A7478 alarm in siemens sinamics V90 drive indicates the EPOS Target position is greater than the software limit switch plus. This means a direct setpoint command is trying to send the axis past its positive software limit.
Cause: In the actual traversing operation, the target position is greater than the software limit switch plus.
Remedy:
- Correct the target position.
- Change software limit switch plus (CI: p2581).
