F34887 — VSM DRIVE-CLiQ (CU): Component fault

The CU raises F34887 when the Voltage Sensing Module (VSM) connected over DRIVE-CLiQ reports a fault on itself. The message is generated by the CU on behalf of the component — the manual's title therefore reads "VSM DRIVE-CLiQ (CU): Component fault". What the VSM actually detected is coded as a fault cause in the message value (decoded below); the possible causes range from a telegram header error to errors in the telegram buffer memory and timing problems. The manual explicitly notes that faulty hardware cannot be excluded, so the message must be taken as a possible hardware failure of the module, its wiring or its connection.

• A fault has been detected on the involved DRIVE-CLiQ component — the Voltage Sensing Module (VSM).
• Faulty hardware cannot be excluded, i.e. the module itself may be defective.

1. Check the DRIVE-CLiQ wiring: look for an interrupted cable and for faulty contacts.
2. Check the electrical cabinet design and the cable routing for EMC compliance.
3. If required, use another DRIVE-CLiQ socket for the module (p9904).
4. Replace the component involved.

The message value carries two items — component number and fault cause — and the drive codes them together in one value, readable in r0949/r2124: 0000yyxx hex, where yy = component number and xx = error cause. The fault causes the manual prints:

• 32 (= 20 hex): Error in the telegram header.
• 35 (= 23 hex): Receive error: The telegram buffer memory contains an error.
• 66 (= 42 hex): Send error: The telegram buffer memory contains an error.
• 67 (= 43 hex): Send error: The telegram buffer memory contains an error.
• 96 (= 60 hex): Response received too late during runtime measurement.
• 97 (= 61 hex): Time taken to exchange characteristic data too long.

• r0949 (fault value): read out here to identify the affected VSM (component number yy) and the reported fault cause (xx), coded as 0000yyxx hex.
• r2124 (alarm value): named alongside r0949 in the manual's note on the message value; it carries the same 0000yyxx hex coding.
• p9904 (Topology comparison acknowledge differences / Topo_compare ackn): the parameter the manual names for using another DRIVE-CLiQ socket — after moving the module, the resulting topology difference is acknowledged with it.

The fault does not clear by itself: work through the checks above first, then acknowledge the fault and restart the drive. Depending on the drive object involved, the converter switches the infeed off when the fault occurs or lets the drive keep running — in either case the message has to be acknowledged before a clean restart. Before replacing the VSM, note the fault cause from the message value (r0949): it identifies the component number and the detected error cause.