Calender Issue while generating MRP

when i try to generated MRP for a sales order for an item which has single level BOM it is working fine. Problem: If i generate MRP for BOM in BOM im getting the calender error saying that calender are not available before 03/01/00 for Work Center w0001(which i have created) when i can do MRP calculation for a single item, why can’t i do it for a low-level item. Rama

Hi, system calculating work center schedule backward and your order required work to be started before 03/01/00. You should create calendar for work center w0001 for year 2000. Go to Workcenter card w1000 → select Planning → Calendar → Functions → Calculate → On Options Tab select Start and End Dates → OK.

Thaks for u r reply, i have calculated calender for the period 2000-2002, but still it shows me that there is no calender before 2000, in fact my order date is in 2002. Rama

Hi Rama As Erik states this is probabaly a calendar issue, set up a work centre calendar for the period 1998-2000 as well. The BOM will backward schedule and if you have BOM’s within BOM’s it does not take two many lead times and a complicated BOM for the system to tell you that to get something ion stock today you should have raised a purchase order two years ago! Alternatively schedule the requirement date as 2004 and run MRP. Steve

Ooopps Sorry Valentin, mistaking you for Erik and everything [;)] Steve

Hi Guys! I have a serious problem: I`m at the customer site and they will go live TOMORROW morning and I need your help. I have a calendar problem in Navision 3.6. If generate MRP for BOM in BOM im getting the calender error saying that calendar are not available before 01/01/97 for Work Center w0001(which i have created. I dont understand why I should have calendar entries before 1997 even if I dont have orders before that date. Any clue?? Thanks.

Hi, I see this behaviour once I made a mistake and the BOMS where calling themselves recursively.

Have you guys setup any constraints on the Work center. Check the times in the Routing and the Lot size on the Item card. Do you have any Routing Link Codes. Check for the Capacity Unit of measures, type.

Also check the unit of measure code on the work centre is specified - I think this causes the calendar message. Good luck [:D]

Have you calculated Low-level code? MRP can said you bad results if low-level code isn’t calculated. Best regards from bcn.

In 3.10 there was a problem with the Rounding precission on the Work center card. In case you have some things below 1 then you need change it back to 1.