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Where to start
#1
I have an Advantage 900 system with Turbo PMAC-2 Clipper. I've built CNC retrofit systems before but this one doesn't seem to have any sort of guide as to where to start. There seems to be three different software packages for configuration, one for the PMAC, one for the NC and then the NC/CNC software itself.

Any advice or guides available would be very helpful. My system consists of scales for the linear motors, x and z. A spindle with traditional encoder. Nothing complicated at all.
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#2
Here are some of the manuals and other resources to get you started:

Turbo Clipper Manual
Turbo PMAC User Manual
Turbo PMAC Software Reference Manual

Advantage 900 Manuals:
Pendant
PMAC NC Pro2 Software

Turbo PMAC Training Slides

If you have additional questions, please post them, or contact Technical Support at support@deltatau.com, or 818-717-5656, 8 am to 5 pm PST.
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#3
(09-24-2012, 02:04 PM)CharlesP Wrote: Here are some of the manuals and other resources to get you started:

Turbo Clipper Manual
Turbo PMAC User Manual
Turbo PMAC Software Reference Manual

Advantage 900 Manuals:
Pendant
PMAC NC Pro2 Software

Turbo PMAC Training Slides

If you have additional questions, please post them, or contact Technical Support at support@deltatau.com, or 818-717-5656, 8 am to 5 pm PST.

I have all the manuals but there is so much information in them and no real guide as to start here with this program or this step.
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#4
It is always recommended you attend the basic PMAC training course followed by the PMAC-NC training course before attempting an NC integration. A quick summary of the steps:

Step 1 - Setup of the PMAC controller. All of the following should be configured before moving on to any CNC setup:

- Jog all motors in closed loop (directions verified)
- Determine axis scaling (counts/unit)
- Home all motors successfully
- Determine all basic velocity/acceleration constraints of the system

Step 2 – Use NC Setup program to create initial CNC programs and PLC’s.
Step 3 – Modify the automatically created programs and PLC’s to suit your specific application.




(09-25-2012, 12:08 PM)PEERPSI Wrote:
(09-24-2012, 02:04 PM)CharlesP Wrote: Here are some of the manuals and other resources to get you started:

Turbo Clipper Manual
Turbo PMAC User Manual
Turbo PMAC Software Reference Manual

Advantage 900 Manuals:
Pendant
PMAC NC Pro2 Software

Turbo PMAC Training Slides

If you have additional questions, please post them, or contact Technical Support at support@deltatau.com, or 818-717-5656, 8 am to 5 pm PST.

I have all the manuals but there is so much information in them and no real guide as to start here with this program or this step.
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#5
(09-24-2012, 06:08 AM)PEERPSI Wrote: I have an Advantage 900 system with Turbo PMAC-2 Clipper. I've built CNC retrofit systems before but this one doesn't seem to have any sort of guide as to where to start. There seems to be three different software packages for configuration, one for the PMAC, one for the NC and then the NC/CNC software itself.

Any advice or guides available would be very helpful. My system consists of scales for the linear motors, x and z. A spindle with traditional encoder. Nothing complicated at all.

This is very basic


Attached Files
.pdf   Clipper Quick Start Guide - Proposed.pdf (Size: 668.54 KB / Downloads: 68)
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#6
It sounds like you are doing a lathe, or something like a lathe. I have done many lathes, albeit not with the clipper. Your first experience will be frustrating, but the final result will be really good. Here is what I would do:

I would consider going to training at Delta Tau if you really want to learn this stuff and have no Delta Tau experience. The training will mostly serve as an introduction and a forum for asking some high-level questions. If you simply want a working machine and don't care about learning it, hire a CNC Integration consultant, as this is not a trivial project. The people listed on the DT site are generally very good.

That said, here are the steps:

1. Make sure that you have all of the correct Delta Tau interface accessory hardware. People on this forum could help if you told us exactly what type of signal your amplifiers expect (U/V sinusoidal, for example? plus enable and fault, etc are there Hall signals for commution), exactly what type of signal your scales provdide (quadrature or sin / cos, for example), and any other critical signals (limit switches, what kind of signal). You need to make sure you have all the hardware you need. If you can't determine this information, you will likely not be successful.

2. Wire your machine using guidance from the the Clipper manual and the accessory hardware manuals and good engineering judgement. If you don't have adequate experience here, you will need professional help, or you won't be successful. Beware especially of poorly grounded, noisy signals. It will wreak havoc when you get to the NC integration part.

3. Set the jumpers for the Clipper per the manuals and install in the host PC. Install PEWIN32 or equivalent. Establish communications.

