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What is the resolution of LFr [Frequency Reference] and rFr [output frequency] of Altivar 61 / 71 range of drives.

By default, Altivar 61 / 71 ranges of drives have LFr and rFr - Frequency Resolution of 0.1 Hz
 
If higher frequency resolution is desired then follow the below steps.
 
Altivar 61/ 71 range of drives contains CMI [Extended Control Word] at its modbus register address of 8504.Setting of Bit 9 of CMI word decides the Frequency Reference resolution.
 
If bit 9 is 0 then Frequency resolution will be 0.1 Hz
If bit 9 is 1then Standardized value 16 signed bits based on the maximum frequency. The value 32767 corresponds to [Max frequency] (tFr).
 
The default value of [Max frequency] (tFr) is 60 Hz, and the resolution is then approximately 60/ 32767 = 0.0018 Hz. It means count value 1 to the register of Lfr will correspond to the
Frequency Reference of 0.0018 Hz and count value 32767 to the register of Lfr will correspond to the Frequency reference of 60 Hz
 
For example if value of [Max frequency] (tFr) is 50 Hz, and the resolution is then approximately 50/32767 = 0.0015 Hz. It means value 1 to the register of Lfr will correspond to the
Frequency Reference of 0.0015 Hz and value 32767 to the register of Lfr will correspond to the Frequency reference of 50 Hz
 
Note that this function has no effect on the speed reference (LFrd) or the output speed (rFrd).
 
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