Mitsubishi Electronics 520 540 Air Conditioner User Manual


 
51
Handling of the RS-485 connector
1
WIRING
<Wiring methods>
1) Wiring of one RS-485 computer and one inverter
2) Wiring of one RS-485 computer and "n" inverters (several inverters)
REMARKS
*1. Make connection in accordance with the instruction manual of the computer to be used
with. Fully check the terminal numbers of the computer since they change with the model.
*2. The inverters may be affected by reflection depending on the transmission speed or
transmission distance. If this reflection hinders communication, provide a terminating
resistor. When the RS-485 connector is used for connection, a terminating resistor cannot
be fitted, so use a distributor. Connect the terminating resistor to only the inverter remotest
from the computer. (Terminating resistor: 100
)
Receive data
Receive data
FG
RS-485 connector
RSB
CSB
RSA
CSA
SG
SDB
SDA
RDB
RDA
SG
RDB
RDA
SDB
SDA
(*1)
Inverter
0.2mm or more
Computer Side Terminals
Signal
name
Description
Send data
Request to send
Signal ground
Frame ground
Send data
Request to send
Clear to send
Clear to send
Cable connection and signal direction
10 BASE-T Cable
2
SDB
SDA
RDB
RDA
FG
SG
CSB
CSA
RSB
RSA
RDB
RDA
SDB
SDA
SG SGSG
RDB
RDA
SDB
SDA
RDB
RDA
SDB
SDA
Computer
Terminating
resistor
(*2)
Cable connection and signal direction
10 BASE-T Cable
(*1)
Station 1 Station 2 Station n
Inverter
Inverter Inverter