Applicable Systems
PanelView Plus 7
Symptoms
HMI screen shows 'Communication Lost' or red cross over PLC connection icon.
Possible Causes
- Ethernet cable disconnected or damaged between PanelView and PLC.
- PLC IP address changed or mismatched in RSLinx Enterprise configuration.
- Ethernet switch port disabled or spanning-tree blocking the port.
Troubleshooting Steps
- Step 1: Verify Ethernet cable integrity and reseat both ends.
Link LED illuminates on both NICs. - Step 2: Ping the PLC IP address from a laptop on the same subnet.
Ping replies consistently <2 ms with 0% loss. - Step 3: Open FactoryTalk View Studio, check RSLinx Enterprise shortcut target IP.
Target IP matches actual PLC IP and status shows 'Running'.
How to Reset
Restart the PanelView terminal and verify the PLC connection indicator turns green within 60 seconds.
Source: Allen-Bradley PanelView Plus 7 User Manual
Category: HMI