4. Configure each motor by setting the I variables in the controller and get to the point where the limit switches work, the amps can be enabled, and you can jog the motors. As they are linear motors you will have to learn about motor phasing and phase finding. You will have to learn how axis homing works. You will have to learn about how to scale an axis and set up a coordinate system (ultimately this will be X and Z). Set safety limits for following error, velocity, accel. Don't bother to think about the NC side until this is done. You will be debugging your wiring most likely during this phase. Save your configuration file often. Once again, DON'T BOTHER TO PROCEED UNTIL THIS PART IS MASTERED

5. Make a block diagram of everything your CNC machine should have, i.e. control panel, handwheel, spindle, coolant system.

6. Install the NC software as a Lathe and go through the configuration and download the required lathe.g and PLC programs (i.e. panel, handwheel, homing, it depends on your configuration). This will be hard to learn on your own, but it can be done. Start with minimal functionality and add features according to your block diagram. Don't try to make everything work at once. The best way is to take the supplied PLC programs and modify them only as necessary. Backup the registry and configuration file often.
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#7
Thanks for the advice so far. My system includes a Turbo PMAC Clipper, stand alone not PC card. My accessory boards are 8ES and 51S. It is a lathe and I'm using Sony B78 laser scales with a BD95-T32 preamp that produces 1vpp. Sunx NPN inductive proximity sensors for limits, they were already on the lathe. I have several years experience with Delta Tau PMAC's as the majority of our lathes in this particular department use them for NC control. I've also built several machines previous to this project using CNC systems from a couple of different manufacturers. Unfortunately getting to go on a factory course isn't an option for me. I will however follow the training material as provided in the link. Right now my concern is that when I use the Turbo PMAC setup application it is asking for my attached accessories. I'm not finding either of them as an option. I also understand there is a certain way they must be stacked. I have the 8ES directly ontop of the PMAC with the interpolar on top of it. I understand that with the high resolution 51S it is to be set up in the encoder tables rather then as an accessory.

My other question that I haven't been able to find a quick answer as to where to pick up the E-stop loop that is built into the Advantage 900. I've wired in a relay that will control a contactor feeding power to the amplifiers for my axis and spindle.

As for how my I/O is wired, I'm using Omega I/O converters to isolate the loads/signals from the PMAC card. They are very flexible and allow for a wide range of voltages on either side. To connect everything I'm using Phoenix cables and break out modules. They have connections for the 5 volts for instance. This should come from the PMAC card via the connectors or does it need to be seperately connected direct from the power supply. When I power up the PMAC and issue a reset from PEWIN the card responds but if I view the connectors the icons for voltage are not lit as I would expect.
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#8
Unfortunately, I am not a Clipper guy, so I don't know about issues daisy chaining the 8Es and 51s, but I will say that if you follow the information in the 51 documentation on encoder setup that it works.

Regarding +5VDC power for your I/O, I am a fan of using a separate, isolated supply. The PMAC can be jumpered for separate supply for the I/O The signals themselves should change state if you bring them to ground. You can test them by shorting the signals to ground and watching in PEWIN. Once you see that the card side is working, you can trace your signal path back.

Try reading examples of the E-stop plc. There are a number of ways to integrate this.

If it were me I would get the discrete I/O working at the PMAC level, then the encoders, then the amp control signals and DAC's, then worry about the e-stop integration. In the meantime, your hardware relay kill of the amps will provide safety. It sounds like you and I work on the same types of things. Feel free to email me if you would like to keep a dialog going.
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#9
Note that the Turbo PMAC setup software will not setup the ACC-51S. The setup program should be set to see this as a Turbo PMAC2 with the DAC interface option and quadrature encoders. Then use the Executives Encoder Conversion Table editor after using the setup program to establish the high resolution feedback (per the ACC-51S manual) and then retune the motors with the higher resolution feedback.

At this point use the NCSetup program (AUTOPILOT UTILITY) to generate the proper PLCs, Motion programs and registry entries to configure your paticular machine (see VINCEB's post).
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#10
See these two drawing for suggestions of how to interface your Estop chain to the Adv900 unit:

http://ftp.support.deltatau.com/DT-USA/N...%20(1).pdf

http://ftp.support.deltatau.com/DT-USA/N...%20(1).pdf

(09-27-2012, 03:26 AM)PEERPSI Wrote: Thanks for the advice so far. My system includes a Turbo PMAC Clipper, stand alone not PC card. My accessory boards are 8ES and 51S. It is a lathe and I'm using Sony B78 laser scales with a BD95-T32 preamp that produces 1vpp. Sunx NPN inductive proximity sensors for limits, they were already on the lathe. I have several years experience with Delta Tau PMAC's as the majority of our lathes in this particular department use them for NC control. I've also built several machines previous to this project using CNC systems from a couple of different manufacturers. Unfortunately getting to go on a factory course isn't an option for me. I will however follow the training material as provided in the link. Right now my concern is that when I use the Turbo PMAC setup application it is asking for my attached accessories. I'm not finding either of them as an option. I also understand there is a certain way they must be stacked. I have the 8ES directly ontop of the PMAC with the interpolar on top of it. I understand that with the high resolution 51S it is to be set up in the encoder tables rather then as an accessory.

