ABB REF 542plus, Product Manual

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Feeder Terminal REF 542plus
1MRS756269
General (cont´d)
4
A070118
Fig. 2 REF 542plus installed in an air-insulated switchgear (AIS).
REF 542plus is composed of two parts: a
base unit and a separate human machine
interface (HMI). The base unit contains the
power supply, the processor board, the analog input board and binary input and output (I/O)
modules, as well as optional modules for sup-
plementary functions. The base unit and a
HMI are connected with a serial cable.
Block diagram
A050397
Fig. 3 REF 542plus block diagram.
HMI
The HMI is a stand-alone unit with its own
power supply. It can be installed on the low
voltage (LV) compartment door or in a dedi-
cated compartment close to the base unit.
The HMI can be used to set the protection
parameters to locally operate the switching
devices in the switchgear and to visualize
events and measurements. A shielded, iso-
lated twisted pair according to the RS-485
standard interface connects the HMI to the
base unit.
Fig. 4 shows an installation of the base unit
and the HMI control unit in the LV compart-
ment.
CP
Communicatio n P rocessor
RX TX
CP
Communication Processor
RX TX
IL1
IL2
IL3
UL1
UL2
UL3
Io
IL1
IL2
IL3
UL1
UL2
UL3
Io
start L1
start L2
start L3
Release/Trip
Autoreclosure
µC
Control
DSP
Protection
Measurement
Vo
Analog Input Module
Main Board
Binary Input Output Module(s)
0/4...20mA
Analog Output Module
Analog Input Module
Communication Module
0/4...20mA
CAN Eth.
T
ime
Synch.
Binary
inputs
Binary
outputs
A050397-c