Need help wiring drum switch.

Yes. I'm so used to none of the old motors usually found on these old lathes not having a thermal switch that I never thought of it.

And I agree. Very unusual to reverse the motor by reversing the run winding(s).
 
Mark, have a question on your drawing.
In the Reverse direction, doesn't that wiring scheme put an intermittent reversing polarity on the capacitor ???
I know you can do this on some capacitors, but not others.
Makes me wonder if the original wiring scheme (switching polarities of the Run windings) was due to the capacitor not being able to handle a reversing polarity.
 
Those types of capacitors are made to handle AC current, unlike electronics-type electrolytics they have no polarity.
Mark
 
just to be clear,
a capacitor can only store a DC charge.
a capacitor can have an AC input, but the capacitors output will always be DC
 
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That isn't exactly correct. I think what you meant is that any charge remaining on a capacitor (or condenser) will be DC. But capacitors will output AC if the input is AC, albeit with a phase shift.

But in the case of an AC motor start capacitor, to answer the previous comment, the capacitor is non-polarized. Plus in the case of a single phase AC motor start capacitor, it is fed with AC at the power line frequency and it does not matter which terminal goes where as far as the capacitor is concerned..
 
if a cap can't store a AC charge, how can it output one???
this is in reference to motor starting and motor running capacitors.
 
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Mike: it might help to think of a cap as a sphere with a rubber diaphram across the middle. Pulsations of air or water on one side
will give equal pulses on the other but no actual transfer of air or water will occur.
Caps are like a conductor for AC (depending on the value and frequency). This is true for all caps but motor caps are specially made to withstand AC.
The store and release action for DC takes time which is what gives the phase shift for AC.
Mark
ps Tesla was way ahead of his time!
 
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That isn't exactly correct. I think what you meant is that any charge remaining on a capacitor (or condenser) will be DC. But capacitors will output AC if the input is AC, albeit with a phase shift.
But in the case of an AC motor start capacitor, to answer the previous comment, the capacitor is non-polarized. Plus in the case of a single phase AC motor start capacitor, it is fed with AC at the power line frequency and it does not matter which terminal goes where as far as the capacitor is concerned..

My apologies, i stand corrected.
thanks for the clarification :grin:
 
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