MRP - Force part to always produce X days sooner

We are having one hell of a time with MRP giving us usable suggestions. We’ve paid Epicor consultants, we’ve paid third party consultants and neither have made a positive impact on the results. With that said, I typically don’t deal with MRP so forgive me in advance if I ask any ignorant questions.

In this instance, we have a part that we would like to have FINISHED 10 (work) days before the due date.

Here you can see that it suggest the job 2 days before it is due - presumably because of the pieces/hour.

What is the proper way to do this? Extra points for showing your work.

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Could you not set a receive time of 10 days? I’m still not incredibly sure of all MRP does as it’s so complex, but that’d be my guess.


Our MRP guru is out for the holiday still but IIRC, believe the “Production
Prep Buffer” should be the field you’re looking for.


Maybe that’s the ticket - my planner tells me they tried Receive Time at one point and it “screwed everything up”. :smiley:

Thank you both for the suggestions.

I think it is the Receive Time as well…


Ditto on Receive Time, although it changed behavior between Epicor 9 and Epicor 10. In Epicor 9, MRP would actually back the JobHead.DueDate up 10 days if you had receive time set to 10 on the part. In Epicor 10/10.1, the JobHead.DueDate will not be backed up at all, but the JobAsmbl.DueDate and JobOper.DueDate fields will all be backed up 10 days, so essentially it will have you completing the final operation 10 days before the “due” date (the date you need it done for shipping).


We’ve tried it and now we’re even more confused. We added 10 days Receive Time (first it appears to be calendar days and not work days).

In the production planner workbench it almost seems correct. It’s off by a day or two but probably because it cant suggest a job earlier than todays date - which is where it did. Original date was 25th, revised date 18th


Timephase BEFORE:

Timephase AFTER:

What are we seeing here?

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What version of Epicor are we on again? If you open that job suggestion up in Job Entry, do you see a Start Date and Final Opr Date on the summary tab? What do those say?

As far as the calendar vs. work days, do you have a Production Calendar setup that is off Saturday/Sunday? Example:

Then you would apply that prod calendar to all of your resource groups (and/or resources?) that would affect that job (or maybe just all of them).

Is this a purchased, manufactured, or kit part?

Is there a revision and a MOM?

Version 10.1.400

This is a mfg part with a rev and a mom.

I am pretty sure we have the production calendar setup

Add a 10 day move time to your last operation resource.

Are you trying to get the assy 10 days before your shipdate or trying to get your need by of an order to be 10 days prior.

I put in an order with a NBD of 4/30/2017, so that my SBD is 4/20/217 and my job can be in inventory by 4/10/2017.

This is a single op part. We are make to stock.

We would like this part to be ready to ship 10 days prior to the actual demand.

When we need to add fat its more operational than by part… we use move time and queue time. Try adding another operation that has a prod std of .00001 and either use queue time or move time. We have an outside service operation that adds 48hrs to a particular subassembly, it is there purely so the start time and end time of the subassembly is realistic. We generally use queue time as occasional we have found the system can ignore the move time if its the last operation.

Depending on what the materials for the job are, I would use the manual “Cumulative Time” and “This Level Time” to add the extra days in.

If you always have the material to produce this available immediately, I would enter 10 days in “This Level Time”.

If you have a lead time on the materials, I would put 10 days in “Cumulative Time”.

We also use queue time on a zero dollar resource group “Shipping” with a final operation “Shipping” to give us padding for items that must have extra time for packing.


So why has it moved the due date up?

We don’t use receive time for adding padding for the packing. We use queue time on the resource group. Using this, it does not move the due date up. See below :slight_smile:

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Leadtime Fields.

Do these fields need some special setting to be factored into the MRP time calculation? We have set them manually on some test parts and as far as we can see they are ignored by the MRP

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Sorry for the delayed response, last week I was straight out.

I did a very poor job on my prior response, I did not get far enough into the weeds. Let me do a better job.

To add a random 10 days to a MOM, I would do the following. First, make sure that the “Include in Manufacturing Lead Time Calculation” option is enabled on the Site record. Underneath that, I would at a minimum enable “Kit Time”, “Lead Time”, and “Receive Time”. If you use rough cut parameters, you can also enable that one.

Now, with these options enabled, you can use them to add time at the part level to certain steps. So, to have the material available 10 days before you want to ship, add 10 to “Kit Time”. This only works on manufactured parts and would tell the system that it takes 10 days to kit for shipment (even thought it doesn’t).

“Lead Time” and “Receive Time” only work on purchased parts. So, if you wanted to ship to a vendor early (if subcontract) or wanted to pad the time it takes for a vendor to send you items, you would add time into “Lead Time” and the system would tell you to cut the PO earlier. If you wanted to pad time after the parts/items are received, you would add time into “Receive Time”.

Alternatively, if you use the “Manufacturing Lead Time Calculation” under Engineering/Gen Ops, after you run it, you could add 10 days to what the system calculated in the Cumulative Time/This Level Time and enter it into the manual Cumulative Time/This Level Time.

Please let me know if you have any questions as I am not the best explainer.


Super response, thanks so much. Does all the same apply at the part class level?

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