setup time of a server

[sander]

Hello,
I have a problem with the set up time of a server. In the model there are 2 types of products who arrives and when the current and previous producs are different, there will be a setup time of 900. The problem is that the server knows when they arrive so it is not always 900, because he can start earlier if he is idle. This problem can be solved by putting 900 extra to the cycle time of the server if the product after the current product differs. Is it possible to put this in a model?

[BartC]

Hello Sander,

Have you modeled the setup time using the standard strategies of the server? Because if you use option 5: "Cur-Prev Label: if the value of the label named LabelName of the current and previous atom are different, the setuptime is 10", the server will check if a product is different from the previous when that product enters the server and then will use the specified setup time. So it will not start with the setup before a product enters the server.

Hope this will help you.

Regards,

Bart

[sander]

Thanks, but I already knew that. The problem is that there will not always be a setup time, because the server knows when producs arrive.
With option 5: "Cur-Prev Label, it will indeed not start with the setup before a product enters the server. But I want in my model that the server will start with the setup before a products enters the server, because he knows when they arrive.

[BartC]

Hello Sander,

I now understand what you want to do. A way to achieve this is by setting a label on the server when a product leaves, containing the time at the moment of exiting. Then also set a similar label on a product at the moment the server should know that it is coming (in my example model attached to this post I set this label on the exit trigger of the source, before the product enters the conveyor). Then make your setup time dependable on these labels, it should look something like this (also see the example model):

Code: Select all

if(
  <>(t-Getsetupcode(label([Product],first(c)),0),ddb([t-oldsetupcode],c)),
  Max(
    (900 - (Time - Max(label([ProductExitTime], c), label([ServerKnowsTime], first(c))))),
    0
  ),
  0
)

The last step is to use an initialize atom to reset the label on the server every time you reset the model. Hope this will do the trick.

Regards,

Bart

[sander]

Thanks a lot! The model works without label([ServerKnowsTime], first(c)).