If I am maintaining Lot size dependent information such as set time, Interoperation time, Processing time in work scheduling view in material master and also Total in-house production time in MRP view under scheduling tab, what will effect on the system?
Means how will the system behave in this scenario?
In house production time in MRP2 view, specifies the time in workdays needed to produce the material in-house. In-house production time is independent of the order quantity. The system requires the in-house production time to determine the planned dates for planned orders in materials planning.
You can define work scheduling times in the material master
record in one of two ways:
-Either you enter the in-house production time. If required,
you can get the system to update this value from the routing.
-Or you enter the setup, teardown, processing, and interoperation
times. If you maintain these values, the system determines the in-house
production time on the basis of lot size.
SAP PP Tips by : Brajesh
What is the basic fundamental of "Independent lot size" and "Dependent lot size" in work scheduling view of a material master. I am jumbling a lot between this two to understand the basic requirement of my client.
Second thing is that you are
saying that - You can define work scheduling times in the material master
record in one of two ways:
-Either you enter the in-house
production time. If required, you can get the system to update this value
from the routing.
-Or you enter the setup, teardown,
processing, and interoperation times.
But how the system update this
first option.
I mean to say , is there any
setting in configuration so that the system will update workscheduling
time values from the routings?
You need scheduling data for 2 types of orders, planned orders and production orders.
And you can have the scheduling
data in 3 ways:
1. Lot size independent in-house
production time, in material master, MRP2 view. ex: if in house production
time is 2 days, it will schedule the order for 2 days, and it doesn't matter
if the order size is 1 or 1000, they are both produced in 2 days. (I never
met any case that fits this situation)
2. Lot size dependent in-house production time, in material master, Workscheduling view. ex: if you have 5 day setup time, and 1 day production time for lot size of 10, then your order will be scheduled according to the order size. if your order is for 10, then your total production time will be 5 day + 1 day x 10 / 10, which is 6 days. If your order is for 100, then your total production time will be 5 day + 1 day x 100 / 10, which is 15 days. 5 day setup time will not change when the order quantity changes, because you make the setup once at the beginning of the production, and use the same setup during whole production.
3. Lot size dependent in-house production time, in routing. The same calculation of above will be used for this.
So, which of these data is used
for the 2 order types?
For the planned orders, for default,
system uses the times in number 2 above. If that data is not entered, system
will use the time in number 1 above. If you want the system to use the
routing data, then you should use lead-time scheduling parameter in MRP
run, then system will use data in number 3 above.
(The idea behind this is, MRP run always takes long time, and if you want it to use routing data, that will also increase this run time. Therefore, you can use routing but take results after long MRP run time, or you can use approximate times but take the results after short MRP run. This was very crucial before, because at those times hardware technology was not enough to process too much data in short time, when MRP run was taking days and days. But now is not that crucial, that's my personal opinion. As I said before, you can use routing data but take results after long MRP run time, or you can use approximate times but take the results after short MRP run, however, there's one other way which is a combination of these two: You can use the system to update the data in number 2 using the data in number 3, which is called the update of material master from routing. In that case, the approximate production times in material master will be as close as possible to the actual production times. In that case, not only MRP run will not take long time, but also we will get much better results.)
For the production orders, always the routing data is used for scheduling.
Now, I am cleared that what is
independent and dependent lot size. but still there is one confusion in
my mind that where did we mentioned this lot size i.e 10,100 as per your
example in case 2.
Secondly, I didnt understand
your second last sentence (i.e.the approximate production times in material
master will be as close as possible to the actual production times). Can
you please clear me this sentence with suitable example.
You enter the lot size on the Work scheduling view of material master, for the lot size dependent times, for my example you enter 10 as lot size.
And the approximation is like this: In the material master, you enter the production times as DAYS, but in the routing you can use MINUTES, even seconds. Therefore the most detailed and accurate production times can be entered in routing, in material master you can enter only days, which will be the approximate value.
If your routing is, for lot size of 10, setup time is 3 hours and production time is 50 minutes, when you update the material master from routing, system will write 3/24 days for the setup time, and 50/1440 minutes for the production time, because it has to convert it to days.
But still I dont understand that
where I have to mentioned that lot size 10 or 100?
And second thing is that, If
I have to use routing data for planned order what should I have to do?
Shall I have to mentioned lead time scheduling in MD02?
You enter lot size in material master, on workscheduling view.
and yes, you have to mention on md02 screen that you want lead-time scheduling.
You mean to say I have to enter that 10 or 100 in base quantity of work scheduling view of material master?
Yes.
SAP PP Tips by : Osman Karslioglu
