Encoder Wiring

If I should post this elsewhere please let me know and I will but on my encoder I have 5 wires coming from it that run into a bundle inside of another loom, ok. now at the other end though there are 6 wires coming out from it. I researched and am thinking it could be a drain wire. If it is a drain wire what purpose is it and where should I even run something like that too. I have attached a picture of my encoder wiring. See there are 5 wires going out but down the line on the other end there are 6 wires coming out. 

I would check if the drain wire connects to frame ground,
If so, I would leave it unconnected at the 7I97 end.

Note that these are single ended encoders so the 7I97 encoder jumpers
must be set for single ended (TTL) mode

Kylizer: Can you post a picture of the other end of the cable? The 6th wire may just be the shield drain for the encoder cable. In a typical installation, the shield drain only connects at one end. I would normally tie the shield drain to the encoder 0V or ground terminal on the board side but defer to PCW in this case as he designed these boards.

PCW: can you clarify your answer? I assume you are stating that if the 6th wire is connected to the motor frame then in that particular case it should not be connected to the 7I97 but that does not address the case where the 6th wire is the encoder cable shield drain and not connected to the motor frame.

RT

If the 6th wire is only connected to the encoder shield
(not motor/frame ground) I would connect it to encoder
ground at the 7I97, but I would verify what the 6th wire
_is_ connected to first.

Here is where it comes from encoder. Then to the bundle and then the other end of encoder harness 

Its not connected to the encoder so I would leave it unconnected
at the 7I97 end

Layout

Went and double checked and I indeed had it set to differential. Switched it over to and sure enough I got it to read out on the dro when I rotated the spindle. Thank you

PCW wrote:

Its not connected to the encoder so I would leave it unconnected
at the 7I97 end

PCW, I always understood that the shield ground should be connected at least at one end. That is the recommendation from most encoder manufacturers such as Dynapar: www.dynapar.com/knowledge/encoder_issues...ring_best_practices/

Kylizer's picture shows his encoder wiring follows that recommended practice. I have a similar situation (7i97, single ended encoder) and connected the shield to 0 V terminal. Is there a particular reason not to follow this practice with the 7i97?

RT