ABB RELION 620 Series Technical Manual page 904

Section 14
Protection relay's physical connections
Table 624: 4-wire EIA-485 jumper connectors for COM2
Group
X4
X5
X6
X7
X8
X9
1) Default setting
898
Table 623: 2-wire EIA-485 jumper connectors
Group Jumper connection
X4 1-2
2-3
X5 1-2
2-3
X6 1-2
2-3
X7 1-2
2-3
X8 1-2
2-3
X9 1-2
2-3
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 X4, 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.
Jumper connection
1-2
2-3
1-2
2-3
1-2
2-3
1-2
2-3
1-2
2-3
1-2
2-3
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
Description
A+ bias enabled
1)
A+ bias disabled
B- bias enabled
1)
B- bias disabled
Bus termination enabled
1)
Bus termination disabled
B- bias enabled
B- bias disabled 1)
A+ bias enabled
1)
A+ bias disabled
Bus termination enabled
1)
Bus termination disabled
1MAC504801-IB E
Notes
COM2
2-wire connection
COM1
2-wire connection
Notes
COM2
4-wire TX channel
COM2
4-wire RX channel
620 series ANSI
Technical Manual