Bedford B550-2001, Инструкция по установке и быстрому запуску

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5-26
Pr.49
Potentiometer Bias Polarity
a
Factory Setting: 00
Settings 00 Positive Bias
01 Negative Bias
This parameter sets the potentiometer Bias Frequency to be positive or negative.
Pr.50 Potentiometer Frequency Gain
a
Factory Setting: 100.0
Settings 0.10 to 200.0% Unit: 1%
This parameter sets the ratio of analog input vs frequency output.
Pr.51
Potentiometer Reverse Motion Enable Factory Setting: 00
Settings 00 Reverse Motion Disabled in negative bias
01 Reverse Motion Enabled in negative bias
Pr.48 to Pr.51 are used when the source of frequency command is the analog signal (0 to
+10V DC or 4 to 20mA DC). Refer to the following examples.
Example 1:
Set Pr.00=1 to command frequency with the potentiometer on keypad or Pr.00=2 (4 to 20mA
current signal) potentiometer/current signal of external terminal.
Max.
Output
Freq.
60Hz
Pr.03
0Hz
0V
4mA
5V
12mA
10V
20mA
Factory Settings
Pr.03=60Hz--Max. output Freq.
Pr.48=0%--bias adjustment
Pr.49=0 -- bias polarity
Pr.50=100% -- pot. freq. gain
Pr.51=0 -- REV disable in
negative bias
Potentiometer Scale
Hz
0V
10V
30
0
60
Example 2:
A Bias Adjustment (16.7% of 60Hz) determines the Output Frequency to be 10 Hz with the
potentiometer set at 0V as shown. Notice that the entire V/F is transposed accordingly. An
analog input voltage 0-8.33V (or current 4-13.33mA) would set frequency as 0-60Hz.Once the
Maximum Output Frequency is reached any further increase on the potentiometer will not
increase output frequency (If you want to use the range of 60Hz, please refer to the example
3).
B550
Series
sensorless vector frequency drive