Mitsubishi Electric QJ71MB91 User Manual page 154

6
PRE-OPERATIONAL PROCEDURES AND SETTINGS
Terminating
R
resistor
Terminating
R
resistor
Terminating
resistor
6
- 17 6.5 Connection to a Target Device
6.5.2 How to connect the RS-422/485 interface
(c) Connection for 1:n communications when host is slave
1) When performing 1:n communication with third party master station (RS-422/
485 interface)
< For 4-wire communications >
QJ71MB91
Third party
master
SDA
SDB
RDA
RDB
SG
FG
Figure 6.16 Connection (for 1:n communication, 4 wires) when host is slave
< For 2-wire communications >
Third party
master
SDA
SDB
RDA
R
RDB
SG
FG
Figure 6.17 Connection (for 1:n communication, 2 wires) when host is slave
Third party
slave
SDA SDA
SDB SDB
RDA RDA
RDB RDB
SG SG
FG FG
QJ71MB91
SDA
SDB
RDA
RDB
SG
FG
QJ71MB91
SDA
R
SDB
RDA
R
RDB
SG
FG
QJ71MB91
Third party
slave
SDA
SDB
RDA
R
RDB
SG
FG
Terminating
resistor
Terminating
resistor
SDA
SDB
RDA
RDB
SG
FG