Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 User Manual, Firmware rev. 3.0 or LATER - Manual (Page 83)

Publication 1404-UM001F-EN-P - November 2009 83
Communication Chapter 4
Timestamp format. The power monitor expresses timestamps in an
array of four data table elements: Year, Month/Day, Hour/Minute,
Second/ Hundredth of a second
Each timestamp parameter (except the Year) is a combination of its
first and second element. For instance, the Month is the parameter
value divided by 100 and the remainder is the Day.
Example: 1230 = December 30th. The timestamp data type may be
integer or floating-point and depends on the data table.
Other Common Data Table Elements
The power monitor uses several common data table elements in a
number of data tables. These include:
•
Password: A valid password must be written to change
configuration settings or issue commands. For selecting records
to read back, you may write either a valid password or a value
of -1. Default 0000, range 0000…9999.
•
Record identifier: The power monitor assigns event log records,
oscillography and transient captures and other items unique
identification numbers. These numbers typically begin at 0,
increment by 1 each time a new record is created, and roll over
to 0 once they reach their maximum value, typically 32,767. The
data client may use the record identifier to associate records in
different data tables or to ensure that subsequent reads contain
fresh data.
•
DeviceNet unique write identifier: The DeviceNet
communication port on Powermonitor 3000 models, with
optional DeviceNet communicaitons, discards duplicate identical
messages. For that reason, read-back selection tables include a
DeviceNet unique write identifier element. The data client
changes (usually, increments) the value of this element each
time it writes an otherwise identical message.
Writing Data to Data Tables
The power monitor contains a number of writeable data tables. These
tables have read/write access, so a client may read their current
content or write new content.