Alarms from zones & hysteresis
I stumbled upon this issue when one of the temperature measurements is bouncing between configured zones and sending excessive amounts of push notifications. See the attached photo (copied from web) which quite clearly describes the case. Usually, such issue has been solved by setting a hysteresis range, for example in case of a temperature measurement it could be from 0°C to 1°C. When T goes down to 0°C, alert is summoned, but in order to clear the alert, T must rise to 1°C or above. I'm sure everyone is aware of this solution.
The question is, how have you solved this, is there perhaps another plugin for triggering notifications or have you sorted it out with Node-RED? Or am I using zones wrong?
5 Replies
there's no out of the box solution for this, but this is something that i've thought about
i think there at least two related issues here, hysteresis in value domain and "how long the value needs to be in the zone" in time domain
Something to include in the planning of alerting specs that @Matti Airas started in another thread perhaps
Related, but not the same. Alerts can exist without zones, for example mob is probably not inititated by zones
So if a crew member tries to climb back on board and fails to do so several times within a short period of time, we should do something to suppress the false positive alerts
😆