Induction Motor Wiring Help Needed ...

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ok i have this motor it's a single phase 240v induction motor with capacitor start... it's on a small lathe

how do i wire it to get it to run ?

wire 1 & 2 (reds) give me a resistance on the multi-meter

wire 3 & 4 black (3) and yellow (4) give me a weird resistance from the cap i think. each time i reverse the multi-meter probes between 3&4
i assume it is the CAP doing something as the 3&4 wires go to the cap (and via the start run winding?)

there is no response between 2 & 3 or 2 & 4 or 1 & 3 or 1 & 4
and none of these are "earth"

(ignore the black red under the green drawings they are disabled and insulated )

from doing research it seems i need to join wires 1 & 3 as a pair then 2 & 4 as a pair and that should start the motor one way or the other
and to change direction i need to swap 3 & 4 over
but this was on a few wood working / metal type forums

would the start cap winding need to be "on" all the time or on some instantaneous switch ?

i have a real hard time in my mind joining the two reds to live and neutral..... and dont want it to let out the magic blue smoke

thanks for the help


Ducatiboy stu

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Your meter will give starnge readings when looking at the cap. Basically as you test for restistance the cap will charge up ( like a battery ) and when you swap the leads it will discharge, giving an indication of "+ pos" resistance.

You basically need to find the 2 terminals that will give resistance of the run winding. You cant measure the resistance of the start winding due to the cap

Hope this is as clear as mud ( or stout :D )

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