Suitability of the PXIe 6612 Encoder Positioning Module

[tomjericho]

Hi,
I'm trying to record encoder signals from a motor driver (Pansonic Minas A5) to determine the current position of the motor. My current hardware includes a PXI 8108 embedded controller. Is it possible to reliably record encoder signals with a minimum pulse width of 200ns using the PXIe 6612 module? If so, what accessories are required? I have been shown a cable (SH-68-68-D1) and a connector block (SCB-68A) on the website as a necessary accessory.
Could someone also help me on  how to  connect the encoder signal cables to the module or the terminal block?
(The encoder is differential)
If someone has another solution, I would be open to it.

Link PXIe 6612: https://www.ni.com/en-us/shop/details/pr...nContext=1

Thanks in advance.
tomjericho

[Kevin_Price]

You'll also need to convert the differential encoder signals to single-ended TTL to be compatible with your 6612 device.

Once you have compatible signals, the wiring options are quite flexible, allowing you to configure your counter to use most any PFI pin you choose for your counter measurement task.  As a starting point, here's a link to the standard SCB-68 labelling for 66xx series counter devices, which identifies the default PFI pins for various functional purposes.  (Though again, you can program it otherwise if you want.)

-Kevin P

[tomjericho]

Thanks for the answer. Do you know if there isa PXI Module form National Instruments, that supports differential encoders? 

If not, how do I convert the signal from differential to single ended? 

Sorry, I am very to this.

Greetings

helloitsme

[Kevin_Price]

I'm not aware of a PXI module that would support differential encoder signals directly, but don't take that as the final word.  I have fairly limited knowledge of the range of PXI devices.

I don't have a specific converter in mind, but you can find a lot of candidates with some searching.  You might also get some help and guidance from the encoder manufacturer.  It's possible they can recommend a known-compatible converter.

Note that it'll be a good idea to put the converter close to the DAQ device so that the longer wire run carries the differential signals while the shorter wire run carries single-ended.

-Kevin P

[tomjericho]

Would this part work as a converter for the A and B Phase?

https://www.mouser.de/ProductDetail/Texas-Instruments/UA9637ACD?qs=IF4wzcbwb3qaafFn%252BLgiQQ%3D%3D&...

Greetings

[Kevin_Price]

The TTL output side and speed rating look good, but I don't know if your encoder uses the RS-422 "flavor" of differential that this chip is made for.  You'll need to confirm with your encoder spec sheet.

Understand too that the money saved by buying a cheap raw chip turns into a lot more fussing about trying to integrate and make it robust in your test setup.

-Kevin P

[tomjericho]

Okay I will check the output signal type. 

My Motor and Driver are a Panasonic Minas A5. 

I was looking for other plug and play modules, but I couldn't find any better solutions for a converter. They were all for 24V Signals or from India, where I can't order from. 

What exactly do you mean? Do I have to pay attention to anything special. I was just going to solder the 4 input cables from the encoder (A+, A-, B+, B-) to the chip and then solder two cables from the chip (A and B) to a SCB-68A Block. 

And then add a 5V Powersupply to the chip. 

Is that possible that way?

Greetings

[Kevin_Price]

Caveat:  electronics isn't really my thing.

The "fussing about" I referred is several things. 

1. building up the chip into whatever full circuit is needed.  (I didn't explore this one deeply -- many, but not all such chips will have a more complete recommended circuit that incorporates a few additional components like resistors and caps.)

2. possibly fragile solder connections, until you also add strain relief and packaging of the little circuitboard

Basically, the fact that you don't mind dealing with the soldering suggests to me that there's no further problem here to worry about.  It's just that not everyone is up for dealing with component-level electronics this way.

-Kevin P

[tomjericho]

Okay, thanks for the explanation. 
I think it will fit my needs. 

I will give an Update in this Forum, when I have tried the parts

Greetings