Supply and demand for co-products

Hi,

I have a situation where two mfg modes take place.

Process manufacturing followed by discrete manufacturing.

The discrete mfg pull on the co-product.

I run MPS/MRP in discrete mode that will generate messages for the Co-Products.

Then I run MRP in Process mode that is based on the Co-products messages and create messages for process WO based on the pacing item.

However when the process mode is ran, the messages of the co-products disappear all what I see is the process item WO.

in the pegging file I see only the pacing item as input to the process item.