YASKAWA E7U, Руководство по программированию

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Programming 70
H3 Analog Inputs
H3-02 Terminal A1 Gain Setting
Setting Range: 0.0 to 1000.0%
Factory Default: 100.0%
H3-03 Terminal A1 Bias Setting
Setting Range: -100.0% to +100.0%
Factory Default: 0.0%
In order to have the Drive properly interpret an analog input, it may be necessary to apply a gain and/or a bias to the signal. The
analog inputs have a resolution of 11 bits (1024 steps). Using the factory default settings for the analog input’s gain and bias, the
0-10Vdc or 4-20mA signal at the analog input will yield a 0-100% speed command span.
Note: 11 bits if 0 to 10 Vdc (A1, A2, A3) and 10 bits if 4-20mA (A2 only).
Fig. 48 Output Frequency as Commanded Via Analog Input
If a different span of analog input signal is desirable, it will be necessary to adjust the gain, the bias, or both to allow the analog input
level to generate the desired frequency command. Adjustment of the gain setting will change the speed command that is equivalent
to the maximum analog input (10Vdc or 20mA). If, for instance, the gain is increased to 200%, then 10Vdc or 20mA will be
equivalent to a 200% speed command and 5 VAC or 12mA will be equivalent to a 100% Speed Command. Since the Drive output
is limited by the maximum frequency parameter (E1-04), 0-5Vdc or 4-12mA will now be equivalent to 0-100% speed command
span.
20mA
4mA
0V
10V
Gain = 100%
Bias = 0%
Ou
tp
ut
F
req
uen
cy
Analog Input Level Signal