My other question that I haven't been able to find a quick answer as to where to pick up the E-stop loop that is built into the Advantage 900. I've wired in a relay that will control a contactor feeding power to the amplifiers for my axis and spindle.

As for how my I/O is wired, I'm using Omega I/O converters to isolate the loads/signals from the PMAC card. They are very flexible and allow for a wide range of voltages on either side. To connect everything I'm using Phoenix cables and break out modules. They have connections for the 5 volts for instance. This should come from the PMAC card via the connectors or does it need to be seperately connected direct from the power supply. When I power up the PMAC and issue a reset from PEWIN the card responds but if I view the connectors the icons for voltage are not lit as I would expect.
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#11
(09-27-2012, 03:26 AM)PEERPSI Wrote: Thanks for the advice so far. My system includes a Turbo PMAC Clipper, stand alone not PC card. My accessory boards are 8ES and 51S. It is a lathe and I'm using Sony B78 laser scales with a BD95-T32 preamp that produces 1vpp....

The BD95s are kind of pricy for what they do. You should look at:
http://www.oztekcorp.com/products/interp...r-adapter/

Sony Scales, interpolated to 34 pm, Pmac, Sunx switches... Sounds familiar

Amplifier selection for this will be critical for this resolution: Low Noise, zero crossover distortion is a must.
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#12
(09-27-2012, 12:40 PM)JeffLowe Wrote:
(09-27-2012, 03:26 AM)PEERPSI Wrote: Thanks for the advice so far. My system includes a Turbo PMAC Clipper, stand alone not PC card. My accessory boards are 8ES and 51S. It is a lathe and I'm using Sony B78 laser scales with a BD95-T32 preamp that produces 1vpp....

The BD95s are kind of pricy for what they do. You should look at:
http://www.oztekcorp.com/products/interp...r-adapter/

Sony Scales, interpolated to 34 pm, Pmac, Sunx switches... Sounds familiar

Amplifier selection for this will be critical for this resolution: Low Noise, zero crossover distortion is a must.

I agree with you Mr. Lowe, amplifier performance (especially crossover performance) is a limiting factor these days. What amplifiers and power supplies can you recommend?
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#13
(09-27-2012, 10:11 AM)vinceb Wrote: See these two drawing for suggestions of how to interface your Estop chain to the Adv900 unit:

http://ftp.support.deltatau.com/DT-USA/N...%20(1).pdf

http://ftp.support.deltatau.com/DT-USA/N...%20(1).pdf

(09-27-2012, 03:26 AM)PEERPSI Wrote: Thanks for the advice so far. My system includes a Turbo PMAC Clipper, stand alone not PC card. My accessory boards are 8ES and 51S. It is a lathe and I'm using Sony B78 laser scales with a BD95-T32 preamp that produces 1vpp. Sunx NPN inductive proximity sensors for limits, they were already on the lathe. I have several years experience with Delta Tau PMAC's as the majority of our lathes in this particular department use them for NC control. I've also built several machines previous to this project using CNC systems from a couple of different manufacturers. Unfortunately getting to go on a factory course isn't an option for me. I will however follow the training material as provided in the link. Right now my concern is that when I use the Turbo PMAC setup application it is asking for my attached accessories. I'm not finding either of them as an option. I also understand there is a certain way they must be stacked. I have the 8ES directly ontop of the PMAC with the interpolar on top of it. I understand that with the high resolution 51S it is to be set up in the encoder tables rather then as an accessory.

My other question that I haven't been able to find a quick answer as to where to pick up the E-stop loop that is built into the Advantage 900. I've wired in a relay that will control a contactor feeding power to the amplifiers for my axis and spindle.

As for how my I/O is wired, I'm using Omega I/O converters to isolate the loads/signals from the PMAC card. They are very flexible and allow for a wide range of voltages on either side. To connect everything I'm using Phoenix cables and break out modules. They have connections for the 5 volts for instance. This should come from the PMAC card via the connectors or does it need to be seperately connected direct from the power supply. When I power up the PMAC and issue a reset from PEWIN the card responds but if I view the connectors the icons for voltage are not lit as I would expect.

Thanks for this. I was able to get my E-stop loop sorted this morning as a result. I'm hoping to have limits, halls and feedback sorted by the end of the day. Moving axis by Monday!

