Troubleshooting an Enco lathe motor

I don't think you can do a definitive test with both wires attached to the capacitor, at any rate, this test, while advisory that the cap might be OK, it does not test for capacitance, for that, a capacitor analyzer is necessary.
 
benmychree said:
I don't think you can do a definitive test with both wires attached to the capacitor, at any rate, this test, while advisory that the cap might be OK, it does not test for capacitance, for that, a capacitor analyzer is necessary.
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Thank you for your input, I appreciate it.

I will check back in tomorrow, Goodnight, Thank you guys!
 
OK I'm back- one thing I should mention is your Fluke 73 meter has a manual range mode which would be advantageous to use when
measuring low ohm things like motor windings. You use the pushbutton in the center of the selector switch.
The lowest ohm range I believe is 200 ohm full scale (199.9)
So when doing the test from post #3 you should see something less than a dozen ohms (cap shorted, measure from straps to red ZR terminal):
Encomotterm1a.jpeg
 

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You should also get a low ohm reading from the main windings (brown and blue terminals)


The cap looks to be pretty old, most folks here would say replace it if it's OEM and several years old
 
Good morning Mark,

I am assuming "Cap shorted" Means I still have the jumper clipped to the terminals on it?

OK so when I push the center button on my meter it displays a "M" on the right side of the screen. Using it in this mode when testing between the L-straps and the terminal for the red wire its does nothing and still displays .0L, When testing between the other 2 terminals it flashes to .000 on both of the other terminals.

Edit: Just to be sure I changed the battery out and redid the tests. I still get .0L on the red terminal and I get .008 on blue and .009 on brown.
 
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Yes cap shorted means with jumper wire clipped on
You have to push the meter range button several times to cycle through the ranges, I think.
You should see the decimal point move.
In post #15 the meter needs to be connected to blue and brown terminals (U and V) on the motor. That checks the main windings

When you connect the meter to the straps and the red terminal (I call ZR) you should be getting a low ohm reading, less than 10
If it's reading "OL" that means open circuit- that could be the problem

Check your meter by shorting the test leads together- you should get 0 or very close whichever ohm range you are on
When the leads are apart you get something like OL or open leads
 
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It's looking like you'll need to open up the motor I think. If the cap is shorted with a jumper, and you are not getting continuity from the straps to the ZR terminal then the start leg is open
That means either the start winding is open or the internal centrifugal switch is stuck or broken. That switch is normally closed and opens when the motor runs to disconnect the start circuit so it won't overheat
 
Ok Thanks Mark,

When I press the button it moves the decimal point over. After doing so, I measure 1.6 across blue and brown terminals (U and V) on the motor

I get no continuity on ZR
 
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