I read a lot of write ups on using capacitors to balance the 3PH out of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B & C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on the
transformer, but try as I might. I just can't get 3 legs of 440. I can get
two, but as soon as I try to dial in the wild leg, (using the taps) one of
the other legs goes high or low.

Any help appreciated

--
Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

On 2009-02-25, Milo milo@oil wrote:
I read a lot of write ups on using capacitors to balance the 3PH out of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B & C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on the
transformer, but try as I might. I just can't get 3 legs of 440. I can get
two, but as soon as I try to dial in the wild leg, (using the taps) one of
the other legs goes high or low.

How does voltage look on the 230v side?

i

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"Ignoramus31514" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
I read a lot of write ups on using capacitors to balance the 3PH out of
a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V
lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler
motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B &
C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on the
transformer, but try as I might. I just can't get 3 legs of 440. I can
get
two, but as soon as I try to dial in the wild leg, (using the taps) one
of
the other legs goes high or low.

How does voltage look on the 230v side?

All 3 legs are +/- 230V

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

"Proctologically Violated©®" wrote in message
...
Milo" milo@oil filter.hughes.net wrote in message
...
"Ignoramus31514" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
I read a lot of write ups on using capacitors to balance the 3PH out
of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V
lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler
motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B
& C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on
the
transformer, but try as I might. I just can't get 3 legs of 440. I can
get
two, but as soon as I try to dial in the wild leg, (using the taps) one
of
the other legs goes high or low.

How does voltage look on the 230v side?

All 3 legs are +/- 230V

So you're saying you have the rpc balanced with caps, before you add the
transformers?

What values have you used?

Also, I don't know that you need a pony motor, as I think you need caps
from A to B *and* from B to C.
To start the idler, just disconnect the B to C caps, start the idler with
A to B caps, and then switch in B to C caps.

But, either way, if you have the rpc balanced before adding the
transformer, mebbe just experiment with add'l caps after adding the
transformer -- with the same taps for all three phases.

--

Mr. PV'd

Mae West (yer fav Congressman) to the Gangster (yer fav Lobbyist):
Hey, Big Boy, is that a wad (of cash) in yer pocket, or are you just
glad to see me??

There are no caps in the system at this time.

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

On 2009-02-25, Milo milo@oil wrote:
"Proctologically Violated??" wrote in message
...
Milo" milo@oil filter.hughes.net wrote in message
...
"Ignoramus31514" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
I read a lot of write ups on using capacitors to balance the 3PH out
of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V
lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler
motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B
& C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on
the
transformer, but try as I might. I just can't get 3 legs of 440. I can
get
two, but as soon as I try to dial in the wild leg, (using the taps) one
of
the other legs goes high or low.

How does voltage look on the 230v side?

All 3 legs are +/- 230V

So you're saying you have the rpc balanced with caps, before you add the
transformers?

What values have you used?

Also, I don't know that you need a pony motor, as I think you need caps
from A to B *and* from B to C.
To start the idler, just disconnect the B to C caps, start the idler with
A to B caps, and then switch in B to C caps.

But, either way, if you have the rpc balanced before adding the
transformer, mebbe just experiment with add'l caps after adding the
transformer -- with the same taps for all three phases.

--

Mr. PV'd

Mae West (yer fav Congressman) to the Gangster (yer fav Lobbyist):
Hey, Big Boy, is that a wad (of cash) in yer pocket, or are you just
glad to see me??

There are no caps in the system at this time.

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/



Add two caps, one on legs 1-3 and one on 2-3, start with 140 uF.
--
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to spammers, I and many others block all articles originating
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"Ignoramus23604" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
"Proctologically Violated??" wrote in message
...
Milo" milo@oil filter.hughes.net wrote in message
...
"Ignoramus31514" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
I read a lot of write ups on using capacitors to balance the 3PH out
of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V
lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler
motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A
B
& C
feed into a 440/208 auto transformer 'backwards' to boost the
voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on
the
transformer, but try as I might. I just can't get 3 legs of 440. I
can
get
two, but as soon as I try to dial in the wild leg, (using the taps)
one
of
the other legs goes high or low.