The linear motors and drives come from Aerotech, they are used on other machines we have here with success.
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#14
(09-28-2012, 06:09 AM)PEERPSI Wrote: The linear motors and drives come from Aerotech, they are used on other machines we have here with success.

Aerotech linears? BAL or BL 10-40? Those are good drives. In recent years they have been paying a lot of attention to biasing them for true AB operation. The bandwidth is not the greatest (1KHz), but workable and it's certainly an order of magnitude greater than the position bandwidth will be.

Also, pay close attention to your encoder signal levels. Saturation is much more harmful than a little S/N degradation that comes from a low amplitude.
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#15
(09-28-2012, 02:06 PM)JeffLowe Wrote:
(09-28-2012, 06:09 AM)PEERPSI Wrote: The linear motors and drives come from Aerotech, they are used on other machines we have here with success.

Aerotech linears? BAL or BL 10-40? Those are good drives. In recent years they have been paying a lot of attention to biasing them for true AB operation. The bandwidth is not the greatest (1KHz), but workable and it's certainly an order of magnitude greater than the position bandwidth will be.

Also, pay close attention to your encoder signal levels. Saturation is much more harmful than a little S/N degradation that comes from a low amplitude.

BL 10-40. I was actually considering buying their NC system complete but they couldn't put together a respectable pendant or jog station.

Finally put power to it today. Nothing worked save for the E-stop loop and my hydrostatic servo system. I love a challenge! I suspect the axis feedback failure is due to jumper settings, external versus internally powered. I/O I'm not sure yet. My Omega modules are showing triggered but the connector view shows nothing. One step at a time!
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#16
(09-28-2012, 08:53 PM)PEERPSI Wrote: Finally put power to it today. Nothing worked save for the E-stop loop and my hydrostatic servo system. I love a challenge! I suspect the axis feedback failure is due to jumper settings, external versus internally powered. I/O I'm not sure yet. My Omega modules are showing triggered but the connector view shows nothing. One step at a time!

E-Stop is an excellent first step!
When Delta Tau first set up the NC system they defined a whole new set of M variables, ignoring the suggested m variables in their manuals. For my work I have created an offset set of the general motor M variables starting at M1100. This allows most of the examples in the manuals to be used with only slight modification.
My order of testing would be to first verify feedback.
setup a watch window to look at the AqB counter of the ACC 51 and make sure it is getting ttl counts.
Add watch entries for the ADC channels of the 51 and see if sufficient amplitude analog signals are coming.
Next look at the flag inputs to verify your halls and limit/home switches.
Verify the encoder conversion table by observing the position display window.
Verify the phase counter is counting.
Open loop enable the drives and six step the motor verifying phasing direction and amplifier function.
Find a copy of the Hall Effect Phasing app note and follow it's procedure for determining the initial hall angle.

Some preliminary gains:
Ix08,Ix09=1
Ix30=100000
Ix31=2000
ix32=2005
ix33=50000
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#17
(10-01-2012, 05:13 AM)JeffLowe Wrote:
(09-28-2012, 08:53 PM)PEERPSI Wrote: Finally put power to it today. Nothing worked save for the E-stop loop and my hydrostatic servo system. I love a challenge! I suspect the axis feedback failure is due to jumper settings, external versus internally powered. I/O I'm not sure yet. My Omega modules are showing triggered but the connector view shows nothing. One step at a time!

E-Stop is an excellent first step!
When Delta Tau first set up the NC system they defined a whole new set of M variables, ignoring the suggested m variables in their manuals. For my work I have created an offset set of the general motor M variables starting at M1100. This allows most of the examples in the manuals to be used with only slight modification.
My order of testing would be to first verify feedback.
setup a watch window to look at the AqB counter of the ACC 51 and make sure it is getting ttl counts.
Add watch entries for the ADC channels of the 51 and see if sufficient amplitude analog signals are coming.
Next look at the flag inputs to verify your halls and limit/home switches.
Verify the encoder conversion table by observing the position display window.
Verify the phase counter is counting.
Open loop enable the drives and six step the motor verifying phasing direction and amplifier function.
Find a copy of the Hall Effect Phasing app note and follow it's procedure for determining the initial hall angle.

