Delta VFD022B21A - Use of 0-5 V Potentiometer Range Via Gain Adjustment; Use of Negative Bias in Noisy Environment; Gain Adjustment to Use Full Potentiometer; Range

Chapter 5 Parameters_VFD-B Series
5-56
Revision 10/2005, BE13, SW V4.08
Example 4: Use of 0-5V potentiometer range via gain adjustment
This example shows a potentiometer range of 0 to 5 Volts. Instead of adjusting gain as example below, you can
set Pr. 01-00 to 120Hz to achieve the same results.
Pr.01-00=60Hz--Max. output Freq.
AVI AUI
Pr.04-00 Pr.04-15=0.0%--Bias adjustment
Pr.04-01 Pr.04-16=0--Positive bias
Pr.04-02 Pr.04-17=200%--Input gain
Pr.04-03 Pr.04-18=0--No negative bias command
Gain:(10V/5V)*100%=200%
60Hz
0Hz 0V
5V
30Hz
Gain
adjustment
10V
Example 5: Use of negative bias in noisy environment
In this example, a 1V negative bias is used. In noisy environments it is advantageous to use negative bias to
provide a noise margin (1V in this example).
60Hz
0Hz
0V
10V
Pr.01-00=60Hz--Max. output Freq.
AVI AUI
Pr.04-00 Pr.04-15=10.0%--Bias adjustment
Pr.04-01 Pr.04-16=1--Negative bias
Pr.04-02 Pr.04-17=100%--Input gain
Pr.04-03 Pr.04-18=0--No negative bias command
Gain:100%
Bias adjustment:((6Hz/60Hz)/(Gain/100%))*100%=10.0%
Negative
bias 6Hz
1V
54Hz
Example 6: Use of negative bias in noisy environment and gain adjustment to use full potentiometer
range
In this example, a negative bias is used to provide a noise margin. Also a potentiometer frequency gain is used to
allow the Maximum Output Frequency to be reached.