Rockwell Automation 1426 PowerMonitor 5000 Unit - Manual (Page 185)

Rockwell Automation Publication 1426-UM001F-EN-P - November 2013 185
Communication Chapter 9
Data Table Addressing
Data tables can be addressed in several ways.
Symbolic Addressing
Status and metering results data can be addressed by their tag names, similar to
the manner in which ControlLogix controller tags are addressed. Symbolic tag
addresses are displayed in the power monitor’s web page, and appear in an
RSLinx Classic software OPC topic set up for a PowerMonitor 5000 unit.
CIP Addressing
Addresses are of the form Object:Instance:Attribute. CIP addressing allows
reading and writing of an entire data table (assembly instance) rather than
individual elements. In CIP addressing, the energy metering results table is
Object Class 4 (Assembly object), Instance 844
(MeteringResults.RealTime_VIF_Power table) and Attribute 3 (data).
CSP Addressing
This is also known as ‘PLC-5 style’ or ‘PCCC’ addressing. Addresses are written
in the form ‘Axx:yy’ where A is a letter describing the function of the data table,
xx is the table number, and yy is the element within, or offset into, the table. For
example, ‘F53:0’ is the CSP address of the first element in the
MeteringResults.RealTime_VIF_Power table. PCCC messaging can be used to
read or write a single data element or a range of data elements within a data table.
Data Types
The PowerMonitor 5000 unit stores data by using four data types:
• INT16, in which the 16-bit word can be represented by an integer value or
a bitmap
• REAL, using the 32-bit IEEE 754 floating-point format
• String, containing alphanumeric characters used for security and unit
descriptive information
• DWORD, a 32-bit structure typically containing bitmap status
information