Negative inventory and on-hand problems
Negative on-hand means Epicor believes more has been taken out of a bin than was ever put in. It’s usually a symptom: a receipt not yet entered, labor reported before material was moved, or backflush pulling from the wrong bin. This page covers the controls Epicor gives you and the cases they don’t cover.
The Part Class setting
Section titled “The Part Class setting”Each Part Class has a Negative Qty Action that applies when a transaction would take a part’s on-hand below zero:
| Setting | Effect |
|---|---|
| None | The transaction goes through silently |
| Warn | A warning appears, but the user can continue |
| Stop | The transaction is blocked |
It applies to interactive transactions such as Issue Material, Mass Issue to Mfg and quantity adjustments.
What the setting doesn’t catch
Section titled “What the setting doesn’t catch”Backflush is exempt. Backflushed material is issued as a side effect of labor reporting, and there’s no user to show a warning to, so the Part Class rule isn’t applied. Kanban Receipts issue all their component materials by backflush, so they can drive on-hand negative even when the class is set to Stop.
Blocking these transactions wouldn’t help anyway: the labor or receipt has already happened on the floor. The better question is why the backflush went negative. Nearly always it’s one of:
- The wrong bin. Backflush typically takes material from the backflush warehouse and bin of the resource or resource group on the material’s related operation, or from the part’s primary warehouse and bin if none is set. If the stock actually lives elsewhere, the backflush bin goes negative while the real bin stays full. Point the resource’s Backflush Warehouse/Backflush Bin (or the part’s primary bin) at where the material really is.
- Timing. The receipt or transfer that should have filled the bin hasn’t been entered yet.
- Unrecorded substitutions or scrap. The floor used something other than what the method says.
If you do need automation, trace a Kanban receipt to find the method that performs the backflush and use a BPM to pick a bin with enough stock before the issue is written. See Find the method a screen calls.
Finding negative bins
Section titled “Finding negative bins”A BAQ on PartBin with OnhandQty < 0, joined to Part for the description and class, gives a daily
exception list. Review it alongside recent PartTran rows for the part to see which transaction took it
below zero.
PartLot shows on hand with nothing in any bin
Section titled “PartLot shows on hand with nothing in any bin”Symptom: a lot is still flagged as having stock (PartLot.OnHand is checked) but PartBin has no
quantity for that lot, so the lot keeps appearing in lot searches.
Cause: the flag is normally cleared automatically when the last quantity leaves the lot. Occasionally a transaction leaves it set.
Fix: it can’t be cleared from the UI. Ask Epicor Support for a data fix to recalculate or clear
PartLot.OnHand for the affected lots.