This setting sets the delay before considering a power interruption as a power outage event. You will not get a notification about power outage if it less that this delay. NOTE! With the value set to zero you will probably detect even small flickers. However, we can’t guarantee this, because it will depend on your environment but in most cases it will detect about 200ms interruptions. If you don’t want to detect such short interruptions we would recommend that you keep this setting to 1 or 2 seconds. We allow this to be change up to 90 seconds while actually it is designed to either detect flickers or regular outages - no more than that. So, realistic values you should use are either around zero (to detect flickers with possible multiple alarms) or 1 (for regular outages).