The art of hysteresis adjustment

[Anonymous user]

Hello,

We had a bit of an issue over the weekend - our pagers were spammed fairly heavily by a sensative temperature probe. We would receive an alert when the probe hit 73 degrees farenheit - and then a subsequent clear, and then an alert, and then a clear, etc, etc. 106 times in 8 minutes.
Is it the hysteresis setting that would resolve this? Setting the hysteresis to 2 degrees variance? (it's currently set to 0)

Any help would be most appreciated.

Thanks!

Drew

[Erasmus_apc]

Having the hysteresis set to 0 degrees is the issue. The alarm is triggering and since there is no "delta" or difference required for it to clear, it just clears and re-triggers over and over. As you have asked, a 2 deg. hysteresis should cut down on your alarms. The size of the hysteresis setting is somewhat up to your own knowledge of the room/rack environment and your tolerance for alarms. Some customers are fine with a very low setting, others use 5 or 6 degrees.

[Anonymous user]

Great - thanks Erasmus

[Cap1_apc · Accepted solution]

Just an additional tip -

Make sure you do not set hysteresis too high, or else you can run into a situation where it isn't feasible to actually clear an alarm. It all really depends on your high thresholds and the sensitivity that you wish to be alerted on.