Omron E5EK, User Manual

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6.2 Preparing for Communications
E5EK
6--3
6.2 Preparing for Communications
For details on wiring when the communications function is used, see
Chapter 2 Preparations.
J
Cable connections
•
Only one controller can be connected to the host computer.
(1:1 connection)
•
The cable length should not exceed 15 meters.
•
Use shielded twisted-pair cables (AWG28 or more) for the cables.
RS-232C
No.
20 SD
RD 19
18 SG
E5EK-T
RS-232C
No.
20 SD
RD 19
18 SG
E5EK-T
IBM-PC/XT
DE-25
Female
DTE
(SD) TXD
(RD) RXD
(RS) RTS
(CS) CTS
(SG) COMMON
(ER) DTR
(DR) DSR
2
3
4
5
20
6
7
FG 1
(RD) RXD
(SD) TXD
(ER) DTR
(SG) COMMON
(RS) RTS
(CS) CTS
(DR) DSR
2
3
4
5
8
6
7
FG 1
25 pins
IBM-PC/AT
DE-25
Female
DTE
9 pins
•
1:1 or 1:N connections are allowed. In a 1:N connection, up to 32 con-
trollers including the host computer can be connected.
•
The total cable length should not exceed 500 meters.
•
Use shielded twisted-pair cables (AWG28 or more) for the cables.
•
Attach terminators to the controllers at both ends of the series of con-
trollers connected in an open configuration. For example, in the fol-
lowing configuration, connect the terminator to unit No.30, and do
not connect terminators to unit Nos.0 to 29.
•
Use terminators having a resistance of 240
Ω
(1/2 W). The total resis-
tance of both ends should be at least 100
Ω
.
Host computer E5EK-T (No.0) E5EK-T (No.30)
RS-422 RS-422 RS-422
Shielded cable
TerminatorX2
(240
Ω
1/2 W)
RDA
RDB
SDA
SDB
SG
FG
SDA 22
No.
SDB 21
RDA 19
RDB
20
SG 18
SDA 22
No.
SDB 21
RDA 19
RDB
20
SG 18
F
RS-232C
F
RS-422