Some preliminary gains:
Ix08,Ix09=1
Ix30=100000
Ix31=2000
ix32=2005
ix33=50000

I've been trying to verify my axis limit switches, they work to the Omega convertors I'm using to isolate them from the card. My Sunx LS work on 12 volts and I understand the card expects 0-5. I expected to be able to see them as well as the halls in the View Connector window but it would appear they are not available there. I confirmed 5 VDC to my scale preamps from the 51S board, previously I confirmed sufficient amplitude at the preamp from the scales, however I'm not seeing any counts in the position screen. I considered using the watch screen but I'm not certain what address I should be looking at. I'd love to have the time to read the manuals cover to cover and figure it all out for myself but too many outside distractions. Every time I sit down to troubleshoot another fire breaks out some where else! However, today marks the start of a new week!
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#18
Encoder Addresses for ACC-51S

1 $C000 3 $C010 5 $C020 7 $C030
2 $C008 4 $C018 6 $C028 8 $C038
Channels 1 – 4 of the ACC-51S correspond to PMAC channels 1 – 4 if the ACC-51S is connected to the main PMAC2A-PC/104 board; channels 1 – 4 of the ACC-51S correspond to PMAC channels 5 – 8 if the ACC-51S is connected to the ACC-1P board.

ADC Addresses for ACC-51S

1 $FFC0 3 $FFC4 5 $FFC8 7 $FFCC
2 $FFC2 4 $FFC6 6 $FFCA 8 $FFCE
ACC-51S channels 1 – 4 become PMAC channels 1 – 4 if ACC-51S jumper E1 connects pins 2 and 3. ACC-51S channels 1 – 4 become PMAC channels 5 – 8 if ACC 51S jumper E1 connects pins 1 and 2.

I have my 8ES stacked ontop of the Clipper then the 51S. Does this then mean that my PMAC channels become 5-8? My jumper is still set to 2-3 as per factory default.

To view the values in a watch window I would select $FFCO for my first channel analog level and $C000 for my counts?
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#19
Okay limit switch variables found and limits confirmed. After talking to Steve M. I determined my cards where not stacked correctly and I needed to install the ribbon cable from the CPU to ACC-51S. Still no feedback though.

Also where do I look to confirm hall wiring?
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#20
Okay, halls confirmed. Turns out the suggested M variables aren't used with the Advantage 900 system and the 900 doesn't map the halls to an M variable. That is now done and they cycle as they should.

I returned my endoder conversion table back to 1/T extension of incremental encoder. Now I have counts. Unfortunately not the high resolution counts I need.

When I select high resolution interpolator PMAC2 style I get no counts.

Some progress is still progress!

So at this point I have limits, halls and feedback. If I can just get the high res feedback we can start moving motors!

Ideas anyone?
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#21
You will need to enter the address for the ADCs in the ECT editor as the drop down list does not have these. These are listed in the ACC-51S manual on page 16 (22 electronic). For the first channel (Servo IC 0 at $78000, first entry in the drop down list) this is $78800. Then set I103 and I104 to the "Processed Data Address" shown.
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#22
Thanks for that Steve. After our conversation I did read closer the 51S manual and made the appropriate entries manually. However after a $$$*** reset all returned back to what it originally was. I expect that there is some configuration file that is loading everything and I'll need to make my changes there. Working on that now.

Good thing is that after our conversation I got counts and I was able to set the direction as well.
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#23
I now have high resolution counts. I also now know the difference between $$$*** and $$$.

That said I'm not sure if I'm getting or understanding the number of counts I should be seeing. My scale has a period of 137.9 nanometres.

By my math that means I should have 1mm/.0001379x4096=29702683 or does the position screen show the software counts at 1mm/.0001379x128=928209?

In the NC setup program for counts per unit which would be the correct value?
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#24
(10-02-2012, 07:50 PM)PEERPSI Wrote: I now have high resolution counts. I also now know the difference between $$$*** and $$$.

That said I'm not sure if I'm getting or understanding the number of counts I should be seeing. My scale has a period of 137.9 nanometres.

By my math that means I should have 1mm/.0001379x4096=29702683 or does the position screen show the software counts at 1mm/.0001379x128=928209?

In the NC setup program for counts per unit which would be the correct value?

The ACC-51 interpolates your line resolution by 4096x, but the result is right shifted by 5 bits (/32) . Your "counts" /mm should be your line spacing/128. Be aware that Sony scales have a lot of variation in the actual line spacing and will need calibrating. They come with a calibration sheet listing the actual lines/mm, but in use these numbers require come adjustment. In the past we used a Moore step bar to do this, but now use an interferometer.
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#25
[/quote]

The ACC-51 interpolates your line resolution by 4096x, but the result is right shifted by 5 bits (/32) . Your "counts" /mm should be your line spacing/128. Be aware that Sony scales have a lot of variation in the actual line spacing and will need calibrating. They come with a calibration sheet listing the actual lines/mm, but in use these numbers require come adjustment. In the past we used a Moore step bar to do this, but now use an interferometer.
[/quote]

So I did a quick check with a gauge block to confirm my counts and it matches. So now I'm onto phasing/tuning the motors. We have movement but I have to get some parameter input data from Aerotech as what I have isn't adding up as far as motor pole spacing. I've also found out that the Turbo PMAC2 setup application will not work because of the inability to deal with the 51S high resolution interpolator. I expect this is also why my open loop move does not work in that application either.

