text: <s>[INST] PowerFlex 4 drive failures Just since the first of the year, nine drives have failed; all with the code F122. These drives have been running since 2007 with no problems. Aside from drive fatigue (just worn out), what might be causing these failures? [/INST] F122 is usually related to component failure on the control board. I suspect that the fault code was chosen because 50 Celsius = 122 Fahrenheit. :robotvery-happy: I've seen this in drives that were mounted without sufficient clearance for airflow, or put into an unvented enclosure in direct summer sunshine. Above about 120F you're going to have premature component failure after a few weeks or months of operation. High levels of electrical noise can also damage control board components. Make sure the two PE connections are properly connected to the input ground and the motor ground. RA Knowledgebase article 46564 addresses some of the reasons for component damage that leads to this failure code. \\n </s>