9
3
ELECTRICAL CONNECTIONS…
3.3
Wall-mounted Instrument Connections – Fig. 3.4
✶
Note. Refer to Fig. 3.1 for Access to Terminals.
Caution. Slacken terminal screws fully before making connections.
Warning. The power supply earth (ground) must be connected to ensure safety to personnel, reduction
of the effects of RFI and correct operation of the power supply interference filter.
Fig. 3.4 Wall-mounted Instrument Connections
Power
Supply
Retransmission
Relay 1
Relay 2
Serial
Power
Supply
Retrans.
Relay 1
Relay 2
1
2
3
4
5
6
7
+
–
N
L
Serial
(If fitted)
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
–
–
–
–
–
–
Rx+
Rx–
Tx+
Tx–
0V
+
–
Retrans.
Output
Relays
1
2
3
4
5
6
–
–
–
–
–
–
NC
C
NO
NC
C
NO
Relay 1
Relay 2
Mains Supply
N
L
–
–
Neutral
Line
– Earth
Output
RS422/
RS485
Earth Stud (on case) –
see Fig. 3.1
NC
C
NO
Normally Closed
Common
Normally Open
=
=
=
Channel 2
Channel 1
1
3
–
–
+ve (Red)
–ve (Black)
Braid
D.O. Sensor
Earth Stud (on
case) – see Fig. 3.1
Channel 2
Channel 1
PT1000
Temperature Compensator
5
6
7
–
–
–
White
Green
Link
