I am having a problem with my spindle not coming on. It will not come on when executed through the program or midi. I am not getting any faults on the drive the "?" light is coming on when I attempt to turn the spindle on. I found what I believe to be the pressure switch for the chuck and jumped it out but this did not resolve the problem. Any ideas? :confused:

Depending on what spindle drive you have, there is either LED's on the sp drive or a 4 digit 7 segment display that will display the status. What is the "?" light mean, or is this a 'mystery' light, is it the spindle start light on the operator panel?
If the drive looks like it has been activated but the spindle does'nt turn, Check the brushes if it is a DC spindle.
Al.

Ok, the pressure switch for the chuck is opening and closing as it should and the door switches are jumped out. I checked the brushes and they are good. Wierd. Anytime I try to start the spindle the red "?" light on the control panel comes on and the spindle will not even attempt to turn.
The red "?" light is on the on the operator panel and I have been lead to believe that it only lights up during an alarm state.

OK, I would assume you are not getting any system alarms on the Fanuc screen, which would indicate it is a control problem hang up, Does the spindle have gear change functions? If so is the gear change done automatically or do you have to issue an M code? Is the spindle in gear, if so some have limit switches to confirm the fact.
Al

I appreciate the feedback..........The Machine is a Takisawa TC-2 Fanuc system 0. The rotary encoder works when turned by hand (registers RPM's) The hydraulic pressure is 30 psi. The machine has been in this shop for some time and was operational but sat idle with power off for a week. I can not locate any additional chucking position switches, the pressure switch for the chuck is working as it should. With the exception of the chuck, everything seems to be working fine. The red "?" light only comes on when I try to turn the chuck on. I don't have any faults on any of the drives, boards or screen. The spindle is in gear and switches gears when prompted.

With the exception of the chuck, everything seems to be working fine. The red "?" light only comes on when I try to turn the chuck on.
OK things have changed, originally it was when you tried to turn the spindle on, but of course these two are usually related. Does this happen when you issue a M3 and/or chuck close, is the chuck close by M code or foot pedal?
Al.

I continue to brain fart, sorry. The chuck works fine, attempting to turn on the spindle creats the fault state

This problem could be solved very quickly if the PMC ladder diagrams were available, and also a bonus if you have the 0 version that can display the ladder on the screen. The status of all the functions can be seen, because whoever wrote the machine control, obviously indicated by using the light that certain conditions were not met, Unfortunatley they were probabally too lazy to write a operator message into the fault indication.
BTW does the light just apply to the Spindle?
The light shows as a physical output in the ladder and any condition that caused the light to be on could be seen right away, a switch or sensor etc. The laddder shows up similar to a wiring diagram on the screen, in the form of normally open/normally closed contacts with coil outputs, any contact that is 'made' is highlighted, this way it is very efficient to finding elusive problems, but one that many seldon use.
I gather you have no electrical documentation on this lathe?
Al.

Nope, no electrical information to reference. I'm at the mercy of what people send me right now. I have had no response from Takisawa. I am searching the internet as we speak trying to locate something that will be of some help to me which is why I like this web site so much.

The spindle just started turning with no apparent corrective action taken! I can't explain it. The last thing I did was to check the wiring in the foot pedal because I couldn't get it to work (it was working earlier). I repaired a short in the cable and now everything works?!?!?!?!? Trying to make sense of this.............

By foot pedal, I assume that is the chuck FP? It depends how the logic was written, as in some the pedal has to be released after closing the chuck, if defective wiring showed that that although the chuck was closed the pedal appeared to be still operated, it could have showed a fault.
Hopefully you will find some documentation.
Al.

Yes, the chuck foot pedal. Sincerest thanks for the feedback. Great site! I will continue to search for any and all documentation I can get for this equipment. :wee: