Allen-Bradley · Logix and SLC PLC
This error indicates that the 1771 adapter is not available to communicate with the modules within the 1771 rack. This could imply a problem with the backplane communication or the adapter's internal state.
Click steps to track your progress.
Inspect the 1771 adapter for proper seating and secure connection within the 1771 rack backplane.
Verify the power supply voltage to the 1771 rack and the 1771 adapter, ensuring it meets the manufacturer's specified nominal voltage.
Check the diagnostic LEDs on the 1771 adapter for any error codes or abnormal status indications.
Inspect the 1771 backplane connectors and the module card edge connectors for signs of damage, dirt, or corrosion.