Operating instructions and typical troubleshooting
 | Notes on CU1521-0020 The CU1521-0020 operates in FreeRun mode. As the CU1521-0020 has no outputs, no watchdog is required. |
Symptom | Probable cause | Test/measure |
|---|---|---|
No link on the SFP port | Wrong SFP type, wrong wavelength, wrong remote station or fiber problem | Check SFP data sheet, wavelength, fiber type, connector, attenuation and Rx Signal Detected. |
Link available, but no data | Encoding or operating mode does not match | Check rotary switch position, EtherCAT/Ethernet mode and from HW02 CoE 0x80n0:11. |
DDM warning/alarm | Temperature, supply, Tx/Rx power or bias outside limit value | Check DDM Ext. status and DDM values; evaluate optical and thermal budget. |
EtherCAT diagnostic data implausible | Process data invalid if continuing EtherCAT connection is disconnected | wcState and configure a separate SyncManager for the SFP device. |
BiDi route does not work | Two identical instead of complementary BiDi-SFPs used | Compare Tx/Rx wavelengths of both sides and insert complementary pair. |
SFP gets too warm | SFP power loss or ambient temperature too high | Use industrial SFP, check temperature diagram and select SFP with lower power consumption if necessary. |