Rockwell Automation FactoryTalk Metrics User Guide - Manual (Page 106)

Chapter 3 Collecting Performance Data
Item Description
MOPCTimestampOf() Uses a single data point as a parameter to return the millisecond
component of the OPCTimestampOf() function. This value is an
integer between 0 and 999 milliseconds.
Tips:
• The Transaction Control Manager will correctly evaluate the
time as it was received from the OPC or FactoryTalk Live Data
server. The FactoryTalk Transaction Manager will substitute the
TimeStampOf() or MTimeStampOf() functions for the
OPCTimeStampOf() or MOPCTimeStampOf() functions.
• Any OPC time is returned to the Transaction Control Manager
service as an UTC-formatted time. If you specify the local
format, then the time is converted based on the local time of
the Transaction Control Manager service, not the local time on
the OPC or FactoryTalk Live Data server.
TransTimestamp() Returns a timestamp value that indicates when the transaction
occurred. This value is accurate to the nearest second.
MTransTimestamp() Returns the millisecond component of the TransTimestamp()
function. This value is an integer between 0 and 999 milliseconds.
An expression can contain a range of values which it can use to
calculate an average of the previous 10 transaction values ( avg (
datapoint [0:9]). This functionality also works to calculate the
minimum (min) or maximum (max) value of a data point over
several transactions. Note that the transaction must be run to reflect
changes in the historical values. The results, however, do not need to
be stored. Using the Store on Every N Transactions option, you can
collect the data needed for an average, but not store the data to the
database. If a transaction executes every second, but only stores its
data every 60 times and there is an avg ( datapoint [0:59]), the value
that is stored once a minute is the average of the values collected
every second.
Data Point Functions
106 Rockwell Automation Publication PLTMT-UM001M-EN-P-June 2014