Rewiring "reterminating"? 3 phase leads??? 1

[IntegrityTesting]

I also have a 220/440V 20 HP motor I think is permanently wired for 440... I pulled the back cover and the leads away from the windings and this is what I get...



OK... Pulled the back of the 20 HP apart...

All of these insulated leads are attached at the outer edge of the windings, clock orientation:

A=4&10
B=2&8
C=6&12

11&1&3 connected
5&7&9 connected

These insulated leads dive into the stator grooves and probably just connect phase coils?
10&1
11&2
12&3
4&7
5&8
6&9

ANY THOUGHTS?!?!?!?

Wired 440 v 220? And how can I put the standard 9 leads out of this motor??? I spent $220 on another motor, and don't want to pay to have this one done...

THANKS!

Attached Thumbnails Attached Thumbnails 20-hp-winding-leads-.jpg 20-hp-idler-plate-.jpg

 

[waross]

Are these existing numbers or your arbitrary numbers?
The connections may be for a consequent pole connection to cut the motor speed in half.
A standard wye low voltage connection would have #4, #5, and #6 connected and insulated and #10, #11, and #12 connected and insulated.
A nine lead motor will have #10, #11, and #12 connected internally and not accessible. THAT IS, IF THE NUMBERS FOLLOW STANDARD NUMBERING PRACTICE.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[IntegrityTesting]

Hi Bill...

Thanks for your help!

Yes... Those are my arbitrary tags specifically labeled by traditional clock orientation... There are only 12 lead take-offs from the rear of the windings, and only one per "clock position"... I'm not sure if this was supposed to be a 12 or 9 lead motor, but I see that there is some obscured high and low info on the plate... I'll get a better image...

All of the "clock position" numbers are connected internally on this motor as described above...

Is there any NEMA or other convention for orientation and position of lead take-offs from the windings?

Thanks again!

 

[waross]

It may be helpful to identify the poles. First, find each pair of leads with continuity. Next, apply DC to each pair in turn and use a battery to identify location and polarity of the poles.
One of our winding experts will give you more specific instructions.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Motorwinder]

2 wye connection. Could be 440 or 220. Normally, we'll mark the voltage on the nameplate when we rewind them to 3 leads.

If you want 9 leads, take it to a motor shop. They can determine if you need 1-2 wye, or 2-4 wye.

 

[waross]

Typo: I meant to say;
"Use a compass to identify the location and polarity of the poles."

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[petronila]

Hello Integrity

Your motor name plate is indicating the voltage is 220/440 but your connection is only for one voltage. So you most identify the right connection voltage.
in this case the best is test the motor with no load and note N.L.Current, test first with 220 Volts if N.L.current is between 12 to 20 Amperes then the motor is connected for 220 V. But if you found a N.L.Current between 3 to 4.8 the motor is connected for 440 V.

The connection that you found is two stars, but we don´t know the right design connection, Best way is N.L. Test.

If you need both voltages or the winding is connected for the wrong voltage the motor need to go to one shop for reconnection.


Regards


Carlos

 

[IntegrityTesting]

It may be helpful to identify the poles. First, find each pair of leads with continuity. Next, apply DC to each pair in turn and use a battery to identify location and polarity of the poles.
One of our winding experts will give you more specific instructions.
Typo: I meant to say;
"Use a compass to identify the location and polarity of the poles."

Bill,
So what you are saying (after I mark original connections) is to break the 2 wyes, and the 3 pairs on the 3 leads, and find the ends that have continuity? This would give me 12 individual leads coming off the coils, not including the coil pairing connections which I would assume are left intact… After I’ve marked these pairs, how do I determine “lead polarity”? with the compass? THANKS AGAIN BILL !

Motorwinder,
2 wye connection. Could be 440 or 220. Normally, we'll mark the voltage on the nameplate when we rewind them to 3 leads. I definitely have 2 sets of three leads connected centered about 180 degrees out… The other 3 pair are connected to the 3 leads A/B/C… The plate wasn’t marked that I can see…
If you want 9 leads, take it to a motor shop. They can determine if you need 1-2 wye, or 2-4 wye. I was trying to do this myself, as I had leads put on another motor FOR $220 that may be too big… THANKS FOR YOUR TIME!
Hello Integrity

Your motor name plate is indicating the voltage is 220/440 but your connection is only for one voltage. So you most identify the right connection voltage.
in this case the best is test the motor with no load and note N.L.Current, test first with 220 Volts if N.L.current is between 12 to 20 Amperes then the motor is connected for 220 V. But if you found a N.L.Current between 3 to 4.8 the motor is connected for 440 V. The no load idle current is what prompted me to suspect this was internally wired for 440V. Connected to SINGLE PHASE 220 (measured 245), and run up with a pony motor, my no load idle current was 6.6A/leg… Or 30% over, which would line up perfectly with 1 phase not helping…

The connection that you found is two stars, but we don´t know the right design connection, Best way is N.L. Test.

If you need both voltages or the winding is connected for the wrong voltage the motor need to go to one shop for reconnection. Definitely connected for the wrong voltage… I would like to change it to 220, myself… AND ideally wire the nine leads to the correct combination of 12 winding taps! THANKS FOR YOUR HELP CARLOS!

I guess the basic question here for everybody is:

1. How can I identify these 12 taps coming from the coils, and how do I connect 9 leads to 12 taps??? I am of course assuming that the other 12 connections “between coils” remain intact…

I want to thank everybody again… it really is great to have people that take the time to help others for no other reason than generosity of your knowledge….

Ed

PS my other related posts here:

http://www.eng-tips.com/viewthread.cfm?qid=360441

http://www.eng-tips.com/viewthread.cfm?qid=360297

 

[Motorwinder]

Drawn on paint hope it will help..

