Yokogawa Value Series FX1000 - Manual (Page 72)

2-8
IM 04L21B01-17EN
Connection example to the host device
You can connect the FX to a host device that has an RS-232, RS-422A, or RS-485 port.
Use a converter to connect to an RS-232 port. See the following connection examples for
typical converter terminals. For details, see the manual that comes with the converter.
RS-422A/485 Port Converter
SDA(–) TD(–)
SDB(+) TD(+)
RDA(–) RD(–)
RDB(+) RD(+)
SG SHIELD
FG EARTH
There is no problem of connecting a 220 Ω terminator at either end if YOKOGAWA’s PLCs or
temperature controllers are also connected to the communication line.
• Four-wire system
Generally, a four-wire system is used to connect to a host device. In the case of a
four-wire system, the transmission and reception lines need to be crossed over.
Terminator (external) 120 Ω 1/2W or greater
#1
Do not connect terminators to #1 through #n-1.
RS-422A/485
terminal on the FX
#2 #n
(#n 32)
Terminator (external)
Host device
side
SG
RDB( + )
RDA( - )
SDB( + )
SDA( - )
FG
SG
RD B
RD A
SD B
SD A
(SG)
(RD B)
(RD A)
(SDB)
(SDA)
FG
SG
RD B
RD A
SD B
SD A
(SG)
(RD B)
(RD A)
(SDB)
(SDA)
FG
SG
RD B
RD A
SD B
SD A
(SG)
(RD B)
(RD A)
(SDB)
(SDA)
• Two-wire system
Connect the transmission and reception signals with the same polarity on the
RS-422A/485 terminal block. Only use two wires to connect to the external device.
Terminator (external) 120 Ω 1/2W or greater
#1
Do not connect terminators to #1 through #n-1.
RS-422A/485
terminal on the FX
#2 #n
(#n 31)
Terminator (external)
Host device
SG
RDB( + )
RDA( - )
SDB( + )
SDA( - )
FG
SG
RD B
RD A
SD B
SD A
(SG)
(B)
(A)
(B)
(A)
FG
SG
RD B
RD A
SD B
SD A
(SG)
FG
SG
RD B
RD A
SD B
SD A
(SG)
(B)
(A)
2.3 Connecting the FX