Hello. I recently acquired a DC motor, aprx 5 hp, formerly used in a golf cart. As you can see from the photo there are 4 terminals (1 on left side, 3 on right). How do I power this? Which terminals receive which polarity? I tried applying 12v in a few combinations and got a few sparks, but it did not spin. The former owner assured me it did work for him but couldn't remember how to wire it. Any suggestions?
Thanks.

 

Hi,
if no labels given in the outside body.it is better to open up the case and see the circuit.
from looking inside and see how is the wiring goes on,the circuit can be known.
Lets somebody who have a knowledge in electronics circuit can look that.

 

You have a wound field motor, each has to be powered separately, the commutator pair control the rpm.
The higher the field current the higher the torque, but at a cost of lower rpm.
It is going to spark a bit if not securing the wire to the terminals.
Max.

 

If this doesn't help, there are more diagrams here.

http://www.vintagegolfcartparts.com/cgi-bin/gallery/gallery.cgi?Category=100013

 

Thanks for the quick responses! I may have to open it up to see what's going on inside. However I tested it with an ohmmeter today. Numbering the terminals 1-4 starting at top right in the photo, clockwise (#4 is on the left by itself), 1-4 shows about 10 ohm and 2-3 the same. All other combinations are open. So I’m guessing 1&4 are the armature and 2&3 are the field coils.
I connected 1&2 together and ran them to my battery's positive.
I connected 3&4 together and ran them to my battery's negative.
The motor turned very slowly and the battery got extremely hot. It may be undesized for the draw the motor requires.
I may try connecting the coils in serial, i.e. leave 1&2 together, but connect 3 to positive and 4 to negative.

 

I guess you know that golf carts are 36 volts.

 

You need to identify both the field and the armature, if you feed the armature without the field the motor will remain stationary, or practically slow and draw excessive current.
Max.

 

I figured it out. The motor is series-wound. Once I connected the stator and field coil in series it spun up beautifully (even at 12v, dna-robotics).
Thanks everyone!

 

If you run it in series mode you should only run it on load, it operates in a run-away condition off-loaded when in series.
Max.