Master Data question - Resource Master

Question

Hi,
Got some master data related questions on Resource master. I am kind of relatively new to APO and trying to understand master data fields and functionalities. Can someone please explain me in layman terms with a small easily understandable example,
1)     What is the difference between time continous capacity and bucket capacity?
2)     What and where do we use u201Cexternal capcityu201D? I read somewhere that if we check box the external capacity, then APO uses capapity from R/3. What difference does it make if capacity used from R/3 or bring it over to APO and use it from APO? When u check box the u201Cexternal capcityu201D you are already bringing the resource to APO. So what is the use of using the capacity from r/3?
3)     A Multi activity resource has a capacity of 8 hrs per day. For example a resource has 5 lathes and u can carry 5 different activities/operations at the same time on this resource. So every lathe has 8 hrs of capacity, that means the overall capcity is 5*8 = 40 hrs???? and where are we specifiying number of lathes u201C5u201D in the resource master?
4)     What is the advantage of deriving bucket capacity from time continous, than directly defining bucket capacity?
Thanks
Appreciate your help..

Answer 1

SCM,
I will today work on your question 1.  As time permits, if Sri Mathur cannot respond, I will then attack the another question later.
1) what I am trying to understand here is..bucket capacity is 1 day minimum. that means 24 hours of capacity????? if yes, then time continuous capacity can be equal to bucket capacity if no breaks. if breaks are there then it is less than bucket capacity?
If one operation takes 2 hrs then that means, 1 SNP bucket capacity can hold 12 such operations??? Really confused.
Buckets can have any amount of capacity.  For instance, if you define a capacity as a Daily bucket, you can further define it to have less than 24 hours of capacity.  The difference is that the system manages this capacity as a single chunk.  
Lets say I have a time-continuous capacity, which starts at 8:00 and ends at 16:00.  It has 8 hours of capacity available. If I am consuming capacity with, say, a planned order operation, the system will check whether the capacity is available, and when it is available.  So, the first planned order op that begins capacity consumption at 8:00 AM and consumes one hour of capacity will normally use the 8:00A-9:00A block of capacity.  If I am capacity leveling and dispatching, then no other order will be allowed to consume capacity during this time period (8A-9A).
Now let us consider the same resource, but configured as a single day bucket.  I still have 8 hours of capacity.  However, when I create a planned order to consume capacity, it only checks whether I have enough available left in the entire bucket.  The same first planned op order mentioned above, could be scheduled for 8A-9A, and would also consume 1 hour of capacity.  This cap consumption is not 'from 8A to 9A', but is '1 hour out of the bucket of 8 available'.  The next production order could also be scheduled for 8A-9A, and pass a capacity availability check, because there are 7 hours still available in the bucket.  8 1-hour planned order ops could be scheduled from 8A-9A, and still pass the cap check.
Time continuous cap consumption becomes very important if you are doing detailed sequencing of your orders, as is normally done in PP/DS.  SNP, which is usually less detailed, is more likely to use bucketed caps (with many exceptions!!).
Rgds,
DB49