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18 Terminal motor winding connection
4

18 Terminal motor winding connection

18 Terminal motor winding connection

(OP)
I am trying to connect an older 11HP EMB brand motor with 18 terminals at the motor windings. The motor was apparently used in a high voltage (440V) application with an elaborate control system with 12 contact in the motor leads. I am told the motor is two speed and dual voltage. The customer wishes to control the motor using two starters separately switched to engage high and low speed through a selector switch and timer. I have the controls worked out but need to know how the terminals on the motor must be connected to the two starters for 220V three phase power if it is possible.

RE: 18 Terminal motor winding connection

(OP)
The motor is a european model made by EMB. Type DK11, Motor #816243. It has  y/yy 440/220v 12/24A  1740 RPM 9.0 PS and Y/YY 440/220V 26/25A 3480RPM 18.0 PS. The terminals are marked (In no particular order of position)U1 V1 W1 X1 Y1 Z1 U2 V2 W2 X2 Y2 Z2 U11 V11 W11 U22 V22 W22. Originally there were jumper bars across U11-X1 V11-Y1 W11-Z1 U22-X2 V22-Y2 and W22-Z2 when it was connected to high voltage.

RE: 18 Terminal motor winding connection


Sounds like it is a 60Hz dual-voltage motor, so there are probably three or six coil pairs that are connected in series for the higher voltage and in parallel for the lower voltage.  An ohmmeter may help determine if the coils are tapped.  

There are several varieties of switching for multi-speed motors.  Chances are the correct starter has at least two contactors that are mechanically and electrically interlocked.  Contactor currents double at half voltage.

U-V-W / X-Y-Z are {IEC} coil-end conventions in the simplest of single-speed, wye-start/delta-run motors.  
  

RE: 18 Terminal motor winding connection


Take note ... at high voltage the unused winding is open circuit due to the SINGLE star connection.

In order to avoid circulating currents at low voltage through the unused winding you cannot just leave them TWO STAR at the motor ... the two star PARALLEL connection must be split!

This wont be possible with just two starters!

RE: 18 Terminal motor winding connection

Four starters will be needed for the two speed / two winding motor, low voltage connection.

Two starters will be needed for each speed to energize the star pairs together.

This then keeps the other speeds STAR connections from being parallel connections when it is not energized.

RE: 18 Terminal motor winding connection

Comment on busbar (Electrical) Mar 21, 2004 marked ///\\\
Sounds like it is a 60Hz dual-voltage motor, so there are probably three or six coil pairs that are connected in series for the higher voltage and in parallel for the lower voltage.
///Six coil pairs would give 12 coil terminals only, since 6x2=12. There would have to be nine coil pairs to obtain 9x2=18 since the original posting states:
"""... motor with 18 terminals at the motor windings..."""\\\
  An ohmmeter may help determine if the coils are tapped.  
///This is more like it.\\\

RE: 18 Terminal motor winding connection

2
The nameplate data shows:
Speeds 1740 rpm and 3480 rpm, then the motor is 4 and 2 poles, 60 HZ.
Y/YY for 440/220 Volts in both speeds.
It has 18 terminals for Two Speed- Two Windings.
Each winding is independent and with standard nine leads.
The original jumper bars were for series wye or 440 volts.
New connection for 220 Volts is:

FIRST SPEED ( I assume is 4 Poles because it is the first printed in the plate)

L1 to U1and U11
L2 to V1and V11
L3 to W1and W11

X1-Y1-Z1 together (neutral)

SECOND SPEED ( I assume is 2 Poles )

L1 to U2and U22
L2 to V2and V22
L3 to W2and W22

X2-Y2-Z2 together (neutral)

Check with multimeter that motor leads continuity should ring only:
U1&X1, V1&Y1, W1&Z1 and  U11toV11toW11
U2&X2, V2&Y2, W2&Z2 and  U22toV22toW22

RE: 18 Terminal motor winding connection

aolalde is right on target.
However I would suggest that a motor rotation analyzer be used to account for the coil polarity.

RE: 18 Terminal motor winding connection



Using Aolalde's good work, my connections would be like this...

First speed, contactor A and contactor B simultaneously energizing...

L1A to U1
L2A to V1
L3A to W1

L1B to  U11
L2B to  V11
L3B to  W11

X1-Y1-Z1 together (neutral)


SECOND SPEED ( I assume is 2 Poles )

Contactors C and D simultaneously energizing...

L1C to U2
L2C to V2
L3C to W2

L1D to  U22
L2D to  V22
L3D to  W22


X2-Y2-Z2 together (neutral)
    
    
Make sure to tell us if Aolalde's description of leaving the stars in parallel works or if you do end up having to separate the unused winding as I have suggested!    
    
    

RE: 18 Terminal motor winding connection

Suggestion: Visit
http://www.sea.siemens.com/contrlbu/upld/files/p41-46.pdf
for Figure 10 where 2 speed 3 phase 2 winding motor has only 12 terminals (there are 12 coil ends). If the dual voltage is considered, additional three winding (or winding extensions, depending on the winding or coil definition) will be required, i.e. additional 6 coil ends totaling 18 coil ends.

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