Servo Motors with TTL Differential, Incremental...

Lately is getting harder to find a Servo Motors with TTL Differential, Incremental encoder. Does anyone in this forum knows any suppliers that might have this type of motors?

I already have the servo drives with me, now I need to purchase the servo motors compatible with it. These are the specifications. Any help will be highly appreciated.

AC Brushless Servo Drive
Lenze Americas: Model "PositionServo" #E94P040Y2NEM
Continuous Current | Drive Rating in Amps = 4 Amps
Peak Current 12 Amps
Actual input voltage range: 80VAC to 264VAC, 1Ø
Number of Pole = Eight (8)
MOTOR FEEDBACK | ENCODER:
TTL Differential, Incremental encoder with Hall emulation tracks or Hall sensors necessary for commutation with resolution of 2000 PPR or higher

A link to the specs and manual are here:

dl.dropbox.com/u/58111636/PositionServo%...0Hardware%20V2.0.pdf

dl.dropbox.com/u/58111636/Lenze%20Servo%...oduct%20Brochure.pdf

I tend to make my own encoders and fit them to the ball screw.
www.wallacecompany.com/cnc_lathe/HNC/00001-1a.jpg
www.wallacecompany.com/cnc_lathe/HNC/00011-1a.jpg
www.wallacecompany.com/cnc_lathe/HNC/00004-1a.jpg

The second and third picture show a perf board with a differential chip that is used to convert the TTL signals from the quadrature sensor to RS422 differential. These chips are easy to find and wire up.
www.digikey.com/product-search/en/integr...vers/2556324?k=rs422
www.jameco.com/webapp/wcs/stores/servlet...eText=rs-422%20rs422

U S Digital has chips, boards and complete encoders.
www.usdigital.com/products/interfaces/encoder/cable-drivers

en.wikipedia.org/wiki/Differential_signaling

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Kirk Wallace
www.wallacecompany.com/machine_shop/

Great idea, Thanks a lot!

Kirk - Andy

Do you know by any chance if there is a list within LinuxCNC showing servo motors suppliers with reasonable good price and quality. The reasons I’m using Lenze servo drives is due to the included Ethernet port, Basic language programming, Modbus TCP communications and the $450.00 USD price.

I have not been able to find a similar proposal anywhere else. I use servo drives mostly in standalone applications and now I’m planning to used them with LinuxCNC.

Thanks for the knowledge.

I would shy away from smart controller/drivers for LinuxCNC which has motion control logic built in. There are plenty of people using these kinds of controllers, but it seems that either the controller or LinuxCNC need to be compromised to get it to work. Usually the controller's PID needs to be tuned and sorted out separately, then LinuxCNC's PID needs to be tuned or reconfigured to live with the controller. LinuxCNC integrates better with dumb drivers or amplifiers that use simple velocity or torque commands, with all of the tuning going on and openly available in LinuxCNC. Mesa and Pico Systems have FPGA interfaces and amplifiers that work well with LinuxCNC and motors with common encoders and Hall sensors. Keling www.kelinginc.net/DCBrushlessMotor.html seems to get mentioned for motors.
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Kirk
www.wallacecompany.com/machine_shop/