How does voltage look on the 230v side?

All 3 legs are +/- 230V

So you're saying you have the rpc balanced with caps, before you add the
transformers?

What values have you used?

Also, I don't know that you need a pony motor, as I think you need caps
from A to B *and* from B to C.
To start the idler, just disconnect the B to C caps, start the idler
with
A to B caps, and then switch in B to C caps.

But, either way, if you have the rpc balanced before adding the
transformer, mebbe just experiment with add'l caps after adding the
transformer -- with the same taps for all three phases.

--

Mr. PV'd

Mae West (yer fav Congressman) to the Gangster (yer fav Lobbyist):
Hey, Big Boy, is that a wad (of cash) in yer pocket, or are you just
glad to see me??

There are no caps in the system at this time.

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/



Add two caps, one on legs 1-3 and one on 2-3, start with 140 uF.

Add them after the transformer?

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

On 2009-02-25, Milo milo@oil wrote:

before or after the transformer?

Add them onto the motor, before transformer.

My phase converter has this configuration, capacitors on each leg, and
it works well, both under load as well as without. I redid my math,
and in proportion to your idler's HP, you would need 80 uF, if you
were to use the same uF per HP as I do.

i

"Ignoramus23604" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:

before or after the transformer?

Add them onto the motor, before transformer.

My phase converter has this configuration, capacitors on each leg, and
it works well, both under load as well as without. I redid my math,
and in proportion to your idler's HP, you would need 80 uF, if you
were to use the same uF per HP as I do.

i

Thanks for your help, I start looking for caps.

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

In article ,
"Milo" milo@oil filter.hughes.net wrote:

I read a lot of write ups on using capacitors to balance the 3PH out of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B & C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on the
transformer, but try as I might. I just can't get 3 legs of 440. I can get
two, but as soon as I try to dial in the wild leg, (using the taps) one of
the other legs goes high or low.

If I understand the description, the autotransformer is three phase. If
so, one can the treat autotransformer and motor as a unit, and apply the
balancing capacitors to the idler motor as if it were connected to a 220
volt 3 phase motor. Varying the taps on the autotransformer doesn't
sound right.

A wiring diagram would be useful.

Joe Gwinn

OK, here are the results of connecting 104uF caps between legs A-B & B-C on
the output of the idler motor.

At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.


--
Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/
"Milo" milo@oil filter.hughes.net wrote in message
...
"RoyJ" wrote in message
...
Heh!! an unconventional way of drawing it but perfectly clear.

With the pony motor you don't need to worry about starting. Just put a
run cap from each 220 leg to the wild leg. Iggy had some values for the
caps, good place to start.

Here's a good place to start for the necessary caps.
http://www.surpluscenter.com/sort.asp?keyword=EMRC

Thanks for the help. I'll post back here as soon as get some caps.

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/








Milo wrote:
"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

I read a lot of write ups on using capacitors to balance the 3PH out
of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V
lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler
motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B
& C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on
the
transformer, but try as I might. I just can't get 3 legs of 440. I can
get
two, but as soon as I try to dial in the wild leg, (using the taps)
one of
the other legs goes high or low.
If I understand the description, the autotransformer is three phase.
If
so, one can the treat autotransformer and motor as a unit, and apply
the
balancing capacitors to the idler motor as if it were connected to a
220
volt 3 phase motor. Varying the taps on the autotransformer doesn't
sound right.

A wiring diagram would be useful.

Joe Gwinn

This is not professional, but should be helpful.
I don't know if pics are allowed here. So here is a link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

On 2009-02-25, Milo milo@oil wrote:
OK, here are the results of connecting 104uF caps between legs A-B & B-C on
the output of the idler motor.

Should be A-C and B-C, assuming A and B are "line in" and C is the
generated leg.

Could you clarify.

i

At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.



