User Manual Owner's manual

238 Rockwell Automation Publication 280E-UM001B-EN-P - July 2012
Chapter 10 Troubleshooting
Media Counter
Errors or Collisions
The media counters screen displays the number of physical layer errors or collisions. The screen below
indicates where to check for errors encountered. Error levels are displayed depending on what caused
the error. For example, an Alignment Error is displayed in the Alignment Error field.
Figure 89 - Media Counter Screen
On a DLR network, it is not uncommon to see low levels of media counter errors. For example, if the
network breaks, a low level of media counter errors appear. With a low level of media counter errors, the
value typically does not continuously increase and often clears.
A high level of media counter errors typically continues to increase and does not clear. For example,
there is a mismatch of speed between two linked nodes, a high level of media counter errors appears,
steadily increasing and not clearing.
To access the RSLinx screen above, browse the network, right-click on the device, select Module
Properties and click the Port Diagnostics tab.
Some example solutions include:
• Check for a mismatch of speed and/or duplex
between two linked nodes.
• Verify that all cables on the network are
securely connected to each device.
• Check for electromagnetic noise on the
network. If you find it, eliminate it or use a
protective shield in that location.
Table 46 - Troubleshoot DLR or Linear Network
Issue Description Solution