ABB 615 Series ANSI, Technical Manual

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1MAC050144-MB C
Section 12
IED physical connections
615 series ANSI 683
Technical Manual
Table 550: 2-wire EIA-485 jumper connectors
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.
Table 551: 4-wire EIA-485 jumper connectors for COM2
Group Jumper connection Description Notes
X4 1-2 A+ bias enabled COM2
2-wire connection
2-3 A+ bias disabled
X5 1-2 B- bias enabled
2-3 B- bias disabled
X6 1-2 Bus termination
enabled
2-3 Bus termination
disabled
X7 1-2 B- bias enabled COM1
2-wire connection
2-3 B- bias disabled
X8 1-2 A+ bias enabled
2-3 A+ bias disabled
X9 1-2 Bus termination
enabled
2-3 Bus termination
disabled
Group
Jumper
connection
Description Notes
X4 1-2 A+ bias enabled COM2
4-wire TX channel
2-3
A+ bias disabled
1
1. Default setting
X5 1-2 B- bias enabled
2-3 B- bias disabled
X6 1-2 Bus termination enabled
2-3 Bus termination disabled
X7 1-2 B- bias enabled COM2
4-wire RX channel
2-3 B- bias disabled
X8 1-2 A+ bias enabled
2-3 A+ bias disabled
X9 1-2 Bus termination enabled
2-3 Bus termination disabled
It is recommended to enable biasing only at one end of the bus.