Lineair motion control advice

[Jochen]

Sjoerd,

compared to the NI-7330 the NI-7340 provides some more features like onboard programming, circular interpolation and contouring. Additionally you can configure each axis to control a stepper or a servo motor.
If you are just looking for a high-quality device for generating linear moves with a stepper motor and if you don't need the features mentioned above, you can use the NI-7330 (PCI-7332 in your case). The 7330 uses the same algorithms for controlling a stepper like the 7340, so you will get equal results (same accuracy and performance) with each of the boards.

Best regards,

Jochen

[Sjoerd1973]

Thanks again.

What are the advantages with onboard programming ?

I was "playing" with the motiion assistant, there fore I needed to install a virtual motion driver. I could only chose the 7340 series. Will this also work with the 7330, because Im just learning labview and this looks like the way to go to get a working solution.

I have a SCB-68 I/O connector  block (776844-01 ) and a SHC68-68-EPM Shielded Cable, 68-Pos. D-Type to 68-
Pos. VHDCI Offset ( 192061-01 ) that I used with a pci-6220 .

Can I use this I/O block to make connection to my hardware or are there better solutions.

I'm also nu sure that the cable will fitt. I tried to find out but got lost in al the different connection types.

Sorry for all the questions. I hope you can help me some more.

[Buechsenschuetz]

NI has a special "Universal motion interface" UMI-7764 (that's the one we have, there might be some other models, too), allowing for connecting all signals important for motion control via screw terminal blocks.

[Jochen]

Sjoerd,

1. Typically onboard programming is used to run some critical tasks independently from the host PC's CPU and operating system (e. g.  stopping the motor when a certain force limit is exceeded).
   
   
2. As long as you haven't used functions like arc moves or contouring moves, which are features that are only provided with 734x and 735x boards, you should be able to use your Motion Assistant Scripts with a 733x, too.
   
   
3. The SHC68-68-EPM cable is meant to be used with DAQ devices. Therefore the internal construction of the cable is optimized for minimizing cross-talk and noise for DAQ measurement tasks. The arrangement of the twisted pairs inside this cable is not optimized for the pinout of a motion board, but as long as your electical environment is not very noisy you might give it a try.
   
   In general cables that are designed to be used with NI-Motion boards provide better noise immunity. Similar arguments are true for the SCB-68. NI offers UMIs (Universal Motion Interfaces), like the UMI-7764 and the UMI-7772, that provide an advanced features set to improve cabling and signal integrity for motion applications. For more detailed information please refer to the UMIs' manuals that are linked on the product pages.

Jochen

[Sjoerd1973]

Thanks again for the fast reply.

I have 'to make up some time in this project. I ordered a pci-6220 and couldn't get that to work at all with my setup.  
I'm not a labview expert so experimenting with cable's and I/O blocks wich might give interference problems ... I better not try that. Thanks for the warning.

It is an experimental setup so  ithink the umi-7764 will give for more flexibility. I have no contouring or arc's just start stop and wait positions ( timed and manual trigger). The price difference between the 7332 and the 7342 are not that big. Do I get the same speed and accuracy from both cards when used only on a singel axis.

If correct the packet I need to order wil than be:
778924-02 NI PCI-7332 Low Cost 2 Axis Stepper Only Controller     
777978-02 UMI-7764(20Mhz Encoders)4Axis Mot Wiring Connectivity Mod No Cab.      
186381-02 SH68-C68-S 68-Pin VHDCI to 68-Pin. D-Type, 2m 

SJoerd

[Jochen]

Sjoerd,

yes, the performance and accuracy of the 7332 and the 7342 are equal. The 7342 is much more flexible than the 7332. So if there is a chance that you might want to use the motion board for applications with more advanced requirements, you may want to go for the 7342. If you are sure that the 7332 will always be used in your current setup, it is a good option.

The list of components makes sense. Please note that the UMI-7764 requires an external +5 V power supply as it comes with some active circuitry to provide signal filtering and security features that work independently from the PC.

Jochen

[Sjoerd1973]

Thanks a lot.

I think it will stay with this setup for a while and than .. maybe used for something similar. The servo drive maybe a nice extra to have so will debate over this before ordering.

The 5v suply had this to be a special  something or can this just be a 5v adapter or 5 v from a pc power suply ?

Gr Sjoerd

[Jochen]

The power supply for the UMI-7764 should be rated for at least 200 mA. For more information, please have a look at this thread.

Jochen

[Sjoerd1973]

Great. Only one simple encoder tht needs power so. A std 5v powersuply it will be.

Thanks for al the help !!

Sjoerd

[Sjoerd1973]

Still nut sure about the difference between de accuracy of the 7332 and the 7342.

When reading the website http://www.ni.com/motion/hardware_selection.htm  it states : Number of Axes per 62.5 µs PID Rate.

Does this impy that it is not possibel to get a pid on the 7332 and a lower accuracy ?

If so than I would maybe be better of with the 7342 and than the complete set would be:

 778916-02 NI PCI-7342, 2 Axis Stepper/Servo Motion Controlle
 777978-02 UMI-7764(20Mhz Encoders)4Axis Mot Wiring Connectivity Mod No Cab.
 186381-02 SH68-C68-S 68-Pin VHDCI to 68-Pin. D-Type, 2m

Thanks again for your answers.