Propriatary AC servos into universal AC servos with an encoder swap?

Ok, Ive tried to post photobucket pics in every way imaginable and just gave up, so sorry for the lack of visuals (tips to accomplish this very welcome)

Anyway, I have several really great AC servos laying around but unfortunately im still learning the basics (I can make steppers work in my sleep and am currently studying DC and BLDC servos). But it seems like high-end AC servos are in a world of their own. Many are proprietary and will only work with drivers they were specifically designed to work with. On top of that it seems that many dont like the step/dir signals given by most of our hobby controller software and require tweaks and mods to work with our machines...However...

Can we simplify this by replacing the encoders with a more commonly supported version like the old HEDS or the new CUI capacitive encoders? Linear would be awesome as well. The majority of these servos have 4 pin connectors powering the motors so that may help. So in theory, would we be able to simplify these unity with an encoder swap and open the door to using more general/common/ less expensive servo drives?

Many thanks!

There are basically two types of brushless servo, BLDC with hall style commutation and AC with sinusoidal commutation, in general the former are easier to mix and match drives to.
The BLDC usually have either true hall effect devices or equivalent tracks on the encoder.
AC sinusoidal come with a few variations, but are often fitted with a resolver, which makes it a great deal harder to match up.
In the past I have removed the proprietary encoders on Fanuc AC types and fitted them with a BLDC commutation encoder.
If they are BLDC motors, then A-M-C or Aerotech or Copley drives can be used, but analogue input. There are others if you want step/dir.
I have tried the CUI brushless types and could not get consistent performance of the standard optical type encoder.
Al.

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Originally Posted by Al_The_Man

There are basically two types of brushless servo, BLDC with hall style commutation and AC with sinusoidal commutation, in general the former are easier to mix and match drives to.
The BLDC usually have either true hall effect devices or equivalent tracks on the encoder.
AC sinusoidal come with a few variations, but are often fitted with a resolver, which makes it a great deal harder to match up.
In the past I have removed the proprietary encoders on Fanuc AC types and fitted them with a BLDC commutation encoder.
If they are BLDC motors, then A-M-C or Aerotech or Copley drives can be used, but analogue input. There are others if you want step/dir.
I have tried the CUI brushless types and could not get consistent performance of the standard optical type encoder.
Al.

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Ah nice. Thanks for the info. So AC servos require a resolver in addition to the encoder? Are there any drives that are somewhat "universal" when it comes to AC servos? I'd love to give the brushless servos a crack but bought a bunch of small AC servos without knowing how difficult it would be for a hobbiest like me to figure it all out. I have some Yaskawa SGMP 100W 200V servos that I plan to use on my X2 cnc mini mill. After coming across exactly zero examples of how this can be done I started looking at other options.

The resolver also serves as encoder, the count is extracted by using the arctangent function on the two sine waves out.
Unless the motors are BLDC, it can be tricky.
Al.

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Originally Posted by SwampDonkey

.....Are there any drives that are somewhat "universal" when it comes to AC servos?.....

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Yes.

Kollmorgen servo drives typically accept resolvers, TTL encoders, 24vdc output encoders, sine encoders, linear scales, absolute encoders (Heidenhain Endat, BISS, Hypermach, SSI, some others) some even sensorless - all in the same drive. But it is typically a $ 1000 drive not a $ 100 one. I have run about every motor mfgr'es motors with these - if they have one of these feedbacks. Like you, we have removed proprietary feedbacks like fanuc/some-yaskawa and replaced them with encoders or resolvers. We do retrofits on machines no one else can do because of it. We even proved we can run Dc brush motors with only tach feedback with some of our standard AC Kollmorgen servo drives.

Well, Ive spent about a grand so far on Yaskawa motors and drives only to find that they're incompatable, or wont run well when given step/dir signals from Mach3. I figured there must be a way yo make it work. The solution eludes me.

Barring the out-of-my-budget kollomorgan drives, are there any options? Ive seen guys make small circute boards and add resistors here and there to make servos work but im no electrical engineer (fluids, actually).

Would something like this:
http://www.ebay.com/itm/4-Axis-USB-C...item2ec569a360

run these servos:

http://www.ebay.com/itm/151000299847...84.m1497.l2649

with drivers like these?

http://www.ebay.com/itm/Leadshine-DC...item1c30cfbcb8



Im new to servos, and everything I spend a week's pay on turns out to have some hidden aspect that makes it incompatable with what I have:(

Please help. I really want to break into the world of servos but would like to get something working.

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Originally Posted by mike_Kilroy

Yes.

Kollmorgen servo drives typically accept resolvers, TTL encoders, 24vdc output encoders, sine encoders, linear scales, absolute encoders (Heidenhain Endat, BISS, Hypermach, SSI, some others) some even sensorless - all in the same drive. But it is typically a $ 1000 drive not a $ 100 one. I have run about every motor mfgr'es motors with these - if they have one of these feedbacks. Like you, we have removed proprietary feedbacks like fanuc/some-yaskawa and replaced them with encoders or resolvers. We do retrofits on machines no one else can do because of it. We even proved we can run Dc brush motors with only tach feedback with some of our standard AC Kollmorgen servo drives.

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The USB controller outputs step/dir, the drive takes s/d and the voltage current rating appears to be capable for the motor.
Al.

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Originally Posted by Al_The_Man

The USB controller outputs step/dir, the drive takes s/d and the voltage current rating appears to be capable for the motor.
Al.

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Well that sounds like good news. Is there any way to be sure of compatibility before plunking down a bunch more money? im accumulating a small fortune in parts I cant use....

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Originally Posted by SwampDonkey

Well that sounds like good news. Is there any way to be sure of compatibility before plunking down a bunch more money? im accumulating a small fortune in parts I cant use....

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At least one: list the EXACT motor part number you want to run or better yet, also a manual showing what the part number means. Yaskawa, like many other motor mfgrs, builds motors with many different type feedback devices: without explicitly telling us the exact feedback type in YOUR motor, there is no guarantee a given motor can be run with a given drive......

SwampDonkey

What are the Yaskawa drives & motors numbers /letters that you have, they most likely are OK