Serial Interface (Modbus RTU)136 M-Max Series Adjustable Frequency Drive MN04020003E—October 2013 www.eaton.comData Storage with ModbusThe information is stored in one input and one holding register.The registers are the memory location of the data. The memory size of each register is1 word.Modbus-Register-MappingThe register mapping enables the processing in MMX of the content listed in the followingtable via Modbus RTU.Each content in this table is assigned an ID number (abbreviation of the register numbers).This ID number is used in M-Max for the communication with Modbus RTU.Example: Control word (ID 2001)With some PLC manufacturers, the interface driver for Modbus RTU communication maycontain an offset of +1 (the ID to be used would then be 2000 instead of 2001).When processing values, the comma is not included, for example, the motor current (ID 2106)in the display of the MMX is shown as 0.35 A but is transferred via Modbus as 0023 (hex)(0035 [dec]).Register Numbers Type Name30001–39999 Read only (ro = read only) Input-register40001–49999 Read/write (rw = Read/write) Holding registerGroup Register Numbers ID Range Assignment of the ID NumbersDisplay values 40001–40098 (30001–30098) 1...98 Parameter list: (see “Appendix A” starting onPage 142)Failure code 40099 (30099) 99 Error list: (see “Error and Warning Messages” startingon Page 56)Parameters 40101–40999 (30101–30999) 101...1999 Parameter list: (see “Appendix A” starting onPage 142)Input process data 42001–42099 (32001–32099) 2001...2099 (See Page 137)Output process data 42101–42199 (32101–32199) 2101...2199 (See Page 138)ValueID Register Numbers2001 32001/42001Application Communication of Modbus RTU Memory location of the data
