Fault 7510 in ABB ACS800 drive

Fault 7510 in ABB ACS800 drive indicates a COMM MODULE fault. This means loss of cyclic communication between the drive and the fieldbus master (PLC).

Why is this happening?

Before you start swapping out expensive parts, let’s look at the usual suspects:

• Cable Issues: A loose connector, a crimped fiber optic cable, or electromagnetic interference (EMI) disrupting the signal.

• Module Seat: The fieldbus adapter might not be seated properly in its slot on the RMIO board.

• Timeouts: The "Comm Loss Timeout" setting in the drive is too aggressive for the network traffic.

• PLC State: The Master PLC might be in 'Stop' mode or the network itself has crashed. 

Troubleshooting Checklist

Step	Action	What to look for
1	Check the LEDs	Look at the Fieldbus module. If the "Link" light is off or "Host" is red, the module isn't talking to the drive.
2	Verify Parameter 30.18	Check the COMM FAULT FUNC. If it’s set to "FAULT," the drive trips. You can change this to "CONSTANT SP 15" for testing to see if the drive keeps running.
3	Check Parameter 30.19	This is the COMM FAULT TIME. If it’s set to 0.1s, it might be too fast. Try increasing it to 1.0s to see if the fault clears.
4	Inspect Wiring	Ensure the termination resistors are "ON" at the ends of the physical segment and "OFF" everywhere else.