When i run MRP or maintain MRP Prod Orders the start and finish date falls apart by one day even if the order qty is very small. It should start and end on the same date
In work center the fields r
resource unit 1; basic cap per week 48hrs; per day 8hrs ;shifts=1
In routing prod rate =600/hr
if the mrp order qty <=23 pcs order starts and end on same date
if mrp order qty> 23 the start date is1 day ahead when i press <cont><shift><r>
the working hrs 00:00 upto 24:00 in BaaN
Prod rate is in hrs in Manuf Parameter.
If i increase resource unit or shift or no of hrs the capacity increases proportionately when MRP order is maintained.

Advice is requested
Thanks
Savit

Check the Work Center field Waiting Time. If you want the order to start and end at the same day, this field should be set to 0. It looks like it's 1.

Hi,
we have the same effect on our system and the waiting time in the work center is zero.
So it's not a problem of routing or capacity. The reason is the the production planning process within the MRP run. Production planning in Baan is based on percentage of the available capacity not on exact hours and minutes. The smallest planning unit is 1%.

Your daily capacity is 480 minutes. A production rate of 600 is equal to a runtime of 0,1. The total runtime for 23 pieces is 2,3 Minutes. 2,3 Minutes is equal to 0,479% of 480 Minutes. This amount is rounded to zero. So start and end date are on the same day. The same calculation with 24 pieces: 2,4 minutes = 0,5% of 480 Minutes are rounded to 1%.
If the required capacity of a production order is equal or greater than 1% of the daily capacity there is always a difference between start and end date of a production order. The difference is one day at minimum (depends on the company calendar).

Martin

Hi Martin

Yr logic seems to be perfectly ok
what could be done to bring the Mrp planning on the same day?
It should take orders on the same day (not 1% but upto the capacity defined).
If we go for lower levels 4 or 5(child) this one day adds to planning orders many days before it is required thus increasing the inventory.
2. is the prod rate defined in routing be per person per hr basis or is it total prod per hr(not cosidering no of persons)
3.what shall be done so that child item Prod begins at the same time as its parent(assume that sufficient safety stock is present)

Savit

Hi Savit,

the only way to get start and end date of mrp-orders on the same day is to define runtime as zero. Of course the disadvantage of this 'solution' is the total loss af capacity planning. Probably not the way you want to work!? What really happens in your shop floor with this orders? Does every operation starts on the same day? I suppose not.

I'm not quite sure where your problem is. Is it the problem of increasing stock? We noticed this problem when we started working with an ERP system for the first time. What we did is to reduce safety stock (even to zero) on every level in the hierarchy of operations and materials execpt on the lowest level. In other words: only the basic materials, normally purchased items, have a significant safety stock.
Safety stock is regarded as a fixed reservation of materials during the mrp run - just like a salesorder. That means it will not be taken in to account for the availability of material. This effect may lead to increasing stock.

Regards,

Martin