Product specifications

Troubleshooting
9-23
SIMATIC 545/555/575 System Manual
9.9 Checking PROFIBUS-DP Cable Installation
Verify the PROFIBUS-DP system cable installation using the following
guidelines:
• Inspect system terminations (too many, not enough or incorrect
placement.) See Section 6.3 for proper placement of termination
connectors.
• Check for a short in the cable with an ohmmeter.
• Check for an open circuit in the cable between the point of
measurement and one or both of the termination resistors with an
ohmmeter.
Line-to-shield resistance that is generating errors may be caused by one of
the following situations.
• One of the 9-pin connectors is connected to an RBC or CPU.
• Cable line wires are shorted to the shield.