Hioki ST5520-01 - Internal Circuit Configuration

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Internal Circuit Conguration
7.3 Internal Circuit Conguration
NPN setting
External power
10
11
PLC, etc.
Output
Common
ISO_5V8
2 k
Ω
1 k
Ω
EXT I/O
MODE
selector
START1
STOP20
ERR
UPPER FAIL
9 ISO_COM
27 ISO_COM
NPN
10
Ω
PLC, etc.
Input
Common
Zener voltage 30 V
Do not connect external power to pin 8.
ST5520, ST5520-01
Internally isolated common
(Isolate from the instrument protective ground.)
Internally isolated
power supply
• Use ISO_COM as the common terminal for both input and output signals.
• If a high current ows to common wiring, branch the output signal common wiring
and input signal common wiring from the position close to the ISO_COM terminal.
• When supplying power from an external device, supply power to the external
power supply shown in the above gure.