Operating Instructions

Descriptions of Parameter Settings
Descriptions of Parameter Settings
128 | 443
Using negative bias to set the frequency greatly reduces the noise interference. In a noisy environment, do NOT
use signals less than 1 V to set the drive’s operation frequency.
Pr.
Explanation
Settings
Default
03-10
Reverse setting when analog
signal input is negative frequency
0: Negative frequency input is not allowed.
The digital keypad or external terminal controls the forward and reverse
direction.
1: Negative frequency input is allowed.
Positive frequency = run in a forward direction; negative frequency = run
in a reverse direction.
The digital keypad or external terminal control cannot change the
running direction.
0
● Use this parameter only for AVI or ACI analog input.
● Requirements for negative frequency (reverse running)
Pr.03-10 = 1
Bias mode = Bias serves as the center
Corresponded analog input gain < 0 (negative); this makes the input frequency negative.
In using the analog input addition function (Pr.03-18=1), when the analog signal is negative after the addition,
you can set this parameter to allow or not allow the reverse running. The result after adding depends on the
“Requirements for negative frequency (reverse running)”.
● In the following diagrams:
– Black line: Curve with no bias.
– Gray line: curve with bias
Diagram 1
Diagram 02