The log file analysis revealed that during the case in question the device detected an internal communication error onboard a pcb that controls the communication between user interface, gas mixer and ventilator.The workstation initiated an emergency shutdown of automatic ventilation and posted corresponding alarms.Monitoring and manual ventilation remain possible in this state.The general issue is known from earlier occurrences of the same phenomenon.Intensive evaluation of the provided information and testing of concerned materials did not result in any finding.The fact that the involved pcb is used in another functional unit of the entire device without showing similar symptoms makes a design problem rather unlikely.A reasonable explanation would be emc disturbances beyond the immunity barriers of the workstation which is compliant to iec 60601-1-2.Therefore, it is recommended that the conditions at the user facility should be checked to prevent from emc disturbance.The number of similar cases, related to the same phenomenon, is within the expected range of the respective risk assessment and thus accepted.
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