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#### Woodsmith

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4,841 Posts
Here is something to think about for given motor:
Volts equates to RPM
and
Amps equates to Torque.

Volts X Amps equals Watts
Torque X RPM/5252 equals Horse Power
Just out of interest, what units are you using for torque in the last line, GT?

#### Woodsmith

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4,841 Posts
You need to use Feet-lbs!

240 ft-lbs x 2500 rpm / 5252 = 114 hp
Thanks Yabert.
I did a very quick mental calc while in classes today (ok shouldn't have been on here while studying ) and the numbers, using ft-lbs seemed bigger then I expected. That's a good thing, right?

#### Woodsmith

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4,841 Posts
I have been reviewing this post and previous ones I have posted,and need some help understanding. I understand what the commutator is and it's segments, but the windings confuse me.
Which bit confuses you?

The armature has comm segments that are connected to copper windings that are on the core of the armature. If you take out an armature you can trace the route of the thick copper conductors on it.
As the armaure rotates the brushes contact certain segments of the comm causing a magnetic field to form in the energised coils.

The frame of the motor houses, typically, four big coils of copper conductors. These are the field windings. They are energised constantly when the motor is running and provide a magnetic field that is fixed in location to the frame.

The magnetic field in the armature is attempting to align with the field windings but because they are not physically aligned the force generated 'pulls' the armature around. However, as the armature is pulled around to align with the field windings the brushes then begin to break contact with that armature winding and moves to make a connection to the next one. And so the process begins again and the armature is pulled around further.

In a series motor the copper conductors used in the armature and the field windings are very big and have few turns. This allows the same amount of current to be carried by both the fields and the armature windings.

With a shunt motor the field coils are made up of many more turns of much thinner conductors as they don't have to carry the current that passes through the armature. They are wired in parallel to the armature.

Anything more complex will need to be answered by those more knowledgable then me (they will probably correct any errors in my post too).

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