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Modern electric motors adhere to the leads being colored to identify them,
WHITE = Common
BLACK = High speed
BLUE = Medium speed
RED = Low speed
BROWN = Run capacitor
BROWN/WHITE STRIPE = Run Capacitor
However sometimes we run across motors with strange colors or all black etc that precludes this,in this cases you
can ohm the leads to each other to determine which lead is what. Grab any lead and ohm it to the remaining leads
and note.
Take the lead that reads the highest and ohm it to all remaining leads and note just as you did the 1st time.
The 2 leads with the highest reading between them are Run and Start, this is because we are reading both windings
in series.
Common is the point the Run and Start windings are connected to each other, the Start winding is longest and has
more resistance to Common than the Run winding does.
The speed leads are from the Run winding with the Low speed reading higher to Common than Medium and Medium reading
higher to Common than High speed.
If you ohm the Run winding and then ohm the start winding, the 2 values should add up to the reading between Run and
Start
and as mentioned the speeds are on Run with the high speed being the lowest resistance to Common and Low speed
reading higher.
Example,
The Run winding = 3 ohms to Common
The Start winding = 5 ohms to Common
So Between Run & Start should = 8 ohms
Any remaining leads are speeds they will read something like this usnig the example of the Run winding being 3 ohms,
The Low speed may read 2.3 ohms and medium 2.0 and High 1.7 ohms to Common.
The speeds are on the Run winding which is 3 ohms so they must be less than that reading, they will be staggered in
this way with the low speed reading higher than medium and medium reading higher than High and High speed reading
the lowest to Common.
I have diagrams however I cannot post them I will try the photo section to post them for now.
WHITE = Common
BLACK = High speed
BLUE = Medium speed
RED = Low speed
BROWN = Run capacitor
BROWN/WHITE STRIPE = Run Capacitor
However sometimes we run across motors with strange colors or all black etc that precludes this,in this cases you
can ohm the leads to each other to determine which lead is what. Grab any lead and ohm it to the remaining leads
and note.
Take the lead that reads the highest and ohm it to all remaining leads and note just as you did the 1st time.
The 2 leads with the highest reading between them are Run and Start, this is because we are reading both windings
in series.
Common is the point the Run and Start windings are connected to each other, the Start winding is longest and has
more resistance to Common than the Run winding does.
The speed leads are from the Run winding with the Low speed reading higher to Common than Medium and Medium reading
higher to Common than High speed.
If you ohm the Run winding and then ohm the start winding, the 2 values should add up to the reading between Run and
Start
and as mentioned the speeds are on Run with the high speed being the lowest resistance to Common and Low speed
reading higher.
Example,
The Run winding = 3 ohms to Common
The Start winding = 5 ohms to Common
So Between Run & Start should = 8 ohms
Any remaining leads are speeds they will read something like this usnig the example of the Run winding being 3 ohms,
The Low speed may read 2.3 ohms and medium 2.0 and High 1.7 ohms to Common.
The speeds are on the Run winding which is 3 ohms so they must be less than that reading, they will be staggered in
this way with the low speed reading higher than medium and medium reading higher than High and High speed reading
the lowest to Common.
I have diagrams however I cannot post them I will try the photo section to post them for now.
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