HPFB bus timeout

What does 18 mean?

No serial communication is occurring with the adjustable frequency drive’s communication option card (HPFB bus). This warning is active only when parameter 804 (Bus time interval function) is set to a value other than OFF. If set to 'Stop and trip', it will ramp down and trip into an alarm state.

• Disconnection or damage to the fieldbus cable (e.g., Profibus DP cable) connected to the HPFB option card.
• Incorrect Profibus address (P801) or baud rate (P802) configuration on the HPFB card or the Profibus master.
• Profibus master (PLC CPU or communication module) is not active, stopped, or not sending data frames.
• Faulty HPFB communication option card or its internal connection to the drive's main control board.
• Missing or incorrect termination resistor on the Profibus segment where the drive's HPFB card is located.

Click steps to track your progress.

1. 1

   Verify the Profibus cable connections to the HPFB option card and at the Profibus master. Ensure connectors are securely seated.

2. 2

   Check the HPFB card's parameters (P801 for Profibus address, P802 for baud rate) and ensure they match the Profibus master's configuration.

3. 3

   Confirm the Profibus master's status (PLC diagnostic buffer) to ensure it is active and attempting to communicate with the drive's address.

4. 4

   Inspect the HPFB option card for visible damage or improper seating within the drive's option slot. Re-seat the card if necessary.

5. 5

   Check for proper Profibus termination resistors at the beginning and end of the Profibus segment, ensuring they are correctly switched ON/OFF.

6. 6

   Using a Profibus diagnostic tool, analyze bus traffic and signal quality on the segment to identify communication errors or signal loss.