--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
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"Ignoramus23604" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
OK, here are the results of connecting 104uF caps between legs A-B & B-C
on
the output of the idler motor.

Should be A-C and B-C, assuming A and B are "line in" and C is the
generated leg.

Could you clarify.

Sorry my typo. The caps are hooked A-C & B-C

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/



i

At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.



--
Due to extreme spam originating from Google Groups, and their
inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

On 2009-02-25, Ignoramus23604 wrote:
On 2009-02-25, Milo milo@oil wrote:
OK, here are the results of connecting 104uF caps between legs A-B & B-C on
the output of the idler motor.

Should be A-C and B-C, assuming A and B are "line in" and C is the
generated leg.

Could you clarify.

The voltages that you posted, are suggestive that you were correct in
stating how you connected the caps (improperly). Try to connect them
properly and see if voltages normalize.

Try without the transformer connected, first.

i


i

At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.




--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

"Proctologically Violated©®" writes:

Here's a good place to start for the necessary caps.
http://www.surpluscenter.com/sort.asp?keyword=EMRC

Not a bad site, but not super bargains.

Graingers actually has better prices and a better selection, in their
"closeouts" -- which appear at the end of a selected category, which could
be after quite a few pages.

Ask http://www.electronicsurplus.com/ and or meci.com; both noted
surplus outlets.
--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

"Ignoramus23604" wrote in message
...
On 2009-02-25, Ignoramus23604 wrote:
On 2009-02-25, Milo milo@oil wrote:
OK, here are the results of connecting 104uF caps between legs A-B &
B-C on
the output of the idler motor.

Should be A-C and B-C, assuming A and B are "line in" and C is the
generated leg.

Could you clarify.

The voltages that you posted, are suggestive that you were correct in
stating how you connected the caps (improperly). Try to connect them
properly and see if voltages normalize.

Try without the transformer connected, first.

Ok here are the connections and readings before the transformer:

Idler motor 9 leads, leg 1 = 3&9, leg 2 = 2&8, leg 3 = 1&7
leads 4*5*6 joined.

Now the caps (they were wired correctly, however I should add that the caps
consist of 4- 26uF caps in parallel). So leg1 to cap,(and wire to
transformer) cap to leg 2. leg 3 to other cap,(and wire to transformer) cap
to leg 2. Sorry I can't explain in proper terms.
I will add to my drawing and post a link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg

Now the voltage reading with idler running, not hooked to transformer:

Leg 1 = 256V

Leg 2 = 241V

Leg 3 = 268V

Peace
Milo







At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.




--
Due to extreme spam originating from Google Groups, and their
inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

On 2009-02-25, Milo milo@oil wrote:
"Ignoramus23604" wrote in message
...
On 2009-02-25, Ignoramus23604 wrote:
On 2009-02-25, Milo milo@oil wrote:
OK, here are the results of connecting 104uF caps between legs A-B &
B-C on
the output of the idler motor.

Should be A-C and B-C, assuming A and B are "line in" and C is the
generated leg.

Could you clarify.

The voltages that you posted, are suggestive that you were correct in
stating how you connected the caps (improperly). Try to connect them
properly and see if voltages normalize.

Try without the transformer connected, first.

Ok here are the connections and readings before the transformer:

Idler motor 9 leads, leg 1 = 3&9, leg 2 = 2&8, leg 3 = 1&7
leads 4*5*6 joined.

Now the caps (they were wired correctly, however I should add that the caps
consist of 4- 26uF caps in parallel). So leg1 to cap,(and wire to
transformer) cap to leg 2. leg 3 to other cap,(and wire to transformer) cap
to leg 2. Sorry I can't explain in proper terms.

So, which leg is generated? L2?

i

I will add to my drawing and post a link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg

Now the voltage reading with idler running, not hooked to transformer:

Leg 1 = 256V

Leg 2 = 241V

Leg 3 = 268V

So you measured voltage on 1-2, 2-3, 1-3?

i

Peace
Milo







At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.







