1367

Common Causes

• Workpiece mounted is shorter than required, so the quill over-travels before reaching the set thrust
• Tailstock positioned too far from the workpiece before the sizing/advance command
• Sizing command at position B issued while the tailstock was not at A position (code 9)
• Excessive torque from ball screw inertia or thrust outside the instructed tolerance (codes 6/7)

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 1 = Command torque was not reached before entering sizing position area 1 within the quill expand/shrink time; code 2 = Torque above the set thrust occurred when actual position moved to the + side of sizing position area 2; sizing was commanded from before the approach position; code 3 = Torque over the threshold occurred during tailstock movement within (T1+T2)*1.25+48 ms from the approach or movement start position; code 4 = Actual position is outside the sizing position area while the tailstock is in sizing position status; code 5 = Torque above the set thrust was generated after lowering; code 6 = Torque exceeded the limit for ball screw inertia; code 7 = Actual thrust is outside the tolerance of the commanded thrust; code 8 = Deviation between sizing position and actual position exceeded the allowable limit
2. 2Read the alarm code on screen to identify which thrust/position condition failed.
3. 3Check the mounted workpiece length against the required length; a short workpiece is the manual's stated cause — reposition the tailstock closer to the workpiece and retry.
4. 4Code 1: the quill did not build command torque before reaching sizing position area 1 within the quill expand/shrink time — move the tailstock body nearer the work so the quill contacts it within stroke.
5. 5Code 2 or 5: thrust above the set value was detected past sizing position area 2 or after lowering — verify the tailstock was commanded to the sizing position from beyond the approach position, not from too close in.
6. 6Code 9: confirm the tailstock is at A position before issuing the sizing command for position B.
7. 7Code 4, 8 or 10: check for mechanical slip or obstruction of the quill/ball screw so the actual position tracks the sizing position within the allowable limit.
8. 8If the alarm returns after repositioning and length checks, record the alarm number and code and contact Okuma service.