Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 User Manual, Firmware rev. 3.0 or LATER - Manual (Page 307)

Publication 1404-UM001F-EN-P - November 2009 307
Sample Applications Appendix C
The MAC ID is the node number of the device that the DeviceNet
scanner is communicating to; this example uses node 5.
Word M0:1.227
The class number is the first word of the transaction body; class 4 is
used to retrieve the real-time data assemblies.
Word M0:1.2278
The instance number is the second word of the transaction body;
instance 14 is used to retrieve the real-time voltage, current, and
frequency metering information.
Word M0:1.229
The attribute number is the third word of the transaction body;
attribute 3 is used to get the metering information.
Word M0:1.226
Service MAC ID
Service x 256 + MAC ID
14 x 256 + 5
3589
Word M0:1.227
Class
4
Word M0:1.2278
Instance
14
Word M0:1.229
Attribute
3