--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

"Ignoramus23604" wrote in message
...
On 2009-02-25, Milo milo@oil wrote:
"Ignoramus23604" wrote in message
...
On 2009-02-25, Ignoramus23604
wrote:
On 2009-02-25, Milo milo@oil wrote:
OK, here are the results of connecting 104uF caps between legs A-B &
B-C on
the output of the idler motor.

Should be A-C and B-C, assuming A and B are "line in" and C is the
generated leg.

Could you clarify.

The voltages that you posted, are suggestive that you were correct in
stating how you connected the caps (improperly). Try to connect them
properly and see if voltages normalize.

Try without the transformer connected, first.

Ok here are the connections and readings before the transformer:

Idler motor 9 leads, leg 1 = 3&9, leg 2 = 2&8, leg 3 = 1&7
leads 4*5*6 joined.

Now the caps (they were wired correctly, however I should add that the
caps
consist of 4- 26uF caps in parallel). So leg1 to cap,(and wire to
transformer) cap to leg 2. leg 3 to other cap,(and wire to transformer)
cap
to leg 2. Sorry I can't explain in proper terms.

So, which leg is generated? L2?

L2 is the "ghost" or "wild" leg, as I have heard it referred to.
I carried that leg consistantly throughout the wiring
(idler-transformer-lathe).
ie: it is always the middle leg, wether leaving the idler, or going to the
lathe, from the transformer.

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/









i

I will add to my drawing and post a link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg

Now the voltage reading with idler running, not hooked to transformer:

Leg 1 = 256V

Leg 2 = 241V

Leg 3 = 268V

So you measured voltage on 1-2, 2-3, 1-3?

i

Peace
Milo







At the motor A-C = 238V
A-B = 255V
B-C = 218V
(B is the 'wild" leg

At the transformer output H-1-H-2 = 493V
H-1-H-3 = 501V
H-2-H-3 = 517V
The taps on the transformer are set as low as they go.







--
Due to extreme spam originating from Google Groups, and their
inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

[snip]

If I understand the description, the autotransformer is three phase.
If
so, one can the treat autotransformer and motor as a unit, and apply
the
balancing capacitors to the idler motor as if it were connected to a
220
volt 3 phase motor. Varying the taps on the autotransformer doesn't
sound right.

A wiring diagram would be useful.

Joe Gwinn

This is not professional, but should be helpful.
I don't know if pics are allowed here.

Pictures are not allowed.


So here is a link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg

It is clear.

The autotransformer is three phase, as suspected. Changing taps on this
autotransformer will have an effect to be sure, but not an obvious one.

Joe Gwinn


Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/


I have updated my drawing to show the caps installed.
http://s235.photobucket.com/albums/ee67/mholroyd/?action=view&current=RPC.jpgI'm
at a loss as to how to even out the voltage. More caps? Chuck the
transformer, and rewire the 440V lathe motor to 220?

Just to recap (no pun intended) Volt readings from idler (without being
connected to transformer) A-C =238V, A-B=255V, C-B=218V

Readings from transformer output, with idler hooked to the transformer
input.

H-1-H2=493V, H1-H3=501, H2-H3=517

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

Sorry, screwed up the link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg



Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

In article ,
"Milo" milo@oil filter.hughes.net wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

[snip]

If I understand the description, the autotransformer is three phase.
If
so, one can the treat autotransformer and motor as a unit, and apply
the
balancing capacitors to the idler motor as if it were connected to a
220
volt 3 phase motor. Varying the taps on the autotransformer doesn't
sound right.

A wiring diagram would be useful.

Joe Gwinn

This is not professional, but should be helpful.
I don't know if pics are allowed here.

Pictures are not allowed.


So here is a link.
http://s235.photobucket.com/albums/e...&current=RPC.j
pg

It is clear.

The autotransformer is three phase, as suspected. Changing taps on this
autotransformer will have an effect to be sure, but not an obvious one.

