I came home from vacation to blazing heat in my upstairs. I could hear
A binding sound in a/c duct and no air flow out of the vents. I looked
At my a/c controls on the wall and the light was on, indicating the
Unit was operating. I checked the outside a/c unit and the fan was on.
My controls were set to auto. I changed them to fan setting and I
Could hear the binding sound. I went to the attic and could smell a
Burning wire type odor. I thought it was the fan motor in the duct. I
Removed the motor and cage and the same noise is still there right beyond
The cage assembly. I do not know what could be binding and causing the
Odor. I cannot get any air flow.

Any assistance would be appreciated

Check the main blower motor in the unit in the attic. It usually is the only motor in the unit that can cause what you are describing. Also check the furnace filter while you are at it.