Rockwell Automation 1408-EMxx PowerMonitor 1000 Unit - Manual (Page 13)

13 Publication 1408-UM001B-EN-P - May 2008 13
Chapter
2
Powermonitor 1000 Memory Organization
The power monitor memory is organized similarly to that of a PLC-5
or SLC 500 programmable controller. Data tables organize individual
data items of similar function. For example, the analog input setup
parameters are grouped in one data table, and voltage, current, and
frequency metering results in another.
Appendix A provides a detailed list of the power monitor data tables.
Data Table Addressing Data tables may be addressed in several ways.
•
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, F23:0 is the CSP address of the first element in the
energy metering results table.
•
CIP addressing. This is also known as DeviceNet addressing.
Addresses are of the form Object:Instance:Attribute. CIP
addressing allows addressing only a single element of an entire
data table. In CIP addressing, the energy metering results table
object 4 (Assembly object), instance 16 (energy results table)
and attribute 3 (data).
•
Modbus RTU addressing. The data tables may be addressed by a
Modbus RTU master using Modbus register addressing. The
Modbus protocol supports four types of data: Discrete Input,
Coil, Input Register, and Holding Register. The power monitor
supports Input Registers (read-only) with addresses in the 30000
range and Holding Registers (read-write or write only) with
addresses in the 40000 range. Using the same example as above,
the energy results table has a Modbus address range of
30401…30438
Data Table Access Controllers and client applications may read or write single element,
multiple elements or complete tables as permitted by the addressing
selected.
Each data table’s read/write access is listed in Appendix A .