ABB RELION 670 Series Installation Manual page 73

1MRK514024-UEN A
100k W
IEC07000242 V1 EN-US
Figure 46: Schematic view of soft earth
Earthing
Three different kinds of earthing principles can be set (used for fault tracing):
1. Direct earth - The normal earthing is direct earth, connect terminal 2 directly to the
chassis.
2. No earth - Leave the connector without any connection.
3. Soft earth - Connect soft earth pin (3), see figure
X.21 connector
Table 19:
Pin number
1
2
3
4
6
8
9
10
11
13
5,7,12,14,15
Installation manual
I/O
100nF
Soft ground
en07000242.vsd
Pinout for the X.21 communication connector
Signal
Shield (earth)
TXD A
Control A
RXD A
Signal timing A
Earth
TXD B
Control B
RXD B
Signal timing B
Not used
45
Section 6
Connecting
67