A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

For some reason, two resolver leads (two from separate stators) were
interconnected. At first I thought that I could reuse that old
arrangement instead of the lead pairs being fully isolated and
differential.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

As of now, not much has been done after ripping things out, but
perhaps tonight I will get 25% of work done.

i

On 2010-12-28, PrecisionmachinisT wrote:
That resolver model is used as feedback on your typical Fadal DC rotary axis
system.

Did not know

If you still have the pigtail I would perhaps buy it from you if the price
is right and provided it is a -35pin male milspec connector.

What pigtail are you talking about?

FWIW, almost nobody pays Danaher their listed retail price for
resolvers--last time I bought a new one IIRC I paid around $230 for
it...Also, at least one of the Fadal service houses offers "rebuilt"
resolver units for around $120 last I checked.

Rather than considering use of a resolver at all I would suggest go to a
encoder instead if it is at all possible--size 11 resolvers are highly prone
to rapid bearing failure given even the slightest shaft misalignment and
they will also will develop an internal open circuit at basically the drop
of a pin.

What I know is that this particular resolver is mounted the way it was
originally mounted. Since this is a troyke table, I expect they did a
good job at mounting.

I thought a lot about resolver vs encoder issue, and right or wrong,
decided that I want to reuse the resolver with "resolver converter".

i

"Ignoramus24647" wrote in message
...
On 2010-12-28, PrecisionmachinisT wrote:
That resolver model is used as feedback on your typical Fadal DC rotary
axis
system.

Did not know

If you still have the pigtail I would perhaps buy it from you if the
price
is right and provided it is a -35pin male milspec connector.

What pigtail are you talking about?


35 pin male amphenol

Mil-C-5015

Similar to :

http://www.cadillacproducts.com/images/CN_Series.jpg

FWIW, almost nobody pays Danaher their listed retail price for
resolvers--last time I bought a new one IIRC I paid around $230 for
it...Also, at least one of the Fadal service houses offers "rebuilt"
resolver units for around $120 last I checked.

Rather than considering use of a resolver at all I would suggest go to a
encoder instead if it is at all possible--size 11 resolvers are highly
prone
to rapid bearing failure given even the slightest shaft misalignment and
they will also will develop an internal open circuit at basically the
drop
of a pin.

What I know is that this particular resolver is mounted the way it was
originally mounted. Since this is a troyke table, I expect they did a
good job at mounting.

I thought a lot about resolver vs encoder issue, and right or wrong,
decided that I want to reuse the resolver with "resolver converter".


Well, if I could find a converter that allows replacing the resolvers here
with an encoder likely that I would immediately purchase about ten of
them--because I have about 6 bad resolvers mostly harowe from glentek motors
in my desk drawer but have yet to see a single encoder failure on fanuc
motors.

On 2010-12-28, PrecisionmachinisT wrote:

"Ignoramus24647" wrote in message
If you still have the pigtail I would perhaps buy it from you if the price
is right and provided it is a -35pin male milspec connector.


What pigtail are you talking about?


35 pin male amphenol
Mil-C-5015
Similar to :
http://www.cadillacproducts.com/images/CN_Series.jpg

Do not have one

FWIW, almost nobody pays Danaher their listed retail price for
resolvers--last time I bought a new one IIRC I paid around $230 for
it...Also, at least one of the Fadal service houses offers "rebuilt"
resolver units for around $120 last I checked.

Rather than considering use of a resolver at all I would suggest go to a
encoder instead if it is at all possible--size 11 resolvers are highly
prone
to rapid bearing failure given even the slightest shaft misalignment and
they will also will develop an internal open circuit at basically the
drop
of a pin.

What I know is that this particular resolver is mounted the way it was
originally mounted. Since this is a troyke table, I expect they did a
good job at mounting.

I thought a lot about resolver vs encoder issue, and right or wrong,
decided that I want to reuse the resolver with "resolver converter".


Well, if I could find a converter that allows replacing the resolvers here
with an encoder likely that I would immediately purchase about ten of
them--because I have about 6 bad resolvers mostly harowe from glentek motors
in my desk drawer but have yet to see a single encoder failure on fanuc
motors.

Do you know how hard is it to drill and tap a shaft of that servo
motor, coaxially, to install a stem to mount the encoder disk?

Is the shaft hardened?

i

"Ignoramus24647" wrote in message
...

Do you know how hard is it to drill and tap a shaft of that servo
motor, coaxially, to install a stem to mount the encoder disk?

Is the shaft hardened?


Motor shafts are generally fairly soft in my experience though I suggest
check and see if it can be easily molested with a file.

I would probably spin in a lathe using a roller support opposite the chucked
end and spot, drill then ream.




--

On 2010-12-28, Ignoramus24647 wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

For some reason, two resolver leads (two from separate stators) were
interconnected. At first I thought that I could reuse that old
arrangement instead of the lead pairs being fully isolated and
differential.

Probably for experimentation without long signal leads.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.

--
Remove oil spill source from e-mail
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On 2010-12-29, DoN. Nichols wrote:
On 2010-12-28, Ignoramus24647 wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

I have NO idea, this is a good question. I wondered about the same thing.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

Yes, this is what I tried to say, every pair is shielded.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.


thanks.

