motor types - was Re: (ET) E12S and a curtis controller??

["SteveS" <ssawtelle fcc net>]

>Can someone provide a concise summary of the characteristics of the E12,
E12S, 15 and 20??
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Been away for a few days and didn't see if this was answered so please
forgive any redundancy....

As I understand it, the E12S and E15 are identical except for the field
weakening. Motor is the same. You could add field weakening to the E12S if
you really wanted to , it's just extra series resistance in the field
circuit.

The E12 I don't know. Wiring is quite different, but a look at the 
schematic
should show what type of motor it is fundamentally.

I have an E20, but haven't been into the wiring too much YET, but it is a
shunt motor.

I think all these motors are basically shunt type, just different sizes. I
believe they also have some series field which, as I believe someone 
stated,
acts to keep motor  speed constant under load.

The snowblower (and tiller I think) motors are basically series wound with 
a
small shunt winding for the same purpose? The shunt winding shunts only the
armature  (the series winding is in series with the combinbes 
armature-shunt
field) - as I recall.