HYSTERESIS

[BillP]

Hi everyone,

Good day. I was just wondering, could someone please help me with this. I can't seem to understand its purpose. It's in the web browsing of the SRT5KRMXLI UPS. What is the purpose of HYSTERESIS in the Temperature Threshold of the unit. I attached the screenshot for you to see. Does it have something to do with heat dissipation? Please enlighten me, your response is appreciated. Thanks!

[Anonymous user]

Hysteresis is the property by which a system (or sensor) "wants" to stay in the same state as it was. It basically allows conditions around a system to change to some extent without causing the system in question to respond as it normally would. A heating or cooling system's thermostat, for example, employs hysteresis  so that the room temperature can change slightly without the attached heating or cooling system being continually triggered over minute changes in temperature.

In the case of your SRT5KRMXLI UPS, enabling the Hysteresis  setting would allow the temperature setting to "swing" a little more than it normally would before an alarm is triggered to indicate a problem or warning. You can set how much "swing" over the upper or lower limits is allowed.

[voidstar_apc]

The way I like to think about it is that without hysteresis, if the threshold is 50 degrees and the temperature is at 50 degrees, the recorded temperature will move a little above and below 50 degrees repeatedly triggering and clearing the temperature alarm as it drifts despite the temperature not actually changing much. That's a nuisance. Instead with hysteresis we have two thresholds: one that triggers the alarm, and another one (offset by the hysteresis amount) that clears the alarm. The temperature can drift all it wants between these two thresholds without causing nuisance alarm activity.

[BillP]

Thanks William. 

[BillP · Accepted solution]

Thanks Voidstar.

[BarcodeMaker]

Hysteresis  control a cooling or heating element at the appropriate threshold.

[TradeLabelSoftware]

Hysteresis is a property of the behavior of magnetic materials. The hysteresis pattern is a common pattern.