A-5 Modbus TCP  
AC30V series Variable Speed Drive 
User-Defined Parameter Mapping 
The AC30 parameters may be mapped to the user-defined register area (00001 – 00256).  This allows parameters to be grouped together so that 
they may be accessed through a single Modbus request. 
To map parameters add the required parameter numbers to the user mapping table using parameter 1567 Modbus Mapping.  The following 
applies: 
•  The mapping starts at register 00001. 
•  Any valid fixed or application parameter may be added excluding password parameters and parameter arrays - individual elements of the 
array may be added however. 
•  Parameter strings may be added. 
•  The mapping ends on the first mapping entry of zero or when the mapping table is full. 
Note: The mapping may be modified at any time.  However no Modbus requests should be made when the mapping is being modified to avoid 
indeterminate response data. 
 
Unlike the fixed mapping, the user-defined parameter mapping will only use as many registers as necessary to accommodate the parameter.  An 
example is given below: 
 
Parameter Name  Data Type  No. of Registers  Start Register  End Register 
0  0627 Comms Control Word  WORD   1  00001  00001 
1  0681 Comms Reference  REAL  2  00002  00003 
2  0696 First Trip  USINT  1  00004  00004 
3  0661 Status Word  WORD  1  00005  00005 
4  0395 Actual Speed Percent  REAL  2  00006  00007 
5  0961 Drive Name  23-character STRING  
12  00008  00019 
6  0000         
 
The mapping table is continually checked for valid entries.  The diagnostic parameter 1632 Mapping Valid will be TRUE if all entries in the table 
are valid parameters.  If the diagnostic parameter is FALSE, meaning there are invalid entries, then Modbus requests are still accepted but the 
invalid entries will be skipped over and will occupy no registers in the mapping.