Contec BX-100n-DC5000-C01, User Manual, Page: 53 / 145

4. Each Component Function
46
BX-100n User’s manual
RX-(11)
TXD
RTS
RXD
0
1
R
D
TE_GATE
RE_GATE
RS485 Terminator
Control
Enabled : On
Disabled : Off
120k Ω
RX+(3)
TX-(10)
TX+(2)
0 : Controlled by RTS
TE_SEL
1 : Controlled by TE_GATE
0 :Transmission
prohibited
1 :Transmission
permitted
1 :Transmission
prohibited
0 :Transmission
permitted
1 :Receiving
prohibited
0 :Receiving
permitted
Figure 4.16. Full-Duplex Connection Method
External I/O Circuit
Internal
reset
RAS connector
Input
contact
External power
(12 - 24VDC)
(External circuit)
4.7k
Ω
1/4W
4.7k
Ω
(PI 0 - 2)
(PCOM2)
PC817
(IN)
Figure 4.17. Input Circuit
(PO 0 - 2)
(NCOM)
PC817
2N3904
(External circuit)
External power
(Max. 30VDC)
Loading
RAS connector
4.7k Ω
510 Ω
Figure 4.18. Output Circuit