Mitsubishi Electric A1S66ADA, Руководство пользователя

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MELSEC-A
3 SPECIFICATION
3.4 A/D Conversion I/O Characteristic
The I/O characteristic of A/D conversion will be explained below.
(1) I/O conversion characteristic
The I/O conversion characteristic refers to the angle produced when the "offset
value" and "gain value" created when the analog values (voltage or current) from
outside the PLC are converted to digital values are connected with a straight line.
The I/O conversion characteristic refers to the angle produced by a straight line
that connects the "offset value" and "gain value" created when the digital values
set by the PLC CPU are converted to analog values (voltage or current).
(2) Offset value and gain value
Offset value and gain value are defined as follows:
(a) Offset value····The analog value (voltage or current) that makes the digital output
value "0."
(b) Gain value······The analog value (voltage or current) that makes the digital output
value "4000."
(3) I/O conversion characteristic
Examples of A1S66ADA's I/O conversion characteristic are shown below.
When the offset value is -10 V and gain value is 10 V
4000
3000
2000
1000
0
Offset value
Gain value
-10 0
10
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ig
ita
l o
ut
pu
t v
al
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Analog input voltage (V)
Voltage input characteristic
When the offset value is 0 mA and gain value is 20 mA
4000
3000
2000
1000
0
Offset value
Gain value
0
10 20
D
ig
ita
l o
ut
p
ut
v
a
lu
e
Analog input current (mA)
Current input characteristic