Omron GRT1 - 11-2007 Operation Manual page 86

Digital I/O Units
Component Names and Functions (Same for GRT1-ID4 and GRT1-ID4-1)
Internal Circuits
GRT1-ID4 (NPN)
LED indicators
ID4
Indicate the Unit's status.
0
2
Terminal Block
Base block
TS
1
Test pin
3
Release button
Terminal insertion hole
Main block
I/O LED
Internal circuits
Internal circuits
Section 4-6
Terminal block
0
V
G
3
V
G
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