1734

Common Causes

• Program error, e.g. commanding pickoff chuck open (M249) while the pickoff spindle is running (M13 SB=1000)
• Operation error in MDI/manual commanding chuck open or spindle start in the wrong state
• Pickoff spindle at-still signal not present when the chuck command is issued
• Pickoff chuck close signal dropping out while the pickoff spindle is rotating

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 1 = Pickoff chuck open command given while the pickoff spindle is rotating; code 2 = Chuck open/close command issued without the pickoff-spindle-at-still signal; code 3 = Chuck open command issued while a pickoff spindle rotation command is effective; code 4 = Pickoff spindle rotation command issued while the pickoff chuck is open; code 5 = Chuck open/close command issued during spindle/pickoff synchronous control by the flat turning function; code 6 = Pickoff chuck close signal turned OFF while the pickoff spindle is rotating
2. 2Read the alarm code: 1 = chuck open commanded while the pickoff spindle is rotating; 2 = chuck open/close commanded without the pickoff-spindle-at-still signal; 3 = chuck open commanded while a pickoff spindle rotation command is effective; 4 = pickoff spindle rotation commanded while the chuck is open; 5 = chuck command issued during spindle/pickoff synchronous control by the flat turning function; 6 = chuck close signal turned OFF during pickoff spindle rotation.
3. 3Correct the program sequence: stop the pickoff spindle completely and confirm it is at a still before issuing the pickoff chuck open command, and close the chuck before commanding pickoff spindle rotation.
4. 4For code 5, do not issue pickoff chuck open/close commands while flat turning synchronous control between the spindle and pickoff spindle is active; cancel the synchronous mode first.
5. 5If the sequence is correct, check the pickoff spindle at-still signal and the pickoff chuck open/close confirmation signals at the I/O monitor for a faulty switch, loose connector or wiring fault.
6. 6For code 6, investigate why the chuck close signal dropped during rotation — check the chuck proximity switch, its wiring and the chuck actuation hydraulics/pneumatics for pressure loss.
7. 7If signals check out and the alarm returns, record the alarm number, code and object and contact Okuma service.