In PMACPro tuning the open loop works, auto tune runs. However, step tests fail once I increase the step size to 1000000 counts. It gives me an FE error. If it wasn't for actual position matching commanded very well in the other step tests I'd suspect wrong direction.

Could my Ixx71 and Ixx70 be wrong? They were set based on the first few steps of the Turbo PMAC setup application.

Ideas anyone?
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#26
The Ixx70 should be set to 1, the Ixx71 should be set to the number of hardware counts per commutation cycle (not the shifted software counts), which is hardware counts/pole pitch. For the Trilogy motors the pitch is 2.4", don't remember for Aerotech. The acc-51 manual makes this real clear...I would look at that rather than use the utility software.
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#27
The manual is clear. After doing the math it would appear that my counts exceed the range of the variable. I'm thinking my only option here is to change the encoder decode from 4x to 2x.
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#28
(10-04-2012, 07:55 AM)PEERPSI Wrote: The manual is clear. After doing the math it would appear that my counts exceed the range of the variable. I'm thinking my only option here is to change the encoder decode from 4x to 2x.

Use the line counter i183=$78301. for your commutation counter.Counts/commutation cycle should be 1773382. You can verify this by:
I171=$8388607 ; max value
i129=2000
#1o0 ; at this point the motor will settle into a motor pole.
WX:$B4,0 ; zero the phase counter
;manually move the stage to the next motor pole
rx:$b4
; the pmac will report back the phase counter
; move the stage back and enter
i179 = 2000
rx:$b4
#1k ; important to kill motor.
if the count reported back by the read is a negative value the motor is considered to be phased positive and i172=683, otherwise it will be set to 1365

Set i129=0 and i179=0 and i171=1773382

Manual commutation:
if i172=683 set i179=2000 and #1o0
Let the motor settle into the motor pole and zero out the phase counter
WX:$B4,0
#1k
i179=0
(if i172=1365 set i179=-200 and do the phasing)
you should now be able to close the loop with #1j/
Set a reasonable slow speed, i122=500 and test with #1j+ and #1j-
if you can jog it through a commutation cycle then you are all set. if not go back and double check.
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#29
Ixx71 has a maximum value of 16,777,215 which means I would need to change my decode from 4x to 1x in order to deal with this. Is what you are recommending a way around that?
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#30
(10-04-2012, 11:03 AM)PEERPSI Wrote: Ixx71 has a maximum value of 16,777,215 which means I would need to change my decode from 4x to 1x in order to deal with this. Is what you are recommending a way around that?


No. I171= 2.4*25.4*lines/mm *4 (quadrature decode of the line counter)
=1773382
(assuming quadrature decode of 7 or 3 in the gate setup)
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#31
Much brain pain later I think I have it. I was using position value when I should have been using hardware counts.

Thanks again.
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#32
(10-04-2012, 12:44 PM)JeffLowe Wrote:
(10-04-2012, 11:03 AM)PEERPSI Wrote: Ixx71 has a maximum value of 16,777,215 which means I would need to change my decode from 4x to 1x in order to deal with this. Is what you are recommending a way around that?


No. I171= 2.4*25.4*lines/mm *4 (quadrature decode of the line counter)
=1773382
(assuming quadrature decode of 7 or 3 in the gate setup)

@ Jeff: 25.4 lines/mm (physical lines) for the Sony scales seems too coarse. What am I missing?
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#33
I think that was meant to convert the motor cycle length from inches to mm. 1 inch equals 25.4 mm.
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#34
At any rate, we are multi-threading at this point, but try using 1,905,000 counts/cycle per my other post (or if I have the wrong data for your encoder, scale it up or down)
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#35
Roger WILCO.

I'll try and keep my on going saga to just this thread.

Thanks.
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#36
(10-04-2012, 01:45 PM)tahoe brian Wrote:
(10-04-2012, 12:44 PM)JeffLowe Wrote:
(10-04-2012, 11:03 AM)PEERPSI Wrote: Ixx71 has a maximum value of 16,777,215 which means I would need to change my decode from 4x to 1x in order to deal with this. Is what you are recommending a way around that?


No. I171= 2.4*25.4*lines/mm *4 (quadrature decode of the line counter)
=1773382
(assuming quadrature decode of 7 or 3 in the gate setup)

@ Jeff: 25.4 lines/mm (physical lines) for the Sony scales seems too coarse. What am I missing?
Sorry I was not clear on that: counts/com= motor pole pitch (in mm) * lines/mm*4.
In the case of the BS-78 the lines/mm is ~6349
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#37
Jogged both axis last night. Next step make them home and then more tuning with the loads on board.

