Hysteresis Settings help please
13 June, 2012 - 11:20
What should my hysteresis setting be in the CurrentCost and Pachube settings to get a full 'real-time' view?
On one of my boxes I'm experimenting with clamps but get period of the same value being uploaded. I'd like to understand if this is hysteresis or a box problem?
Hysteresis is implemented within HAH as the deviation between recent past values. http://en.wikipedia.org/wiki/Hysteresis
If you want triggering on all value changes, keep it at 0.00. In other words say the temp 60 secs ago was 20.1 degrees and a new value comes in at 20.2 degrees, this is a value difference (deviation of more that 0.00) so event gets triggered. In above scenario if hysteresis was set at 0.2 then the temp would have to move to 20.4 or 19.8 to get an event, i.e more than 0.2 either side.
As a general aside, I have not looked if there is any rounding done within the HAH code, but expect so, especially on 1 wire, so this in itself can affect how the hysteresis works (as sampling precision canl act a little like hysteresis itself).
Summary: Set to 0.00 for the most 'chatty' for each service.
I am sure someone else will correct above if I understand it wrongly.
--andy