds kind of busy to me. You might want to ask Steven about all of this though. There might be a way to do what you want (using the pot with the switch) that I am not aware of.


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## green caveman (Oct 2, 2009)

What I'm thinking at the minute is that I should buy a cheap, used 36V/400A Curtis sepex controller and three of the cheapest (starter?) batteries I can find.

If I can do this for $200 or so, it would let me plumb the unseen depths of my ignorance very inexpensively. I'd end up with an NEV with a top speed of (maybe) 20-25mph and a range of 3 or 4 miles - but it would run.

Most of the conversion would be complete, removing the ICE, adapter for the motor, etc. etc. Although the batteries racks/placement would have to wait. A controller and battery upgrade would make it a real vehicle.

It would be a lot easier, for me, to spend $2K+ (new, bigger, controller & batteries) on a running, working vehicle than on a potential project sitting in the driveway, even though I'd throw away the initial controller and batteries. I might be more willing to spend more money on better components (96+V, etc. batteries big enough to make it up THE hill) than I am now.

Has anyone worked with the low-end Curtis sepex controllers? I gather that the challenge might be programming them without spending $600 on a hand-held programmer. Or is it possible that I wouldn't care? I don't need performance, but is it possible that I'd damage the motor if the controller isn't programmed correctly?

Is there a different controller that might be a better choice (EV1, some other forklift controller)? Do you think MHWC might be able to find one if I know what questions to ask? (The Hyster forklift the motor came from must have had a controller).

Do anyone with experience feel that my approach is good/bad? Will the vehicle even move? It would seem to me that the "upgrade" once it's all running would be relatively simple - that is, the NEV/testing stage is not a major waste of effort.

Thanks, and thanks for letting me bounce the idea off the group even though it's not really on the topic in question.

For the record, the motor is the 250lb motor that the major topic of this discussion and the vehicle is probably going to be a Suzuki Sidekick 2D 4WD soft-top (I've bought both of these, but haven't actually seen either!).


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## major (Apr 4, 2008)

green caveman said:


> What I'm thinking at the minute is that I should buy a cheap, used 36V/400A Curtis sepex controller and three of the cheapest (starter?) batteries I can find.
> 
> Has anyone worked with the low-end Curtis sepex controllers? .


Hi there green,

I used the Curtis 36/48V 500A SepEx on some utility trucks with 6.6 inch motors. The company bought the programmer so I can't lend it out. 



> I gather that the challenge might be programming them without spending $600 on a hand-held programmer. Or is it possible that I wouldn't care?


Yeah, you'll need that.



> I don't need performance, but is it possible that I'd damage the motor if the controller isn't programmed correctly?


More likely damage the controller than the beast of a motor. Or get crappy performance. Or not work at all. The programmer also monitors things, so you really need it to set up correctly.



> Is there a different controller that might be a better choice (EV1, some other forklift controller)?


I like the Sevcon MilliPak as much or better. You'll need a PCpak programmer for that.



> Do anyone with experience feel that my approach is good/bad?


Makes sense to me 



> Will the vehicle even move?


I suspect it would in low gear.

Regards,

major


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## JRP3 (Mar 7, 2008)

With a Kelly controller I don't think you need a separate programmer to change things. Might be cheaper in the long run.


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## Guest (Oct 15, 2009)

JRP3 said:


> With a Kelly controller I don't think you need a separate programmer to change things. Might be cheaper in the long run.


All you need is to have the proper cable for your computer application, serial or usb and the program from Kelly's site and power up your controller and hook up your computer and you are good to go. It is easy to configure. Program is free but the cables Kelly has are the ones you should get. Others had trouble with other cables and the ones from Kelly work just fine. I have used both the serial and usb and both work equally well. 

Pete


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## Guest (Oct 15, 2009)

With the kelly you can only use either the switch percentage mode or the pot mode for regen. Not both at once. Though I never tried both at once. Guess a call, ooops, email to Steven is in order. 

Pete


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## green caveman (Oct 2, 2009)

How about the 36V GE controllers similar to the ones in the GEM/Zenn? They seem to be programmable with "GE Sentry" which is relatively inexpensive (~$80 with the cable). There's also some suggestion that those will go to 48V.

There seems to be 72V 500/50A versions of these controllers used in forklifts if anyone has a lead on low-cost forklift parts. 

I found a site with the Curtis PC software for $45, but that still leaves the cabling problem. Plus it's out of stock with an 8-week lead which may be the same as "never". If the cable is really a TTL RS232 then that's an easily solvable problem, but it seems to be more than that. I'm tempted to try it, but I think it's probably a time-sink.

I looked at the Kelly controllers. The low voltage Curtis, even sepex, are all over EBay for < $100 (less if you don't care if it works!). The Kelly controllers aren't as common. If you go new you're looking at $300+ for just a test controller (48V 200A or so) which, to me, is out of the throw away price range. Similarly for the Sevcon MilliPak


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## todayican (Jul 31, 2008)

Has anyone had any experience with this motor: ES-32A motor from D&D

And / or this controller: http://www.newkellycontroller.com/product_info.php?cPath=55&products_id=415

Do we have a match? Will this motor stand up to 300 or 400a at 120v?


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## todayican (Jul 31, 2008)

Ok, this may be a dumb question, but I just spent an hour with a golf cart guy talking about how this motor: http://cgi.ebay.com/36-48-VOLT-Golf...ltDomain_0?hash=item27ac4b7469#ht_8104wt_1049

Is known to power 48v golf carts up to 60mpg (but why??) 

so a motor like this is well suited to a 48v 600a controller like the alltrax dcx, a) would it be ok with 120v and 400a? 300a?

and b) would it be as simple as pairing it with the 120v 400a kelly and setting some parameters? or is there a lot more to it then that?