Pretty soon we'll have ourselves a lathe!

Thanks.
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#38
(10-04-2012, 10:56 AM)JeffLowe Wrote: Use the line counter i183=$78301. for your commutation counter.Counts/commutation cycle should be 1773382. You can verify this by:
I171=$8388607 ; max value
i129=2000
#1o0 ; at this point the motor will settle into a motor pole.
WX:$B4,0 ; zero the phase counter
;manually move the stage to the next motor pole
rx:$b4
; the pmac will report back the phase counter
; move the stage back and enter
i179 = 2000
rx:$b4
#1k ; important to kill motor.
if the count reported back by the read is a negative value the motor is considered to be phased positive and i172=683, otherwise it will be set to 1365

Thanks again Jeff. I went through your steps listed above and I was able to confirm that the counts were close to what I calculated for my scales.

In the case of X 1767853 with a comp value of 2999. For this one the procedure above returned values with in 1 or 2 of I171.

In the case of Z 1767811 with a comp value of 3331. For this one the procedure above returned values with in +/- 44 of I271.

Axis jog and will pass the open loop test and step tests seem okay.

However I seem to be having trouble with following error. If it is enabled, even with a very high value I get FE every time. When jogging and watching the FE seems to go no higher then 4000.

I'm wondering if I have some feedback address wrong as to where it reads the following error.

I've tried homing and then does not work yet either. I need to confirm that the control is seeing the index signal from the scale but I'm not sure where to look for that.
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#39
(10-15-2012, 11:45 AM)PEERPSI Wrote: However I seem to be having trouble with following error. If it is enabled, even with a very high value I get FE every time. When jogging and watching the FE seems to go no higher then 4000.

I'm wondering if I have some feedback address wrong as to where it reads the following error.

I've tried homing and then does not work yet either. I need to confirm that the control is seeing the index signal from the scale but I'm not sure where to look for that.

Do some gathers while jogging at a couple of different constant speeds. (When doing this don't use exact multiples of speed) Look at the plots and see if there is any structure to them. Do an fft and look for spikes in the FE. Low frequency is probably tuning, A constant high frequency is most likely a natural in the system. try lowering the derivative gain. A high frequency that changes with speed may be related to scale adjustment. I don't know if delta tau has an app note on how to use the diagnostic modes of the acc51 encoder table entries to generate the proper scale offset values.
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#40
Keep in mind when using acc-51 feedback PMAC software counts are 32 times bigger than quadrature hardware counts:
1 line = 4 hardware counts = 128 software counts = 4096 states (LSBs)
¼-line = 1 hardware count = 32 software counts = 1024 states (LSBs)
1/128-line = 1/32-hardware count = 1 software count = 32 states (LSBs)
1/4096-line = 1/1024-hardware count = 1/32-software count = 1 state (LSB)
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#41
(10-16-2012, 11:25 AM)steve.milici Wrote: Keep in mind when using acc-51 feedback PMAC software counts are 32 times bigger than quadrature hardware counts:
1 line = 4 hardware counts = 128 software counts = 4096 states (LSBs)
¼-line = 1 hardware count = 32 software counts = 1024 states (LSBs)
1/128-line = 1/32-hardware count = 1 software count = 32 states (LSBs)
1/4096-line = 1/1024-hardware count = 1/32-software count = 1 state (LSB)

signal period is .00013792999 mm.
I calculate as follows:
1/.00013792999*4=29000 hardware counts per mm.
1/.00013792999*128=928007 software counts per mm.
1/.00013792999*128*60.96=1767853 hardware counts per motor cycle

With an I122 of 5000 I see about max 4000 cts FE on the position screen. Yet with I111 set to 4000000 I get an FE error when trying to do the maximum step size in the Pro Tune application.
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#42
Tuning can produce significant FE during the beginning stages until the motor becomes “well tuned”. We suggest increasing the fatal FE variable, Ixx11, until the issue subsides. Once the motors are well tuned you can set the Ixx11 back to a reasonable value for your application.
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#43
Keep in mind that I111 is in units of 1/32 of a count, so you are actually setting your limit to about 125,000 counts, which is not that big if you are doing step inputs with the FE limit enabled.

Your 4000 count FE while jogging slowly is not huge, but is not small either. What is the FE if you just close the loop and not try to move it?

As Jeff said above, if you can look at an FFT of the FE signal it will tell us more about what might be happening. Can you do this?

