User manual

Publication CNET-UM001C-EN-P - November 2005
8-2 Troubleshoot Your ControlNet Communication Modules
1756-CN2 and 1756-CN2R
ControlNet Communication
Modules
This figure shows the status indicators used on the 1756-CN2 and 1756-CN2R
modules.
Figure 8.1 1756-CN2 and 1756-CN2R Status Indicators
Module Status Indicator and Module Status Display
Diagnostic Information
This table describes the Module Status Indicator LED and Module Status
Display diagnostic information.
Table 8.1 1756-CN2 and 1756-CN2R Module Status Indicator and Display
Module Status Display
Module Status Indicator
Network Channel
Status Indicators
1756-CN2 1756-CN2R
Channel B BNC Connector
Channel A BNC Connector
If the OK
Indicator Is
With This
Module Status
Display
It Means Take This Action
Off None Module not communicating due to a power
supply fault or internal fault.
1. Check the power supply.
2. Check the cable connectors.
3. Make sure the module is firmly seated
in the chassis.
4. If the indicator remains off, replace the
module.