Use Of Bias And Gain For Use Of Full Range; Use Of 0-5V Potentiometer Range Via Gain Adjustment; Use Of Negative Bias In Noisy Environment - Delta VFD-B User Manual

Chapter 5 Parameters|VFD-B Series
Example 3: Use of bias and gain for use of full range
This example also shows a popular method. The whole scale of the potentiometer can be used as
desired. In addition to signals of 0 to 10V and 4 to 20mA, the popular voltage signals also include
signals of 0 to 5V, 4 to 20mA or any value under 10V. Regarding the setting, please refer to the
following examples.
60Hz
10Hz
Bias
Adjustment
0Hz
0V
-2V
4mA
XV
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 shown in the
example below, you can set Pr. 01-00 to 120Hz to achieve the same results.
60Hz
30Hz
0Hz 0V
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).
5-50
Pr.01-00=60Hz--Max. output Freq.
AVI
Pr.04-00
Pr.04-01
Pr.04-02
Pr.04-03
Gain:(10V/(10V+2V))*100%=83.3%
10V
5V
Bias adjustment:((10Hz/60Hz)/(Gain/100%))*100%=20.0%
20mA
12mA
Gain
adjustment
Pr.01-00=60Hz--Max. output Freq.
AVI
Pr.04-00
Pr.04-01
Pr.04-02
Pr.04-03
Gain:(10V/5V)*100%=200%
10V
5V
ACI AUI
Pr.04-11 Pr.04-15=20.0%--Bias adjustment
Pr.04-12 Pr.04-16=0--Positive bias
Pr.04-13 Pr.04-17=83.3%--Input gain
Pr.04-14 Pr.04-18=0--No negative bias command
AUI
Pr.04-15=0.0%--Bias adjustment
Pr.04-16=0--Positive bias
Pr.04-17=200%--Input gain
Pr.04-18=0--No negative bias command
Revision July 2008, BE16, SW V4.08 & V5.00