text: <s>[INST] motion fault My system is L43 and K6K*2, program is ok. But when I power up the PLC and motion at the same time , the CPU happan a fault every time.  Type 11 : motion fault Code 13 : SERCOS comm fault detected. Axis : drviver1I can clear the fault by turning the key from PROM to RUN .but how can I sovle it . [/INST] Power up your PLC and then wait for the Contact Enable contact to close on the K6K, which is the drives indication that it is ready for 230/460VAC power. This will give your Sercos ring time to power up. Also make sure that before you do a MSO in your program that the drives bus is up and they are ready. There are several status bits that you can look at to ensure that the drive is ready to be enabled. \\n </s>