Let's assume that event Y occurs in a device if its temperature has deviated from its baseline for 10 or more seconds.
In other words, these 10 seconds represent a time period. And I would need to say:
This is the value of the time period for which the temperature ____ in order for Y to happen.
A) has to be deviated
B) has been deviated
C) deviates
I am not sure whether the perfect should be used or if choice A is OK.
I can't tell if the temperature change is good or bad. When you say a temperature deviates from the baseline that implies that the change is bad (maybe heating due to over current condition?). If the process and change is a good thing then use more positive words: exceed, surpass, or rise above all provide a positive view.
If the temperature deviates from the baseline for more than 10 seconds then the over current alarm will activate.
A sentence like this will warn the user of the result of the temperature change. There is a negative feeling associated with "deviates".
After the temperature has exceeded the baseline for more than 10 seconds then the process will start.
You could use a sentence like this to describe a good result that the user is attempting to create.
First time periods cannot be described as having a value. Time periods have a duration. Actions resulting from a trigger condition being met are best described as occurring instead of happening.
Ten seconds is the duration of the time period for which the temperature must deviate in order for Y to occur.
This sentence is most like your original goal, but does not sound natural and I cannot find a good context it would fit in. It is quite understandable though.
After the temperature has deviated for ten seconds Y will occur.
This sentence would best fit into a description of steps in a process.
If the temperature deviates from baseline for more than ten seconds Y will occur.
This sentence puts the emphasis on informing the operator of what will happen if the temperature changes.
