# Series Motor with Sepex controller



## major (Apr 4, 2008)

Bochek said:


> Sepex controllers control the field separate from the armature right?


Hi Bochek,

Yes, that is correct.



> And according to this doc: http://www.evparts.com/img/mt2116%20Outline.PDF
> 
> ADC motors have separate connections for field and armature windings.


Yes, they have separate connections for the field and armature. But it is a series motor. It has the separate armature and field terminals so that it can be reversed.



> So they should work together?


No, series motors won't work with SepEx controllers.



> Why is everyone buying special "SEPEX" motors?


Everyone? Most guys use series wound motors. There are some who use SepEx.

There is a basic difference in the field coils for series and SepEx motors. And that accounts for about 10 times more field current required for the series field than the SepEx field.

You need to consider the motor and controller as a system. And there is a big difference between the series motor controller and the SepEx controller. The series motor controller requires that the motor be a series wound motor with the field in series with the armature. And the armature and field current is the same. For instance, 500 amps.

The SepEx controller is made to supply the armature with 500 amps and the field with 40 or 50 amps. So it needs a special motor with a field winding with like about 10 times more turns than the series motor.

In theory you could take a series motor and design a SepEx controller for it which would do 500 amps for the armature and 500 amps for the field separately. But such a controller would be very large and expensive. Just not a wise choice.

The SepEx controller is actually 2 controllers in one box. An armature controller (500A) and a field controller (50A). The lower current rating for the field controller makes the SepEx economically feasible.

Hope that explains it for you.

major


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## Guest (Sep 26, 2009)

Because the fields for SepEx are fine wire that takes just a tiny bit a power to operate. The armature is about the same for both series and sepex. So a SepEx controller controls the field with low amperage power and the armature with high amp power. It can also provide regen if the field is kept under power and the movement of the vehicle will spin the motor and because the field has power it will begin to generate power and slow down and pump power back to the batteries. Simple and easy. If the motor has interpoles it will be better. A normal series has way too much amperage flowing to make it work with a SepEx controller. SepEx allows different power requirements. My Kaylor Motor is a special SepEx motor and it is also a drive and generator. High RPM and will regen properly. I am testing a special SepEx controller for these style motors as they are not a normal SepEx motor but they are SepEx and not series. They are also not compound. Good for light weight VW buggies. If the controller works as planned I am going to ask if they could try a 96 volt version and also a 120 volt version. My controller is 72 volts and 600 amps. 

Pete 

PS. The motor is going back into the Ghia for testing while I replace a bearing in my old GE 9" motor. I am also going to replace the brushes and clean the motor. Motor is apart right now. My other GE motor is going up for sale along with my 72 volt controller that I used in my Ghia for awhile. It will push a stock steel body Ghia to 65 mph. If used in a Bug or Buggy it will do much better but that is fine for most applications.


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