Preparing for Operation
Chapter 4
Frequency Reference Gain
n39
Setting range 0.10 to 2.55
Factory setting 1.00 (times)
(times)
Unit of setting 0.01 (times)
Frequency Reference Bias
n40
Setting range –99 to 99 (%) Factory setting 0 (%)
Unit of setting 1 (%)
• These constants are used to set the relationship between analog voltage and refer-
ence frequencies when frequency references are input through control terminals FR
and FC.
• Frequency reference gain (n39): Specify the input voltage corresponding to the maxi-
mum frequency (n24) as a multiple of 10 V.
• Frequency reference bias (n40): Specify the reference frequency corresponding to in-
put voltage 0 V as a percentage of the maximum frequency (n24).
Explanation of Frequency Reference Gain and Bias
Gain setting = 10 V x (n39 setting)
Bias setting = Maximum frequency x (n40 setting)/100
Reference frequency
Maximum frequency
Bias setting
Input voltage
Gain setting
Example of Setting:
Operating the Inverter so that the Maximum Frequency is Reached when
the Voltage Increases from 0 to 5 V
Maximum frequency
Reference frequency
Settings:
n39 = 0.50 (times)
n40 = 0 (%)
Input voltage
4-22