Schweitzer Engineering Laboratories SEL-749M - Figure 7.3 SEL Cable C227 A-SEL-749 M to DTE Device; Figure 7.4 SEL Cable C222-SEL-749 M to Modem; Figure 7.5 SEL Cable C272 A. SEL-749 M to SEL Communications Processor (Without IRIG-B Signal); Figure 7.6 SEL Cable C273 A. SEL-749 M to SEL Communications Processor (with IRIG-B Signal)

7.4
SEL-749M Relay Instruction Manual Date Code 20080918
Communications
Communications Interfaces
Figure 7.3 SEL Cable C227A–SEL-749M to DTE Device
Figure 7.4 SEL Cable C222–SEL-749M to Modem
Figure 7.5 SEL Cable C272A. SEL-749M to SEL Communications Processor
(Without IRIG-B Signal)
Figure 7.6 SEL Cable C273A. SEL-749M to SEL Communications Processor
(With IRIG-B Signal)
SEL-749M Relay
9-Pin Male
D Subconnector
25-Pin Female
D Subconnector
5
3
2
9
8
7
3
2
1
4
5
6
8
20
GND
TXD
RXD
GND
CTS
GND
RXD
TXD
GND
RTS
CTS
DSR
DCD
DTR
Pin
Func.
Pin
Func.
Pin # Pin #
*DTE Device
*DTE = Data Terminal Equipment (Computer, Terminal, etc.)
SEL-749M Relay
9-Pin Male
D Subconnector
25-Pin Female
D Subconnector
5
3
7
2
8
9
7
2
20
3
8
1
GND
TXD
RTS
RXD
CTS
GND
GND
TXD (IN)
DTR (IN)
RXD (OUT)
CD (OUT)
GND
Pin
Func.
Pin
Func.
Pin # Pin #
**DCE Device
**DCE = Data Communications Equipment (Modem, etc.)
SEL Communications Processor
9-Pin Male
D Subconnector
9-Pin Male
D Subconnector
2
3
5
7
8
3
2
5
8
7
RXD
TXD
GND
RTS
CTS
TXD
RXD
GND
CTS
RTS
Pin
Func.
Pin
Func.
Pin # Pin #
SEL-749M Relay
SEL Communications Processor
9-Pin Male
D Subconnector
9-Pin Male
D Subconnector
2
3
4
5
6
7
8
3
2
4
5
6
8
7
RXD
TXD
IRIG+
GND
IRIG-
RTS
CTS
TXD
RXD
IRIG+
GND
IRIG-
CTS
RTS
Pin
Func.
Pin
Func.
Pin # Pin #
SEL-749M Relay
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