Hello,
I have a KRC2 running v5.6.12 of the KRC software. It is connected to a KR 16 robot and has worked reliably in the past. Recently I moved the installation to a new location (after not running the system for about 6 months) and after setting everything back up have run into an issue where the robot runs for about 15 to 60 seconds and then stops with error #1136 "Ackn. heat sink temperature PM1". I have good cooling in the case (checked while running with the door open) and have not encountered this issue before. After encountering the error I shut down the robot, disconnected power, waited 5 minutes so circuits could safely discharge, and then checked around in the KRC2 looking for hot spots but found none. In particular I checked the KPS (KPS-600/20-ESC) for any visible issues. I disconnected all cables and removed it from the KRC2 so I could check the heatsink. There was very minimal dust buildup which I cleaned, but after installing it again there was no change in behavior.
An important detail about the behavior is that the error is encountered even without moving the robot. Merely enabling the drives (for example, by holding the deadman switch in T1) is enough for the error to occur (takes same amount of time - between 15 and 60s).
Suspecting a bad temperature sensor I checked the values using DSE-RDW. This showed the heat sink temperature hovering near 70 C before enabling the drives. Then it rapidly rises past 80 C when the drives are enabled and the ESC disables them again. So I am guessing that the temperature sensor is okay and there may actually be rapid localized heating in the power supply for some unknown reason.
Unfortunately I do not have another KPS available to swap in and see if that resolves the issue. Anyone have suggestions for further troubleshooting steps?