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Hi
What is the downside of setting negative days to something high - say 365 days - similar to my time fence?
All advice welcome
CEL1967
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It will distract your planning engine nothing else,
take an example : year 2011
you have some contract purchase orders based on your forcasting or may be somthing else for month of april 2011
you have sales order which is to be deliverd in month of february,
if your negative days are to high, system will never generate planned purchase order it will give you action or future massage for so and already generated po for some else requirement,
and negative days are generally used for short term like 2-max 10 days
if u have a sales order to be deliverd on date of 1 feb. and i already have 1 po which is to be deliverd to me on date of 8th of feb...due to some reasones like delivery cost is high or Item is 1 time order like that you can use this facility.
you can have positive days like 365 days no problem
It really depends upon the ordering metrics but in my belief these are the same as the positive days, except that the impact can be greater because of the reduction of potential lead time, however to answer your question the impact would be that rather than a movement message you would get a new order, which manywant anyway, leaving the originally later committed order where it is, but it really depends upon the item and industry in my experieince,
Hardick is correct. With a high negative days, master planning will generate an 'Action Advance' message - with a low negative days, you will get a new planned order. For purchased items it seems to make sense to set the negative days equal to the coverage time fence (and monitor the Action Advance messages). But for production orders, your users may prefer to rely on planned orders and in that case, set the negative days low.
We are using both negative and positive 365 as we were gettiing planned orders when we should have gotten exception messages to expedite or defer as required. We want to net out to zero, not have on hand excess inventory. We just started using AX over a month ago and we are still struggling with viewing action messages. Shouldn't we be able to see ALL of our expedites and defers for PO's? I have a hard time believing I am the 'PERFECT" Buyer with no exception messages. I believe we have our settings incorrect and am having a difficult time finding what they SHOULD be. Any input is greatly appreciated.
Hi,
We have struggled as well with the positive and negative days. The entire coverage dimension logic seems strange, expecially in our make to order environment.
On our purchased parts, we are using the lead time as the negative days. We do not get planned purchase orders in front of already placed purchase orders. However, this approach does not put the action message on the purchased part, but on the next part up the BOM until it reaches the top.
For the positive days, we are using our company's policy of 120 days - which means you are allowing your inventory to remain positive for 120 days. Any demand outside of the 120 days will generate a purchase order.
It really is contigent upon how long your lead times are. We also created different coverage groups based upon lead time, part type, etc.
Since going live in July, MRP has been our biggest obstacle to get smoothed out, so lots of empayth for you.
I can see in principle that there is no point in having Negative Days different from the Lead Time - provided the Action Messages are acted upon!
From my testing, I find that even zero negative days is OK providing you have "Dynamic Negative Days" parameter ticked on in Master Planning Parameters. Dynamic Negative Days when used takes account of Lead Time of the product.
It strikes me that using Dynamic Negative Days is an efficient way of configuring Dynamics Ax. Appreciate any feedback please.
I’ve been in many implementations, especially with regards to Master planning there are quite many requirements customers request and compare to other products (SAP). Based on the way Master planning is developed in AX and the logic behind. AX master planning is rule based. Based on the requirement (Make to order scenario) I always recommend, Keep coverage time fence days and Positive days same. Keep Negative days 0. In this case you will not miss any requirement. It works very well.
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