Okuma Alarm A-8648 – Tailstock Tool Mode Mismatch

Alarm A-8648 indicates that a cutting command was executed while the tailstock (tail spindle) tool mode did not match the required operating condition.

This alarm occurs when the control detects an inconsistency between the active machining command and the current tailstock tool mode setting. In other words, the machine attempted to perform a cutting operation while the tailstock was configured in an incompatible mode.

When this alarm appears:

• The tailstock mode does not correspond to the active machining program

• A cutting cycle was initiated under incorrect tailstock configuration

• The control blocks further operation to prevent mechanical damage

Possible causes include:

• Incorrect tailstock mode selection (manual vs. automatic)

• Wrong spindle/tool configuration parameter

• Program command not aligned with machine setup

• Mismatch between tool data and machine state

• PLC or interlock signal inconsistency

Recommended actions:

1. Verify the tailstock operating mode.

2. Check program commands related to tailstock/spindle.

3. Confirm tool and spindle configuration settings.

4. Reset the alarm and reinitialize machine state if necessary.

5. Review parameters related to tailstock control.

This alarm prevents improper cutting operations that could result in mechanical stress or damage to the tailstock or spindle assembly.