ABB RED615 Technical Manual page 871

1YHT530004D05 D
615 series
Technical Manual
The bus is to be biased at one end to ensure fail-safe operation, which can be done
using the pull-up and pull-down resistors on the communication module. In 4-wire
connection the pull-up and pull-down resistors are selected by setting jumpers X3,
X5, X7 and X8 to enabled position. The bus termination is selected by setting
jumpers X6 and X9 to enabled position.
The jumpers have been set to no termination and no biasing as default.
Table 685: 4-wire EIA-485 jumper connectors for COM2
Group Jumper connection
1-2
X3 2-3
1-2
X5 2-3
1-2
X6 2-3
1-2
X7 2-3
1-2
X8 2-3
1-2
X9 2-3
Table 686: Jumper connectors for COM1 serial connection type
Group
X16
X15
X24
It is recommended to enable biasing only at one end of the bus.
IED physical connections
Description
A+ Bias enabled
A+ Bias Disabled
B- Bias enabled
B- Bias Disabled
Bus termination
enabled
Bus termination
disabled
B- Bias enabled
B- Bias Disabled
A+ Bias enabled
A+ Bias Disabled
Bus termination
enabled
Bus termination
disabled
Jumper connection
1-2
2-3
1-2
2-3
1-2
2-3
Section 13
Notes
COM2
4-wire TX channel
COM2
4-wire RX channel
Description
EIA-485 selected for COM1
FO_UART selected for COM1
Star topology selected for
FO_UART
Loop topology selected for
FO_UART
FO_UART channel idle state:
Light on
FO_UART channel idle state:
Light off
865