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TASX Bit 9 -- Velocity Error Limit Exceeded

This bit activates when the maximum velocity limit value (user-defined via the SMVER command) is reached or exceeded. The SMVER default is 0 (not monitored). The instantaneous velocity error value - queried with the TVE command - is compared with the SMVER value every 2ms. At the instant that TVE exceeds SMVER, the drive disables the bridge and this TASX bit is set to 1.

Common causes for the activation of this error bit is either:

1) an unrealistic maximum velocity error limit (SMVER), or

2) poor motor tuning for the given application.

This bit can also activate as the result of a runaway condition. This error bit should not activate when the drive is in Torque mode.


To clear the active bit, issue a DRIVE0, then a DRIVE1 command to allow the GV/GT to re-energize. To prevent the bit from activating,

1) check that DMVLIM or SMVER have not been set lower than the commanded velocity setpoint,

2) check the motorís tuning parameters.