purchase requisition or planned order generated for external procurement

Dear all,

there is an issue can you please advise the solution.

A lot of materials maintained as external purchase(F), after MRP running, if possible to have some materials get planned order, and some materials get purchase requisition?

I tried to set the different MRP group and assign it for different materials, it seems system will takes MRP running's parameters override material master's MRP group setup, the setting like bellows.

MRP group

Z001 - generate planned order

Z002 - generate purchase requisition.

MRP running, like MD02

generate purchase requisition, 1-purchase req. 3-planned order.

is there any other setting I missed? thanks so much.

Regards,

Jun