I have a model where failures can occur, but also preventive maintenance. This preventive maintenance should repair the machine in such a way, that it is as good as new, e.g. the machines failure should start over. Model works fine, I thought. I schedule preventive maintenance using a threshold: if time passed since last repair (failure or maintenance) exceeds this threshold, preventive maintenance should be scheduled. When this happens, I deactivate the emergency failure profile, and later I activate it again. However, it seems this doesn't do the trick. Because in my output, when I set this threshold very low, many preventive maintenance actions occur, which is correct. However, the number of emergency repairs does not change in comparison with other values for the threshold. This should change, since when preventive maintenance is scheduled so often, the machine should never actually fail, so no emergency failures should happen, or less.
I also tried ?.eraseFailureEvents, does not work too, or I put it in the wrong place (tried many options), but then also the failure events of the preventive failure profile are deleted and so on..
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Also tried to completely delete the failure, and later on create a new failure. Does not work. I can't imagine why this does not work, because completely creating a new failure profile, should "reset" it. However, when having the lowest threshold possible, so preventive maintenance happens all the time (e.g. every second), there still is emergency failures??? While the emergency failure is created after every preventive maintenance action, with a very ''big'' interval compared to the threshold, so it would not be possible to have emergency failures. I don't understand.
if you deactivate a failure profile, the scheduled failure-event (EventController) will be deleayed. If you re-activate the failure-profile, a new failure event is scheduled.
If you want less failures after preventive Maitenance, you should change the availability of the emergency failures (e.g. in steps, deactivate failure profile, change availability, re-activate).
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Yes, but that is not what I mean. I also don't work with availability, but with interval and duration.
Example: It can be that the last failure occured at 15 minutes simtime, and the interval is 30 minutes. Then the next failure will happen at 45 minutes simtime. However, when at time, say 42, minutes, a maintenance happens, the machine is as good as new. So the next failure should not occur at 45 anymore, but at 74 minutes. (42 + 30). So everytime maintenance happens, I delete the failure profile, and if the maintenance is over, I create it again, so the machine should be as good as new.
I am trying to model this process too, but I am having trouble in whether to change the parameter of the distribution in the failure interval. Can you give me some advice？