 

[IntegrityTesting]

THIS IS GREAT!!!!!!!!!!!!!!!!!!

EXACTLY what I was looking for.... I think (meaning if I understand this).... The lead connection I have down pat… You can speed quiz me later on wye/delta/hi/low terminal connections…..

So... If I have this right... I can pick ANY arbitrary reference point to start... Pick 3 “outside” taps skipping a pole between, and connect a wye… Pick the “opposite outside 3” and do the same thing… NOW…. My leads that would exit the motor to the peckerhead would be lead 1 connected to the two “1’s” (here outside 10&4 o’clock) … Lead 2 connected to both outside 2’s (12&6 o’clock-ish here)… Lead 3 to the outside taps at 2&8 o’clock… Lead 4 to the two INSIDE taps at 3:30&9:30 here…. And so on….

If I wanted to “hardwire this” to only have 3 leads come out… I would Wye each 4-5-6… Connecting L1/L2/L3 to “two 1’s”/two 2’s/two 3’s????

Man… I’m almost more excited than Christmas time….
(I hope I’m right….)

THANK YOU FOR YOUR HELP!!!!!!

:O)P***

 

[Motorwinder]

When you break the connections, make sure 1 has continuity with 4, 2 has continuity with 5 and so on.. In other words, 1 would be the start of the group of coils, 4 would be the finish.

If I wanted to “hardwire this” to only have 3 leads come out… I would Wye each 4-5-6… Connecting L1/L2/L3 to “two 1’s”/two 2’s/two 3’s????

No, follow the drawing..


This drawing is to bring out all 9 leads. The connections listed is for the external leads of the 9 lead motor on 220 volts.
the "two 1s" go to one lead marked #1. The "two 7s" go to one lead marked #7, and so on.

Out side on the 9 leads: 1 hooks to 7, 2 hooks to 8, 3 hooks to 9. 4-5-6 hooks together. This is for 220 volts!


Sure you don't want a winder to do it?
Good luck

 

[IntegrityTesting]

It must be amusing to see the light bulb go off on such a simple concept huh???
I mean, I can do some math that would make you pass out...
Build or fix something that would make you blink...

This was simple... I made it hard...

Thanks for all your help...

I got this man!

Ed

 

[IntegrityTesting]

Some Closure to this post...

I ended up rewiring the motor leads myself on the 20 HP motor, and everything works perfectly... There's something wrong with the 25 HP motor... It was simply pulling too many amps to just run a silly 10HP compressor...

NLA of the 25 was 35-37A with 250mfd caps on the generated leg, 47 without the caps, and the lowest load I could achieve running the compressor was 63A

NLA of the 20 was 7-10A with 250mfd caps on the generated leg, 23 without the caps, and the lowest load I could achieve running the compressor was 35A GOOD ENOUGH FOR ME!!!

I'd like to Thank everybody for their help, especially waross and motorwinder... I am now a rewiring fool... (a very dangerous thing!)

 

[LionelHutz]

So you just left it connected like it was when you first got it? The connections you describe were already done right for the low or 220V run connection assuming it is a Y-connection motor. Otherwise, you are using a 12-lead delta motor connected in double Y and it's now connected to operate at 380V.

 

[IntegrityTesting]

Nooooooo..... I broke connections for 4-7, 5-8, 6-9 on the interior windings, connected like numbers and led them all out.... It was wired high... This is not rocket science....

 

[LionelHutz]

That's odd because you described 12 leads for the motor connected as follows;

A=4&10
B=2&8
C=6&12

11&1&3 connected
5&7&9 connected

The coil or lead numbers are wrong but that is the connection configuration for a 12-lead motor for the low voltage Y configuration.

A = 1,7
B = 2,8
C = 3,9
4,5,6 and 10,11,12 get joined together. You can easily see that if you swap numbers around that what you listed and the accepted sequence are the same damn thing.

 

[IntegrityTesting]

Lionel,

The original numbers are arbitratry clock orientation....
IntegrityTesting (Mechanical)
All of these insulated leads are attached at the outer edge of the windings, clock orientation:
A=4&10
B=2&8
C=6&12
11&1&3 connected
5&7&9 connected

10&1
11&2
12&3
4&7
5&8
6&9


waross (Electrical)
22 Feb 14 16:13
Are these existing numbers or your arbitrary numbers?

IntegrityTesting (Mechanical)
22 Feb 14 16:54

Yes... Those are my arbitrary tags specifically labeled by traditional clock orientation... There are only 12 lead take-offs from the rear of the windings, and only one per "clock position"...

Here's what I changed...
OUTER WINDING TAPS
A=4&10 were relabeled 1&1, no change in connection
B=2&8 were relabeled 3&3, no change in connection
C=6&12 were relabeled 2&2, no change in connection
11&1&3 connected were relabeled 10, 11,12, no change in connection
5&7&9 connected were relabeled 10,11, 12 no change in connection
INNER WINDING TAPS
10&1 were broken and relabeled 6 & 9
11&2 were broken and relabeled 5 & 8
12&3 were broken and relabeled 4 & 7
4&7 were broken and relabeled 6 & 9
5&8 were broken and relabeled 5 & 8
6&9 were broken and relabeled 4 & 7

All like # pairs were connected internally, and 9 new leads were led to the peckerhead... As you can see...The motor was previously wired high....
1. It would not run a 230 10 HP compressor motor with a generated 3rd leg
2. I broke, relabeled internal connections and....
3. The will now run a 230 10 HP compressor motor with a generated 3rd leg
4. The loaded draw of the RPC motor is completely acceptable at 38A
5. Either I did this correctly, or I have some magic ability I'm not aware of...