A01487 alarm in siemens 6RA80 DC Drive indicate that the Option slot component not inserted. This means the topology comparison has detected an option slot component missing in the actual topology with respect to the target topology.

1. Insert the components involved at the right connection (correct the actual topology).
2. Adapt the project/parameterization in the commissioning software (correct the target topology).
3. Check the 24 V supply voltage.
4. Check DRIVE-CLiQ cables for interruption and contact problems.
5. Check that the component is working properly.