Fine Adjustment Of Frequency Setting Signal - Toshiba TOSVERT VF-S11 Instruction Manual

6.5.4
f470 : VIA input bias
f471 : VIA input gain
f472 : VIB input bias
f473 : VIB input gain
• Function
The figure below shows the characteristic of the frequency setting signal input through the VIA and VIB
terminals and that of the output frequency.
Output frequency (Hz)
6
Maximum frequency
f470, f472
f470, f472
*
*

Fine adjustment of frequency setting signal

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 f201 to f213.
Large
0
0%
0V
4mA
Freguency setting signal (VIA, VIB input value)
Bias adjustment of VIA and VIB input terminals (f470 and f472)
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 f470 or f472 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 (f471 and f473)
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 f471 or f473 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.
Large
Small
Default setting
Small
100%
10Vdc
20mAdc
F-24
E6581158
f471, f473
f471, f473