A01425 — Topology: Serial number different

A01425 is raised when the drive's topology comparison detects a difference between the actual topology and the target topology on one component: the serial number of the connected component is not the one expected. The message value names the affected component — %1 is the component number, %2 the component class — and %3 is the number of differences.

Although this is only an alarm, its effect is drastic: The drive system is no longer booted. In this state, the drive control (closed-loop) cannot be enabled.

• The topology comparison has detected a difference between the actual and the target topology in relation to one component: the serial number is different.

1. Read the alarm value in r2124 and interpret it hexadecimal in the form ddccbbaa: byte aa is the component number (%1), byte bb the component class (%2) — the component classes are described in F01375 — and byte cc the number of differences (%3).
2. Open "Topology --> Topology view" in the commissioning tool (commissioning software); where relevant it offers improved diagnostics capability, e.g. a setpoint/actual value comparison for the affected component.
3. Adapt the topologies: either change over the actual topology so that it matches the target topology, or download the target topology that matches the actual topology using the commissioning tool.
4. Acknowledge or deactivate the differences as byte cc requires: if cc = 1, acknowledge using p9904 or p9905; if cc > 1, acknowledge using p9905 and deactivate using p9906 or p9907/p9908.

• The drive stores the alarm value in r2124; it must be interpreted hexadecimal in the form ddccbbaa.
• dd = reserved.
• cc = number of differences (%3).
• bb = component class (%2).
• aa = component number (%1).

• r2124 — alarm value: read the hexadecimal value ddccbbaa here to identify the component (number and class) and the number of differences.
• p9904 — topology comparison acknowledge differences: use it to acknowledge the difference when exactly one difference is present (cc = 1).
• p9905 — device specialization: acknowledges the difference, both alone when cc = 1 and as the acknowledgement step when cc > 1.
• p9906 — topology comparison, comparison stage of all components: use it to deactivate the differences when more than one difference is present (cc > 1).
• p9907 — topology comparison, comparison stage of the component number: use it to deactivate the differences when cc > 1.
• p9908 — topology comparison, comparison stage of a component: use it to deactivate the differences when cc > 1.

The alarm is not removed by simply clearing it at the drive; the topology difference itself must be resolved and then acknowledged via the parameters: with one difference (byte cc = 1 in r2124) using p9904 or p9905; with more than one difference (cc > 1) using p9905, and deactivated with p9906 or p9907/p9908. As long as the alarm is present, the drive system is no longer booted and the closed-loop drive control cannot be enabled, so the drive only comes back once the topology matches and the difference has been acknowledged or deactivated.