Lon/Spa Bus Communication On The Rear Connector X3.3; Front Rs-232 Connection For A Pc; Parallel Communication Support - ABB REM 543 Technical Reference Manual

ABB Network Partner
4.1.10.1.
4.1.10.2.
4.1.10.3.
REM 543 Protection,
Monitoring and Control

LON/SPA bus communication on the rear connector X3.3

The machine terminal supports both SPA bus protocol and LON bus communication
according to the ABB LON Application Guideline. The bus communication protocol
for the rear interface RS-485 (connector X3.3) is selected with the "Protocol 3" setting
parameter in the menu Communic. lib./General. The other communication parameters
for the rear RS-485 interface are also set in the Communication menu of the REM 543
machine terminal.

Front RS-232 connection for a PC

The opto-connection on the front panel isolates the PC galvanically from the machine
terminal. The opto-connection on the front panel consists of two parts: a transmitter
stage and a receiver stage. The front connector for the PC is standardized for ABB relay
products and requires a specific opto-cable (ABB art. No 1MKC950001-1). The cable is
connected to the serial RS-232 port of the PC. The optical stage of the cable receives its
power supply from the RS-232 signals. The cable works correctly within the whole
range of the RS-232 levels up to 9.6 kbps.
The following serial communication parameters should be used for the RS-232:
• number of data bits: 7
• number of stop bits: 1
• parity: even
• baud-rate: 9.6 kbps (default)

Parallel communication support

If a PC is connected to the front RS-232 interface for parameterization, the RS-485
interface on the rear side of the machine terminal behaves differently depending on
whether the SPA bus or the LON bus is selected for the rear interface as shown below.
Front inter- Rear interface
face X3.3
SPA SPA
SPA LON
Technical Reference Manual
Function
when the front connector is "active", the SPA in the rear
side connector is not communicating
SPA address is the same when communicating via
front and rear connector
system global password
SPA and LON use independent node numbers
when the front connector is "active", transparent SPA
write commands are inhibited via the LON bus
system global password; operation authorization via
LON or SPA according to the same password
Part 1, General
Page 41