State Transition with a time delay

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Frazer Watson
Frazer Watson on 8 Jun 2015
Commented: Julia on 9 Jun 2015
I have a state transition which needs to be triggered when a condition is met for a fixed period of time.
In the example below, the response I would like is for the transition from the on to the off state to occur when the input is > 0 continuously for 5 seconds. If, during the 5 seconds input becomes <= 0 the state should remain on and the timer should reset. i.e. if input is > 0 again, it will wait for 5 seconds before transitioning to off.
The state machine below will transition to off instantly if input becomes > 0 after it has been in the on state for > 5 seconds.
Any help with resolving this problem is appreciated

Answers (1)

Julia
Julia on 8 Jun 2015
Hi,
you have to combine your two conditions with '&&'. That should solve your problem.
  2 Comments
Frazer Watson
Frazer Watson on 8 Jun 2015
Thanks Julia.
I've tried the following for the on to off transition:
[after(5,sec)&& input>0]
although I'm still seeing the same problem. I believe that the 'after' timer is only reset on the transition into the state. this means that the 5 seconds begins as soon as the on state is entered rather starting when input is > 0.
I can fix my problem by adding the 'StartTimer' state as shown below which resets the timer when input is <=0. Doing this on my actual system would create other problems as I execute logic using the 'during:' command whilst in the on state and these would be distributed by as the state switches to StartTimer and back.
Julia
Julia on 9 Jun 2015
Here is another solution. However, I did not use the after() command.

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