Diagnostic LEDs
Display  | LED  | Meaning  | 
|---|---|---|
PWR  | Power supply Bootloader is started and runs without errors (the colors red and yellow light up for one second).  | |
TC  | TwinCAT status LEDs  | |
HDD  | Read/Write CFast card   | |
FB1  | Status LED1 for fieldbus (function is described in the fieldbus interface)  | |
FB2  | Status LED2 for fieldbus (function is described in the fieldbus interface)  |