YASKAWA F7 Programming Manual page 105

Adjustment of the bias setting will likewise adjust the frequency reference that is equivalent to the minimum analog input
level (0Vdc). If, for instance, the bias is set to –25%, then 0Vdc will be equivalent to a –25% frequency reference. Since the
minimum frequency reference is 0% an analog input of 2.5 to10Vdc will now be equivalent to 0-100% speed command span.
As a further example, for an inverse-acting frequency reference, set the bias= 100% and the gain= 0%. The minimum analog
input level (0Vdc) will produce a 100% frequency reference and the maximum analog input level (10Vdc) will produce a 0%
frequency reference.
H3-04 Terminal A3 Signal Level Selection
Setting
0 0 to 10 Vdc
1 -10 to +10 Vdc (factory default)
The H3-04 parameter (Terminal A3 Signal Level) allows the programmer to specify the signal that will be applied to the A3
analog input. The A3 analog input can accept either a 0 to10 Vdc or -10 to +10 Vdc signal as a reference.
H3-05 Terminal A3 Function Selection
Setting Range: 0 to 1F
Factory Default: 2: Auxiliary Frequency Reference 1
Parameter H3-05 performs the same function for the A3 analog input that parameter H3-09 performs for A2 analog input.
Please refer to the parameter description for H3-09 for details. The level of the A3 analog input, as a percentage of the
maximum input, can be viewed by the U1-17 monitor.
H3-06 Terminal A3 Gain Setting
Setting Range: 0.0 to 1000.0%
Factory Default: 100.0%
H3-07 Terminal A3 Bias Setting
Setting Range: -100.0% to +100.0%
Factory Default: 0.0%
Parameters H3-06 and H3-07 perform the same function for the A3 analog input that parameters H3-02 and H3-03 perform for
the A1 analog input. Please refer to the parameter description for H3-02 and H3-03 for details.
Gain = 100%
0V
4mA
Bias = -25%
Fig. 65 Output Frequency with Reduced Bias Setting
Bias
Gain = 100%
Gain
Bias = 0%
Fig. 66 Output Frequency with Inverted Gain and Bias Settings
Description
Programming 97
10V
20mA
2.5V
8mA
Analog Input Signal
Analog Input Level
0V
10V
4mA 20mA