Encoder/feedback unit fg n tg?

Just sketching out a wiring diagram and I happened to look at my old notes and my feedback units,
Yaskawa TFUE-25ZD7 and 30ZD7 have two connections, labeled FG and TG, that I have no idea
what they are?
All I can find online is people flogging them.

FG is usually = Frame Ground, TG = T? Ground ?
Could be the logic ground?
Al.

Wonder if it is tacho generator?

Tach Ground maybe?
What is the rest of the notations?
Al.

I was looking at a sketch of the plug pinout, when I saw tg and fg, seems
there is actually a TG+ and TG-, I would say gotta be a tach, but I am rarely ever right;-)
Attachment 258566

Quote:

---

Originally Posted by integerspin

Wonder if it is tacho generator?

---

Looks like you were right, Tach Generator, strange though, if it is part of an encoder it would be a digital tach, not a DC version, unless it is separately wired, if DC tach, they are rarely used now on modern drives.
Al.