Hi
If you want SNP capacity can be affected using Set up Matrix. It´s mainly used in SNP optimizer.
Please find below the link explaining the detail procedure.
http://help.sap.com/saphelp_ewm70/helpdata/en/47/fca2fd9fc4384be10000000a42189b/content.htm
Please let us know if the respective information is useful to you.
Thanks
Amol