Galvanic Rs485 Communication Module - ABB RES670 Technical Manual

1MRK 511 408-UUS A
23.2.12
23.2.12.1
23.2.12.2
Phasor measurement unit RES670 2.2 ANSI
Technical manual

Galvanic RS485 communication module

Introduction
The Galvanic RS485 communication module (RS485) is used for DNP3.0 and IEC
60870-5-103 communication. The module has one RS485 communication port. The
RS485 is a balanced serial communication that can be used either in 2-wire or 4-wire
connections. A 2-wire connection uses the same signal for RX and TX and is a
multidrop communication with no dedicated Master or slave. This variant requires
however a control of the output. The 4-wire connection has separated signals for RX
and TX multidrop communication with a dedicated Master and the rest are slaves. No
special control signal is needed in this case.
Design
RS485 is a PC-MIP card, and it is factory mounted as a mezzanine card on the Analog
digital conversion module (ADM).
RS485 connector pinouts
The arrangement for the pins in the RS485 connector (figure 321) are presented in
table 665:
Table 665: The arrangement for the pins
Pin Name 2-wire
1 RS485+
2 RS485–
3 Term
4 N.A.
5 N.A.
6 N.A.
Name 4-wire Description
TX+ Receive/transmit high or transmit high
TX– Receive/transmit
T-Term Termination resistor for transmitter (and receiver in
2–wir case) (connect to TX+)
R-Term Termination resistor for receiver (connect to RX+)
RX– Receive low
RX+ Receive high
Section 23
IED hardware
SEMOD174899-1 v1
SEMOD158664-5 v3
SEMOD158668-1 v1
SEMOD158670-4 v3
SEMOD158670-10 v1
845