Any thoughts on this excitation frequency?

i

In article ,
Ignoramus24647 wrote:

On 2010-12-29, DoN. Nichols wrote:
On 2010-12-28, Ignoramus24647 wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-2-CNC-Mill/24
-Troyke-Rotary-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

I have NO idea, this is a good question. I wondered about the same thing.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

Yes, this is what I tried to say, every pair is shielded.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.


thanks.

Any thoughts on this excitation frequency?

Whatever the resolver wants. The datasheet provided above says 400 Hz
through 2500 Hz. I bet it is not critical within that range, but 10 KHz
is too high. I would ask Pico. Much more important to accuracy than
excitation frequency is good shielding.

Joe Gwinn

Ignoramus24647 wrote:
On 2010-12-29, DoN. wrote:
On 2010-12-28, wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

I have NO idea, this is a good question. I wondered about the same thing.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

Yes, this is what I tried to say, every pair is shielded.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.


thanks.

Any thoughts on this excitation frequency?

i


I believe that that board has a freq select jumper and the max freq is 10kc.

John

On 2010-12-29, John wrote:
Ignoramus24647 wrote:
On 2010-12-29, DoN. wrote:
On 2010-12-28, wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

I have NO idea, this is a good question. I wondered about the same thing.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

Yes, this is what I tried to say, every pair is shielded.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.


thanks.

Any thoughts on this excitation frequency?

i


I believe that that board has a freq select jumper and the max freq is 10kc.

John

That is the min frequency.

i

On 2010-12-29, Joseph Gwinn wrote:
In article ,
Ignoramus24647 wrote:

On 2010-12-29, DoN. Nichols wrote:
On 2010-12-28, Ignoramus24647 wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...-2-CNC-Mill/24
-Troyke-Rotary-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

I have NO idea, this is a good question. I wondered about the same thing.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

Yes, this is what I tried to say, every pair is shielded.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.


thanks.

Any thoughts on this excitation frequency?

Whatever the resolver wants. The datasheet provided above says 400 Hz
through 2500 Hz. I bet it is not critical within that range, but 10 KHz
is too high. I would ask Pico. Much more important to accuracy than
excitation frequency is good shielding.

Joe Gwinn

I use a multiconductor cabnle where each pair is shielded.

i

In article ,
Ignoramus26424 wrote:

On 2010-12-29, Joseph Gwinn wrote:
In article ,
Ignoramus24647 wrote:

On 2010-12-29, DoN. Nichols wrote:
On 2010-12-28, Ignoramus24647
wrote:
A couple of days ago, I started working on getting my 4th axis rotary
table to work.

http://igor.chudov.com/projects/Brid...act-2-CNC-Mill
/24
-Troyke-Rotary-Table-U12PNC/

I mounted it on the milling table a while ago and started integrating
it on Sunday or thereabouts. Constantly being interrupted by the
family, of course.

For feedback, it has a separate tachometer and a "resolver". This
resolver has six leads, two for rotor excitation and two for stator.

http://igor.chudov.com/manuals/Harow...300-F10-10.pdf

I would use Jon's resolver to encoder converter board:

http://pico-systems.com/resolver.html

Hmm ... the resolver has specs at 400 Hz (aircraft use) and at
2.5 KHz -- but the board seems to want to talk at 10 KHz. Any certainty
that this one will handle the 10 KHz frequency?

I have NO idea, this is a good question. I wondered about the same thing.

Yesterday I had a revelation and changed my mind. I decided that an
extra week spent on doing things the right way would be time well
spent. I decided to replace the terminal strip on the rotary table
to accommodate completely isolated stators, add a connection for home
switch, etc.

So I ripped everything apart again and will use a 12 lead cable, with
every lead pair shielded individually.

Hmm ... I would instead put each of the secondary windings from
the resolver in a separate shielded twisted pair instead of individual
leads shielded. Better common mode rejection.

Yes, this is what I tried to say, every pair is shielded.

1) 6 wires (3 pairs) for the resolver
2) 2 wires for the tachometer
3) 2 wires for home switch
4) (possibly) 2 wires for limit switch.

Best of luck,
DoN.


thanks.

Any thoughts on this excitation frequency?

Whatever the resolver wants. The datasheet provided above says 400 Hz
through 2500 Hz. I bet it is not critical within that range, but 10 KHz
is too high. I would ask Pico. Much more important to accuracy than
excitation frequency is good shielding.

Joe Gwinn

I use a multiconductor cable where each pair is shielded.

That's good and usually necessary. Pico may have an opinion on how best
to connect the shields and pairs so the capacitance from pair to shield
has little effect. The point of the shielding is to prevent leakage of
excitation drive signals into the signals coming from the resolver,
which will cause phase shifts and thus angle errors.

The resolver angular accuracy is +/- 10 minutes of arc, according to the
datasheet. If we assume leakage in quadrature with the true signal,
then leakage ratio exceeding Tan[10' of arc]= 0.0029:1 voltage, or about
-51 dB will cause that magnitude of error. Now, it is not hard to
achieve this much shielding effectiveness, if one does a reasonable job.

Joe Gwinn