Poseidon2
– Family manual
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Sensor hysteresis
The
Hysteresis
setting defines a tolerance band for alarm alerts. This feature prevents multiple
alarm alerts if the reading oscillates around the specified threshold. See the graph for an
explanation.
Without a hysteresis of 5°C, the alarm raised at
point 8
would end at
point 9
. With the hysteresis
function, the alarm continues until the temperature rises above the tolerance band (
point 10
), that is,
5°C + (-15°C) = -10°C.
Hysteresis = 5°C:
The unit sends
3 e-mails (SMS)
Alarm at points
0..4, 8..10, 12 and beyond
No hysteresis (0°C):
The unit sends 8 e-mail (SMS) messages Alarm active in
points
0..1, 2..3, 8..9, 12..13, 14 and beyond