REM 543 Protection,
Monitoring and Control
Page 53
Technical Reference Manual
Part 1, General
ABB Network Partner
4.2.2.1.
Definition of power direction
When the overexcited generator (G) feeds the inductive load (motor M), the real and
reactive power signs are as shown in the figure below.
The connections in relay A and
relay B are identical (e.g. as in the terminal diagram of REM543 above) and the power
direction parameter (e.g. in function blocks UPOW_, OPOW_, MEPE7) in both relays
is set to "forward".
Fig. 4.2.2.1.-1. Definition of power direction in REM 543.
4.2.3.
Terminal connections
All external circuits are connected to the terminal blocks on the rear panel. Terminal
block X1.1 for the measuring transformers consists of fixed screw terminals fastened to
the energizing input module. Each terminal is dimensioned for one max. 6 mm
2
or two
max. 2.5 mm
2
wires.
ABB sensors (Rogowski coil or voltage divider) are connected to the connectors
X2.1...X2.8. A special type shielded twin BNC connector (e.g. type AMP 332225 or
Amphenol 31-224) is used to improve reliability and protection against disturbances.
The current and/or voltage divider used must have a connector that is compatible with
the machine terminal. If the machine terminal is ordered without sensor inputs, the sen-
sor connectors X2.1...X2.8 are missing. Short-circuit connectors (1MRS1200515) must
be connected to unused sensor inputs.
The serial interface RS-485 on the rear panel (connector X3.3 ) is used for connecting
the machine terminal to the SPA bus or the LON bus. The SPA/LON bus is connected
via the connection module type RER 103. RER 103 is fitted to the 9-pole D-type sub-
miniature connector and screwed to the rear panel.
The connector X4.1 is a 18-pin detachable multi-pole connector strip with screw termi-
nals. The male part of the multi-pole connector strip is fastened to the printed circuit
boards. The female parts including accessories are delivered together with the machine
terminal. The female connector part can be secured with fixing accessories and screws.
One max. 1.5 mm
2
wire or two max. 0.75 mm
2
wires can be connected to one screw ter-
minal.
G
M
ind
+P
+Q
-P
-Q