To perform explicit messaging to the PowerFlex 40 over EtherNet/IP, arm yourself with the PowerFlex 40 User Manual and the 22-COMM-E User Manual.
The PowerFlex 40 User Manual will give you the actual Parameter Numbers.
The PowerFlex 40 uses the very ordinary Parameter Object, so you can use the ordinary "Read Parameter" Message type that pre-fills the fields for the Service (0x0E, Get Attribute Single) and the Class (0x0F, Parameter), and the Attribute (0x01, Value).
All that you need to fill in is the Instance number which is the Parameter number.
Fault Code 01, Fault Code 02, Fault Code 03 are Parameters 7, 8, and 9.
It's more complex if you are using "multi-drive mode" or need to get Parameters from the 22-COMM-E itself.