text: <s>[INST] frequent failure of IGBTon PF700s frame 5 & 6 Summary: frequent failure of IGBT resulting to multiple downtime Hi, We are experiencing frequent (10x different controller) IGBT failure on powerflex700s frame 5 & 6 (20DR096A0ENNANASE & 20DR248A0ENNANASE). Supplier recommended to install voltage conditioner and yet failure continues, resulting to frequent shutdown of our paper machine (happens on paper dryer section). Loads are at 60% only. Thank you in advance. [/INST] https://rockwellautomation.custhelp.com/app/answers/detail/a_id/17254 The article above is somewhat flawed - it should have a schematic diagram image with it but does not. Still, it points to one possible scenario - the snubber resistors have failed. You've given us very little information with which to assist you. When the drives failed, did you replace the entire drive, or just the portion that failed? What sort of voltage conditioner did you install? Do you have an output contactor between the drive and the motor? Does the enclosure containing the drive have sufficient cooling? Much as one would like to point a finger at the drive as being a bad design, the PF700S is one of the best Rockwell has ever offered. There are MANY of these drives operating today. It's most likely that there is something about your particular application causing the failures, especially on two different frame sizes. The more information you can give us, the more likely we'll be able to help you solve the problem. \\n </s>