Fault Code: FU121
Fault Description: Servo ON Command Invalid

Cause:

• When the internal enable function is active, the external servo enable signal (S-ON) is simultaneously triggered.

Solution:

1. Check if auxiliary functions P0D-02, P0D-03, or P0D-12 are configured for internal enable.

2. At the same time, DI function 1 (FunIN. 1: S-ON, servo enable signal) is valid. Set the DI function 1 (including hardware DI and virtual DI) signal to invalid.

Note: This fault occurs when both internal and external servo enable signals are active simultaneously, causing a command conflict.