YOKOGAWA YS80 Series, Руководство пользователя

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4-1
IM 01B04N01-02E
Principles of Operation
1
2
3
App
1
2
3
5
6
7
8
4
4.1 Principle of Operation
Input signal Ein passes through high-input resistor Rin (1 MΩ, 0 V input at input burnout),
and is converted into digital data in A/D conversion circuit. The digital data has signal
processing (square root characteristic etc.) in micro-processor to be Pulse Width Modulation
(PWM), then is converted into 1 to 5 V DC or 4 to 20 mA DC signals in output circuit through
optical-isolation circuit.
Output
Circuit
Input
Processing
Circuit
A/D
Conversion
Circuit
Supply
N–
L+
GND
–
+
+
–
Output
Circuit
A
B
Power
Supply
Circuit
Isolation Circuit
Micro-
processor
Isolation Circuit
F
H
1
2
+
–
V/I
Input (Ein)
Output 1 (1 to 5 V DC)
Output 2 (4 to 20 mA DC)
F0401.ai
Rin
Handy
Terminal
PC
(VJ77)
Figure 4-1 Functional Block Diagram
Chapter 4 Principles of Operation