Joe Gwinn


Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/


I have updated my drawing to show the caps installed.
http://s235.photobucket.com/albums/e...rrent=RPC.jpgI
'm
at a loss as to how to even out the voltage. More caps? Chuck the
transformer, and rewire the 440V lathe motor to 220?

Just to recap (no pun intended) Volt readings from idler (without being
connected to transformer) A-C =238V, A-B=255V, C-B=218V

Readings from transformer output, with idler hooked to the transformer
input.

H-1-H2=493V, H1-H3=501, H2-H3=517

Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

There was a long thread on how to balance the phases. Do this on the
220 volt side of the autotransformer, as if autotransformer and motor
were one unit. At least in theory this should do it.

Joe Gwinn

What is the autotransformer going to do ?

And is it linear like most or log based for lighting controls ?

A transformer isn't used to change the speed of an ac motor.

Martin

Joseph Gwinn wrote:
In article ,
"Milo" milo@oil filter.hughes.net wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

[snip]
If I understand the description, the autotransformer is three phase. If
so, one can the treat autotransformer and motor as a unit, and apply the
balancing capacitors to the idler motor as if it were connected to a 220
volt 3 phase motor. Varying the taps on the autotransformer doesn't
sound right.

A wiring diagram would be useful.

Joe Gwinn
This is not professional, but should be helpful.
I don't know if pics are allowed here.

Pictures are not allowed.


So here is a link.
http://s235.photobucket.com/albums/e...urrent=RPC.jpg

It is clear.

The autotransformer is three phase, as suspected. Changing taps on this
autotransformer will have an effect to be sure, but not an obvious one.

Joe Gwinn


Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

In article ,
"Martin H. Eastburn" wrote:

What is the autotransformer going to do ?

It's used backwards, to step 220 up to the 440 needed by the
machine-tool motor.


And is it linear like most or log based for lighting controls ?

Linear, made of copper and iron, intended for 3 phase. From what Milo
has said, it's a tapped transformer.


A transformer isn't used to change the speed of an ac motor.

True. This is a phase-conversion setup, not a VFD.

Milo published his schematic.

Joe Gwinn


Martin

Joseph Gwinn wrote:
In article ,
"Milo" milo@oil filter.hughes.net wrote:

"Joseph Gwinn" wrote in message
...
In article ,
"Milo" milo@oil filter.hughes.net wrote:

[snip]
If I understand the description, the autotransformer is three phase. If
so, one can the treat autotransformer and motor as a unit, and apply the
balancing capacitors to the idler motor as if it were connected to a 220
volt 3 phase motor. Varying the taps on the autotransformer doesn't
sound right.

A wiring diagram would be useful.

Joe Gwinn
This is not professional, but should be helpful.
I don't know if pics are allowed here.

Pictures are not allowed.


So here is a link.
http://s235.photobucket.com/albums/e...&current=RPC.j
pg

It is clear.

The autotransformer is three phase, as suspected. Changing taps on this
autotransformer will have an effect to be sure, but not an obvious one.

Joe Gwinn


Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/

milo,
i sent you an email from catalina0029.
if you don't get it, re here and I'll send it again

On Tue, 24 Feb 2009 20:53:44 -0500, "Milo" milo@oil
filter.hughes.net wrote:

I read a lot of write ups on using capacitors to balance the 3PH out of a
idler motor.
But, I can't find anything on using them with a 440V system.

Brief description of my set-up: (what I'm trying to run is a 5HP 440V lathe
motor 2 speed, reversible)

I have a 110V 1PH 1.5HP pony motor, belted to a 230V 3PH 7.5HP idler motor.
Feeding the idler motor with 220V 1PH on A & C leg, wild leg on B. A B & C
feed into a 440/208 auto transformer 'backwards' to boost the voltage.

I'm having a hell-uv-a time dialing in my 440V. I have multi taps on the
transformer, but try as I might. I just can't get 3 legs of 440. I can get
two, but as soon as I try to dial in the wild leg, (using the taps) one of
the other legs goes high or low.

Any help appreciated

--
Peace
Milo
http://s235.photobucket.com/albums/ee67/mholroyd/