Batch Delay

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JPersico
Junior Member
Posts: 4
Joined: Thu Oct 09, 2003 3:50 pm

Batch Delay

Post by JPersico »

I have a batch delay that releases requirements once the stock accumulating it reaches a value of 1 (100 % complete). The batch delay is the approval rate that drains the stock. Why is the release triggered early, so that 1 flows out of the stock, even though the stock has not reached a value of 1 yet, so it goes negative? The batch size is 1, with no initial backlog.

Since my model is arrayed by requirement, this problem gets progressively worse with each element. By the sixth element, the flow is triggered when the stock is only at a value of 0.65
Wilson
Administrator
Posts: 51
Joined: Thu Mar 06, 2003 5:05 am

batch delay

Post by Wilson »

The batch delay should release the trigger amount, lagged by the specified delay, whenever the trigger level is reached buy accumulating the inflow.

I have attached a little demo model which hopefully demonstrates this. In the top batch delay flow there is an ever present inflow, in the lower part of the diagram the inflow stops once the trigger level has been surpassed. Graphing the "accumulated 1" variable demonstrates the effect of using the batch delay

It's difficult to work out why this is not working as you hoped in your case, perhaps you could post the equations or a mini version of the model.
Attachments
my batch model.mdl
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