I am new to message boards, and my Mori mill. We had the machine operational, but setting the last year has not been agreeable to it. I get an error code (393-TG error)(Z). I did some digging in the manual and found that the Z axis board has the OC LED lit up (which is just above the TG LED) on the board. I was successful in getting it to reset once, and the Z axis servo powered up , moved it up and down a couple of times, then it kicked out again with the TG error code 393 Z again. I need some guidance on this, also wondered what these LED's are telling me, there are several in a vertical array;
-fuse
-OL
-OV
-OC
-TG

Reset only worked once, but momentarily cleared the lite.
MAN, have I got alot to learn. Also , This machine has a Yasnac controller on it. Thanks, Dan

TAC Generator error is generated from either the encoder or the drive. There is a jumper on the drive that you can set to bypass the tac generator error if you wish to temporarily run however I would not recommend it for Z-axis. You may be able to swap the top boards on the drive with another axis drive. But you must check that they are the same part numbers as well as set any jumpers on the boards. Since the Z axis has a brake and gravity will make the head drop like a rock I would recommend putting a block of wood under the head and move it down to just above it as a precaution. I have never had any problems before but it only takes a few minutes just incase. This will help you determine if its the top board on the drive or an encoder problem.

Hope this helps

OC mean over current if the drive will shut down may be the control think there is no TG feed back. Need the drive type and call Yaskawa 1-800-927-5292 for help Thanks