Idenifying leads of 12 lead Y start motor 1

[mosside]

I really hope someone can tell me how to identify the leads on this motor I have. All the information on lead identification has been for 9 lead motors and this is a 12 lead, dual voltage 230/460 Y start, delta run motor. Although this motor is designed be able to start on Y to limit inrush it can be started on delta and that is the way I will use it. Start and run on delta. Therefore I do not need to identify all the wires just which 3 sets of 4 wires that should be grouped together so it will start and run on delta, low voltage. I have found the six sets of two leads with continuity between them. What do I do now?

Thanks in advance, Doug

 

[davidbeach]

This has been discussed several times in this forum; a search should provide several threads to reference.

 

[mosside]

Sorry if this has been discussed. I spent a lot of time searching and only found dicussions of 6 and 9 lead motors and those that were wye connected. I'm out of search parameters to use! - Doug

 

[GS3]

This is not my specialty but I'll give you my thoughts while someone more knowledgeable comes along. I think you can conduct some low voltage tests which will give you some indications.

If what you have in these six windings is really three half windings for three poles then it should be fairly straightforward to detect how they are paired. Inject a low voltage in one winding and measure voltages in the others and the one with highest output voltage is the other half of the pair. This will also indicate polarity if you use a scope. If no one winding gives a higher voltage then you may have the following case.

If what you have are six independent windings for six independent poles, then what you really want to determine is the order and polarity. This seems to me quite a bit more complicated. I wonder if you can feed a low voltage to one winding and rotate the motor mechanically. That should induce voltages which you could analyze for phase and polarity on a scope.

Maybe someone who knows what the're talking about will be along with something more useful...

 

[GS3]

You might want to check thread237-153197 and specially the post by wiretwister dated 30 Apr 06 20:45 where he explains another method for determining polarity.

 

[nbucska]

I assume you have 110V one phase and 230V 3 phase.

First Identify the ends of all 6 coils -- mark the two ends
of each of the 6 coils with one letter A,B,C,D,E,F.

Next connect a 110V 100W light bulb is series with
two clips and the 110V AC. Connect the clips to the ends
of "A". Mark the ywo ends with 1 and 2.

Find among the remaining coills the one with the
highest AC voltage. Call this value VX: Connect
one end of this to point "2". Measure the AC
between "1" and the free end of the second coil.
If the AC voltage is <<1/2 VX, switch the ends of the second coil.

When the VTG is > 3/2 Vx, mark the connected end of the
second coil with "3", the free end with "4" .
So you identified X1,X2,X3,and X4.

Call the ends of one remaining coil "Y1 " and "Y2"
Find coil with highest V.
Find its polarity which gives >>3/2 Vx
Mark the connected end "Y3", the free end "Y4"
----------------------------------------------------
Leave the three serial connection in place i.e.
leave the motor connected to 460V.
To recapitulate in each phase (X,Y,Z) 1 and 4 are the
inputs, 2 and 3 are sorted.

(To connect to 230V, in each phase the shorted 1 and 3
is one input the shorted 2 and 4 is the other one.)
Repeat this with coils "Z"

Now connect the end "4" of each phase together
and connect the ends "X1","Y1" and "Z1" to the
230 3 phase. The motor should run without
too much hum and the current in the three phases
should be about the same. If one is very differnt
interchange end "1" and "4" of this phase and if
the retest is OK, renumber 1-2-3-4 of this phase
to 4-3-2-1.
Now you may connect it to 230V Y or delta, if you wish.
--------------------------------------------------
If You have single VTG Y/Delta motor, (6 lines)
you may use lower voltage for the run-test or
use serial resistors in the three phases.




----------------------------
Please read FAQ240-1032
My WEB: <

http://geocities.com/nbucska/>

 

[mosside]

Thanks so much everyone. I should be good to go!

Doug