Any reason to not use Constrained Materials at all?

  • 11 February 2023
  • 3 replies

Userlevel 2

Is there any good reason to not use constrained materials at all?

We turned that on for purchased parts last August after not using it at all for over 3 years since Go Live. We did it in conjunction with starting to use Global Scheduling on a recurring scheduled process. (After several months of that, I was told to turn it off, my objections never being heard.)

With the constrained materials turned on, now our unfirmed jobs created by MRP would get rescheduled out according to availability/lead time of purchased parts, which to me makes logical sense that you would want that to happen—especially since our Sales department puts basically every order arbitrarily inside of lead time. And when we were using Global Scheduling, this would happen with our firmed jobs; now we just have a ever-growing bunch of firmed jobs locked into past dates that we can't finish today due to material not being available. 

But now it's being suggested to me that maybe we need to also turn off Constrained Materials entirely, because Purchasing is now just ordering everything at lead time and doesn't know what they should be expediting (even though I've shown them how to use Production Planner Workbench to view material shortages), so those in power think the solution is turning off Constrained Materials so Buyers know what POs should be at lead time and which ones they should order short of lead time. This would put us right back into where basically everything now becomes an expedite and very little is actually ordered at lead time. Even though it's more likely to arrive at lead time, whether ordered there or not.

(Oh, and we infinite schedule without anyone actually ever adjusting the schedule, other than a random job here and there.)

So, my question to all of you great Epicor users, is do you have any more ammo you can give me to argue for keeping it? Or am I incorrect here and maybe Constrained Materials is causing us more problems than not using it?

3 replies

Userlevel 3

I have found that in most instances flagging a material as constrained causes more bad than good results, as long as you maintain the various planning factors that are available within the part record (such as min/max, non-stock, days of supply, lead time/supplier price list lead time, planning time fence etc.) gives better results

As per the help:
The Constrained Materials functionality uses this logic to calculate its results.
If Material Lead Time > Required By Date on the operation, then schedule the operation.

Userlevel 4

Buyers have many tools for manipulating and expediting POs and other sourcing tricks.  We’ve found it’s more effective to run with constrained materials disabled, and to provide enhanced “stock out risk”  reporting tools, to give them a better sourcing system.

We use constrained materials.  And we keep our lead times up to date. We have a few resources that are not heavily scheduled. If our material has a 3 day lead time. We don’t want epicor to schedule that operation before the material can feasibly be here. Using constrained materials helps us ensure operations aren’t scheduled before feasibly possible.