Generate alarm based on slope of cooling trend not set point 1

[GNIKOLI]

I would like to have Rockwell FactoryTalk produce an alarm as product temperature starts to reach its minimum temperature based on a cooling curve rather than a minimum temperature. For instance, as the slope of the cooling trend as averaged over a certain period of time reaches a particular value, Factory Talk will produce an alarm. I am not an engineer and I don't know ladder logic. All I have is a concept I think makes sense for our operation and I would like to know if it can be done. I do know my way around FactoryTalk a little, so if it was just a matter of doing something at HMI level rather than PLC level, I could probably follow instructions well enough. Can anyone point me in the right direction?

AB ControlLogix 1756 & Rockwell FactoryTalk View Site Edition (to be upgraded).

 

[danw2]

I use Honeywell's process controller that has a rate of change function block that generates a tagged 'alarm' output based on whether the input deviates from the rate of change conditions established in the function block. (details in linked file)

But that's on the controller end, not the HMI end.

I'd recommend you search the FactoryTalk documentation for a rate of change alarm. If it doesn't have it, I strongly suspect CLX has the equivalent function block which could be implemented on the hardware side. Or you could write your own code.