Another thing that would be helpful would be to tell us what the gains (Ixx30-Ixx39) currently are set to. Then, do a test where you close the loop with no jogging, and keep raising the Ixx30 until it goes unstable and starts to whine, or the FE trips. Raise it about 10% at a time. That would tell me some things about where things stand with the loop gain. Perhaps report the "typical" max FE at each gain as seen by a watch window.

Questions: was this machine positioning well before the retrofit? Is it air bearing or oil hydrostatic? Do you know what the gains were on the original D-T controller?
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#44
(10-17-2012, 12:58 PM)tahoe brian Wrote: Keep in mind that I111 is in units of 1/32 of a count, so you are actually setting your limit to about 125,000 counts, which is not that big if you are doing step inputs with the FE limit enabled.

Your 4000 count FE while jogging slowly is not huge, but is not small either. What is the FE if you just close the loop and not try to move it?

4000 counts with the LaserScales is roughly 4 microns which is quite large for a non-contact system. Ours we typically run 0.2-0.5 "counts" static and 2-5 "counts" jogging at constant speeds. Side note: I gave you a set of gains earlier in this thread, but I neglected to mention that we are using a 5 KHz servo update. You will probably want to operate at this rate as well.
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#45
I agree with you Jeff, 4000 counts is much larger than where he will end up, but still under some level of control, hence, my comment. Just so I am clear on which definition of counts that we are using here , isn't one servo error count = 34 picometers, and thus 4000 counts = 136 nanometers, or are we talking that the LSB is a fractional count? Please straighten me out.
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#46
Counts are quite high and I expect to sort that out with further tuning. Typically on our older lathes we look for 15 counts max at 7MM travel rate. On the newer, less then 5. Of course we struggle to make sure ports are clean, lifts are correct, way covers are not dragging, hoses and cables are in good repair. Then the operator fails to balance the spindle correctly! Argh!

The machine uses hydrostatic bearing system. It floats well and the way covers are not yet reinstalled. The lathe was easily able to achieve less then 15 counts FE before tear down. Problem is the ball nut was isolated via the hydrostatic system to prevent vibration transfer. That system was tough to get working right and didn't seem to stay right. This of course means that the stiffness numbers were quite low. Linear motors have been installed which should correct that part of the problem.

Today I managed to confirm that the lathe is seeing it's index mark, set up the limit switches and figured out how to get it travelling and incrementing in the correct direction. However, some how I've managed to inadvertentlly cause the second axis to have a positive limit fault. Won't even phase. It's not the hardware limit as I can see the limits toggle in a watch window. When I try and disable the soft limits, I213 it will not accept my input. I try setting it to zero to disable it but something is over riding it. Shouldn't be the PLC as I've not touched that yet. Axis did work yesterday.

FE error is hardware or software counts? I'm thinking hardware same as what the position window displays.

Hopefully tomorrow I can have homeing and limits working right so I can start getting serious about tuning and get the FE counts down.

Again gentlemen thanks for your input. I'm learning lots!
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#47
(10-17-2012, 01:53 PM)JeffLowe Wrote: I gave you a set of gains earlier in this thread, but I neglected to mention that we are using a 5 KHz servo update. You will probably want to operate at this rate as well.

I7000?
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#48
(10-17-2012, 02:48 PM)tahoe brian Wrote: I agree with you Jeff, 4000 counts is much larger than where he will end up, but still under some level of control, hence, my comment. Just so I am clear on which definition of counts that we are using here , isn't one servo error count = 34 picometers, and thus 4000 counts = 136 nanometers, or are we talking that the LSB is a fractional count? Please straighten me out.

The high resolution option for the ACC 51e in the encoder conversion table right shifts the data 5 bits into the "fractional" part of the position word. One "count" is 32 least significant bits so one "count" is 32*34 pm or around 1 nm. It is quite possible to issue a #1J:0.03125 and the commanded position will advance by 34 pm. Similarly #1j:1 will advance the commanded position by 32 least significant bits (or around 1 nm). This is all good as carrying around an empty 5 bit fraction field adds nothing to system stability or resolution. Right shifting the data does not loose anything and helps a lot at high velocities which can easily saturate in high resolution systems.
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#49
(10-17-2012, 06:38 PM)PEERPSI Wrote:
(10-17-2012, 01:53 PM)JeffLowe Wrote: I gave you a set of gains earlier in this thread, but I neglected to mention that we are using a 5 KHz servo update. You will probably want to operate at this rate as well.

I7000?

I10=1677511
I7200-5896
i7201=0
i7202=3
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#50
(10-18-2012, 05:50 AM)JeffLowe Wrote: I10=1677511
I7200-5896
i7201=0
i7202=3

I had looked at those and wasn't sure. Thanks for setting me straight.
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