Functionality - ABB REG670 Technical Manual

Section 21
IED hardware
21.2.16.3
1194
I/O
100k W
100nF
Soft ground
en07000242.vsd
IEC07000242 V1 EN
Figure 544: 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 924: Pinout for the X.21 communication connector
Pin number Signal
1 Shield (earth)
2 TXD A
3 Control A
4 RXD A
6 Signal timing A
8 Earth
9 TXD B
10 Control B
11 RXD B
13 Signal timing B
5,7,12,14,15 Not used

Functionality

The data format is HDLC. The speed for the transmission of the messages used is 64
kbit/s.
1MRK502052-UEN B
543
Technical manual