[Cause]
The servo errors of the master and slave axes differ greatly. This alarm occurs when the absolute value of $DUAL_DRIVE[i].$SYNC_ER[n] exceeds $DUAL_DRIVE[i].$SYNC_ER_TOL[n]. (i: group number, j: master axis number, n: dual-drive pair number)
[Countermeasure]
Check the mechanical unit for problems. Alternatively, readjust the parameters related to synchronization error compensation to appropriate values.