BECKHOFF CX2020 - Manual (Page 41)

Error handling and diagnostics
Error code argument
The number of pulses indicates the position of the last Bus Terminal before the fault. Passive Bus Terminals,
such as a power feed terminal, are not included in the count.
In the case of some errors, rectification does not cause the power supply to leave the blink sequence. The
power supply can only be restarted by switching its supply voltage off and on again.
5.1.3 LEDs of the power supply unit (CX2100­0xx4) in E­bus mode
After switching on, the power supply immediately checks the connected Bus Terminal configuration. If K­bus
terminals are detected, the error­free bootup is signaled by the red “I/O ERR LED” going out. If the “I/O ERR”
LED blinks, an error in the area of the terminals is indicated. The error code can be determined from the
frequency and number of blinks. This permits rapid rectification of the error.
Display LED Meaning
Us 24 V Power supply for the CPU module. The LED lights
green if the power supply is correct.
Up 24V Power supply for terminal bus. The LED lights green if
the power supply is correct.
L/A off E­bus not connected
on E­bus connected / no data traffic
flashing E­bus connected / data traffic on the E­bus.
CX2020, CX2030, CX2040 41 Version 1.2