Rockwell Automation 9307 FactoryTalk EnergyMetrix - Manual (Page 228)

FactoryTalk EnergyMetrix Software
228
Use the MPR for Cost Allocation
True ‘cost allocation’ across groups and meters can be performed by using MPR scripts by
calling the CostAllocate method of the Group or Meter objects. The two most common
types of cost allocation include:
 Calculating an overall energy rate for a site and applying it to groups or meters within
the site.
 Finding site peak demand and allocating cost to groups or meters based on their
contribution to that peak demand.
Setting-up Rate Schedules for Cost Allocation
Before cost allocation can be performed from MPR script code you must set up at least
two rate schedules.
Billing Report Rate Schedule Requirements
 Set up a billing report rate schedule that reflects the energy supplier rate tariff. The
rate schedule should calculate the total cost for energy for the report period.
 Set up at least one run-time parameter to be used to pass the cost allocation rate to the
Cost Allocation rate schedule. Other run-time parameters can be set up to pass other
variables, for example, the peak demand UTC timestamp string.
 In the billing report rate schedule, add a line item which calculates the cost allocation
rate and assigns it to the run time parameter. This line item is typically of the form
Cost Allocation Rate = (Total Energy Cost) / (Energy Measurement Units) with the
usual protections against division by zero. To suppress display of the line item on a
standard billing report, you can set the line item Visibility to False.
Cost Allocation Rate Schedule Requirements
 Set up a cost allocation rate schedule that applies the cost allocation rate to the energy
usage of each selected group and/or meter
 Set up a run-time parameter with the identical name as the cost allocation rate run-
time parameter in the billing rate schedule
The CostAllocate method runs a billing report, passes a
parameter to another rate schedule, and then runs the second
rate schedule to calculate an output value. Repeating this
process for a number of report line items can load down the
server and cause long report run times. It is suggested to set up
the cost allocation rate schedule to return a rate variable, which
may then be buffered in a declared variable and used to
calculate the report line items.