Yaskawa P7 Drive User Manual - Manual (Page 120)

Programming 5 - 36
H3-09 Terminal A2 Function Selection
The A2 analog input can be programmed to perform many different functions. The setting of parameter H3-09 determines
which of the following functions the A2 analog input will perform.
Function: Frequency Bias
Setting: 0
By setting H3-09= “0: Frequency Bias”, the A2 analog input will serve as a bias signal to the A1 Speed Command. The effect
of using A2 for a frequency bias is that the level of the A2 analog input will be summed with the level of the Speed Command
analog input (A1). For example, if H3-02= 100%, H3-03= 0%, and the A2 analog input level is 1 Vdc, the Speed Command
profile will look like the figure below. If A1= 0 Vdc the Speed Command would be 10% of the programmed maximum
frequency because A1 (0 Vdc) + A2 (1 Vdc) = 1 Vdc.
Fig. 28 Effect of Frequency Bias Function on Speed Command
It should be noted that the bias applied by the A2 analog input functions differently than the level set by the H3-03. If both
biases are used simultaneously they will sum together.
The level of the A1 analog input, as a percentage of the maximum input (either 10 Vdc or 20 mA), can be viewed by the U1-
15 monitor. The level of the A2 analog input, as a percentage of the maximum input, can be viewed by the U1-16 monitor.
The bias applied by setting H3-09= “0: Frequency Bias”, can be used in conjunction with the parameter bias H3-03. In that
case the H3-03 bias is applied first which changes the slope of the Speed Command vs. Terminal A1 Voltage graph. Then the
level of the A2 analog input is summed with the A1 analog input level, which in effect shifts the Speed Command vs. Terminal
A1 Voltage graph upwards or downwards but does not change the slope of the line.
Setting Description
0 Frequency Bias
2 Aux Reference (factory default)
B PI Feedback
D Frequency Bias 2
E Motor Temperature
16 PI Differential
1F Not Used
0V
10%
Bias
Terminal A1 Voltage
S
p
eed
Com
m
and
10 9V
H3-02
1V
10
V
Input
V
A2 Input