Downtime & uptime occurring same time?

[rajankur6494]

[ FlexSim 23.1.3 ]

Hi Team,

I am applying the downtime and uptime to my equipment using variable distribution Weibull (for up time) and lognormal (for downtime). But I have observed few instances where downtime and uptime are trigged at the exact same time which is not possible in reality.

How this is possible?

Thank you!

[JordanLJohnson · Accepted solution]

If either the uptime or downtime expression can produce a value of zero or less, then the down/uptime would occur at the same time. If an event is scheduled in the past (such as bringing an item down 2 seconds ago) then it just happens at the current time and a message appears in the system console. For this message, the system console does not open automatically. If you open the system console and run your model, watch for any messages that mention an "event time in the past".

[jason_lightfootVL7B4]

Hi @Ankur A3, was Jordan Johnson's answer helpful? If so, please click the "Accept" button at the bottom of their answer. Or if you still have questions, add a comment and we'll continue the conversation.

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[rajankur6494]

Hi @Jordan Johnson,

To have quick workaround to avoid 0 time, I am using Math.max(0.1, distribution) currently.

Would you like to suggest anything else?

Thank you!

[JordanLJohnson]

That is a good workaround. The other option is to reconsider your choice of distribution. If you are using a distribution for a time and the distribution allows negative values, then there is a high likelihood that the distribution isn't a fair representation of the process.