mesa 7i97T + 7i84U

Hello.I have a cnc sharpener with motors and Italian analog servo drivers -10V Phase AX-V 06094. I want to upgrade to linuxcnc since the controller is an old PROMAX system that has an old SD card reader, it does not support modern sc cards. Some cards I have have errors and there are no spare parts. I think the phase drives are connected to SINCOS encoders, the driver has encoder outputs Ch A, Ch. B and Ch. C (Ch C seems to be index) the outputs are NPN open collector 30 V, 100 mA. Is it possible to connect these drivers to a 7i97T table card?, and also advice to expand the inputs since the 7i97T only has 16, I had thought about a 7i84U card.


Sorry if it's not right in English, my language is Spanish.  

You can connect single ended NPN encoder outputs to the 7I97T
Worst case you might need a stiffer pullup resistor on the inputs
than the built in 2K ohm encoder input pullups on the 7I97T

A 7I84U (32 inputs 16 outputs)  or a 7I70 (48 inputs) can be used to expand the inputs on a 7I97T

Thanks for responding.

Cables 14, 15 and 16 are used in the machine.
I wasn't planning to touch the cables between the driver and the encoder, they have 16 or 17 cables.

It hasn't been clear to me about the resistors:

What value should the resistors have and what power should they dissipate?
4.7 ohm and 1/2 W resistors would be okay?
And I understand that they must be connected between the 5V pin of 7i97T and the QA, QB and IDX pins.

angelnu wrote:

It hasn't been clear to me about the resistors:

What value should the resistors have and what power should they dissipate?
4.7 ohm and 1/2 W resistors would be okay?
And I understand that they must be connected between the 5V pin of 7i97T and the QA, QB and IDX pins.
 

470 Ohms 1/4W  would be a good value (~10 mA) 
(4.7 Ohms is way too low = ~ 1A)

Sorry, I meant 4.7K

Ok I will buy it at eusurplus on their website they have it in stock, I live in Spain.
Thank you very much for your answers