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## green caveman (Oct 2, 2009)

todayican said:


> Has anyone had any experience with this motor: ES-32A motor from D&D
> 
> And / or this controller: http://www.newkellycontroller.com/product_info.php?cPath=55&products_id=415
> 
> Do we have a match? Will this motor stand up to 300 or 400a at 120v?


No Regen?
http://www.newkellycontroller.com/product_info.php?cPath=55&products_id=416


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## green caveman (Oct 2, 2009)

todayican said:


> Is known to power 48v golf carts up to 60mpg (but why??)


The forklift motor thread (all 80+ pages) is worth reading even if you're not planning on using a forklift motor. There are some very knowledgeable people contributed to that thread.


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## major (Apr 4, 2008)

todayican said:


> Is known to power 48v golf carts up to 60mpg (but why??)


Why? Maybe downhill. Seems like to me that would be enough of overspeed to throw the motor apart on the standard axle gear ratio. But I don't know for sure. Or it could be that you can do 60 mph a few times and then your brushes are smoked. Got no idea. Can this guy guarantee you 1000 hrs of 60 mph in the golf cart with his motor?



> so a motor like this is well suited to a 48v 600a controller like the alltrax dcx, a) would it be ok with 120v and 400a? 300a?


Well suited? Says the guy trying to sell it to you  I don't know for sure. The motor looks a lot like the D&D SepEx I have used on Ut Trucks. Good motor. I used a 500 amp Sevcon. Don't know I ever saw more than 300 amps, even pulling a ton up a steep incline. No problems with my set up. And it wasn't a ventilated motor. 120 V? You'd likely smoke the brushes quickly unless you advance them. And at that voltage, any reasonable current is going to result in motor overspeed, IMO.

Looks like a good motor. But don't ask too much of it 

Regards,

major


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## green caveman (Oct 2, 2009)

Todd,

It seems that you managed to find a splined hub that fits these motors:



toddshotrods said:


> I just ordered the Massey Fergusson PTO disc, for the splined hub, from ssbtractor.com.


Do you happen to know the part number? There seem to be about three or four that would match your description (the one that seems closest is $43.55, which seems to be about what you paid).

How did the hub work out? To me it seems that it should be a major time/money saver in building the coupler, but maybe your experience say otherwise.

How did you end up supporting the end of the transmission in your coupler?

Thanks,


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## toddshotrods (Feb 10, 2009)

green caveman said:


> Todd,
> 
> It seems that you managed to find a splined hub that fits these motors:
> 
> ...


Yup, that's the one. I used "*Massey Ferguson Rigid PTO Disc - *Product ID: MFRPTODZ"

Here's the page on their site

The hub is a perfect fit, but it is not a press fit. It's a slip fit, meaning it was designed with a little extra clearance, so it can move on the shaft. There were a couple suggestions for using it in a coupler in my build thread. I think on this page.

I decided to run direct as I am really just building a street-legal race car, that is also going to be light enough to perform well without the transmission. I am going to mate the PTO disc's splined hub to the end of a driveshaft, which will then plug right into the back of my motor. The slip-fit ended up being perfect for me.

Hope this helps.


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## puddleglum (Oct 22, 2008)

Hi guys, I'm going to take a chance and revive this thread because a lot of the previous information directly relates to my concerns. Hopefully someone in the know will still chime in. I have an old 11" Kostov sepex motor that was in a conversion from 20+ years ago that I'm hoping to rebuild and get back on the road at some point. Juria from Kostov Motors was very helpful in helping me identify it and suppling motor data, but I'm having a little trouble interpreting the specs. I have a few ideas, but not sure if I'm right. also, not sure how they would translate to controller settings for the field map. No data plate on the motor itself. Here is what I got from Kostov:
P = 20 kW ; I a = 256 A / current / ; U = 96 - 0,023 . I a ; rated speed = 4000rpm; S2-60min
I sep = IF = 0,057 . Ia = 14 A
I get the Ia = 256 and the 96 volts. What is the u = 96 - 0.023 and the IF = 0.057 and the Ia = 14a? I'm really confused as to what they are telling me. Does anyone know for sure? The motor has interpoles. Controller is a Zapi Sem-3; 96v - 500a.

Is this data enough to accurately set up a field map or would it still be advisable to test and plot a no load Saturation curve like major described on page 2 of this thread?
I guess I'm trying to determine if this motor could still be a viable option for this car. It appears to still be in good condition. 
I also asked Juria about peak limits for the motor based on the curve, in case I were to do something different for a controller, here was his reply.

"Under normal rpm and load, even 192V do not present a commutation problem.
On this old commutator, anything above 4500rpm is a risk.
Of course you can control rpm by overloading the field but this works only for a while.
If you get a big disbalance between field and armature fields, one gets sparkling again.
In my opinion, you can overload the field not more than 2.5 times and aim at 4500rpm/600A for not more than a minute at whatever voltage you get it.
This is not a 100% guarantee motor will be OK J"
Apparently the motor is most efficient really close to red line.


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## puddleglum (Oct 22, 2008)

Is it likely that the 0.023 Ia after the 96v is armature amps/volt? Could the IF=.057 be percentage of armature current. I have no idea about the Ia= 14a. Hoping someone knows.


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