Question { 3094 }

can motors working at parallel operation like D.G set and
transformers? It means asking about two motors coupled with
same load???

Answer

Yes., Motor can work in Tandem for the same load. Some
times when the load is too much we can use two motors with
geared coupling ( Direct) or indirectly coupled through
wire or felt or sprocket and we have to use load sharing
technology ( Available in Electronic drives )

Question { 10125 }

In a 3Ph induction motor(old) 6 wires came out from terminal
& not mentioned u1,v1,w1,u2,v2 & w2. how can find out the
terminals? how can connect to star delta starter??

Answer

first of all you have to use multimeter to identify the
coil teminals. segregate it in two lines as 2 x 3 . ie top
3 terminals and bottom 3 terminals.

Next take a Small DC power supply with 3 volt and a
milliampere meter( DC ). connect this voltage to one of the
coils with milliampere meter in series( Milliampere meter
should be of center zero type ) close the supply voltage to
the coil with make and break it immediately. observe the
deflection whether it is on forward side or reverse side.
and mark one terminal for whcih +ve suplly is connected as
Start and the other ( _ ve )end as Finish. do this
process for other two coils also. once you know the top 3
start points and finish points of the coil. you are almost
there. now you short ckt all finish ends. you are left
with 3 start terminals. ie your STAR connection.

For Delta connection connect finish end of the first coil
to start end of the second coil, finish end of second coil
to start end of third coil and finish end of 3third coil
to start end of first coil. now you have theree junctions.
now your connection is in Delta mode.