SSI Encoder Wiring

[kitchy]

Has anybody ever seen an SSI encoder interface that only uses 2 wires. I beleive the standard is 4 wire, 2-clock and 2-data. I am trying to retro fit a servo drive. The drive was custom made to change the buffered encoder out port to an SSI port. This SSI port is connected to a PC controller and is used to close the position loop. I'm just confused as to why only 2 wires. This doesn't seem to comply with any standard that I am aware of.

 

[Clyde38]

Possibly RS422 (2 wire). See attached. .


[link

http://www.linkedin.com/in/clydehancock

]

[/url]