A service engineer was dispatched who could confirm the reported sporadic reboots upon logfile review and trace it back to the pcb that controls the therapy functions; the two microprocessors onboard this pcb obviously had a communication interrupt which could not be removed by other means than rebooting.The reboot would incorporate a short-term outage of therapy functions for a maximum of 15 seconds and is accompanied by an alarm before the therapy is resumed with the last valid settings.The reported observations confirm that.The board was replaced as a precautionary measure, the device passed all consecutive tests and was returned to use.The number of similar cases, related to the same root cause, is within the expected range of the respective risk assessment and thus accepted.
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