How to identify a Servo motor

[Mr.Chips]

I have seen some motors that aren't steppers because I don't feel any magnetic resistance when I turn the shaft.
I'm wondering if they might be Servos?
They don't look like normal AC or DC motors as they are rather a larger dia (about 8") for their length and the outside has a square shape with heavy fins that are made of sheet metal.
They have a very short shaft with a three fingered rubber bumpers that are half of the connection to what ever they were driving.
The manufactures name was missing. There was a large printed table of voltages, again I didn't note any of them.
Sorry I didn't count the wires.
Next time I'll take my digital camera.

What do I have to look for to identify the motor type?
I have a multimeter.

Thanks
Hager

[balsaman]

They could posibly be 3 phase motors. More info would be good. Almost imposible to identify by the description.

Steppers generally have 4, 5, 6 or 8 wires

Servos 2 or 3, generally with an encoder mounted on the back.

Eric

[Mr.Chips]

The back has a fan that is inside sheetmetal.

I get back there in a couple of more days and get more info.
Oh yes they were pretty light for their size.
Hager

[balsaman]

Probably just regular AC motors.

Eric

[bunalmis]

You can apply a small voltage for any coils. (12v)

If motor turns big step and locked this motor probably is
a reluctance or brushless dc motor.

If you can not see any movement at the shaft this may be asynchron motor

[Mr.Chips]

Bunalmis
That is a simple test, thanks for the tip.
Hager

[Mr.Chips]

I got a chance to photograph the motor, however the shot with the voltage matrix wasn't good enough to read the plate. Willpost photos.
Possibly someone can identify.

[Mr.Chips]

Here's another view.