Fine Adjustment Of Frequency Setting Signal - Toshiba TOSVERT VF-FS1 Instruction Manual

6.5.4

Fine adjustment of frequency setting signal

 : VIA input bias
 : VIA input gain
 : VIB input bias
 : VIB input gain
• Function
These parameters are used to fine adjust the relation between the frequency setting signal input
through the analog input terminals VIA and VIB and the output frequency.
Use these parameters to make fine adjustments after making rough adjustments using the
parameters  to  .
The figure below shows the characteristic of the frequency setting signal input through the VIA and VIB
terminals and that of the output frequency.
, 
* Bias adjustment of VIA and VIB input terminals (  and  )
To give leeway, the inverter is factory-adjusted by default so that it will not produce an output until a
certain amount of voltage is applied to the VIA and VIB input terminals. If you want to reduce the leeway,
set  or  to a larger value. Note that specifying a too large value may cause an output
frequency to be output, even though the operation frequency is 0 (zero) Hz.
* Gain adjustment of VIA and VIB input terminals (  and  )
The inverter is factory-adjusted by default so that the operation frequency can reach the maximum
frequency, even though the voltage and current to the VIA and VIB input terminals are below the
maximum levels. If you want to adjust the inverter so that it will output the maximum frequency at the
maximum voltage and current, set  or  to a smaller value. Note that specifying a too small
value may cause the operation frequency not to reach the maximum frequency, even though the
maximum voltage and current are applied.
Frequency setting signal (VIA, VIB input value)
F-23
E6581381
, 
6