RKI Instruments M2 Rig Monitor - Manual (Page 40)

35 M2 Rig Monitor Operator’s Manual
Recommended Modbus Wiring
The recommended Modbus wiring for the Rig Monitor is illustrated in Figure 12 below. In
this configuration, 5 wires are used for wiring the Rig Monitor into a Modbus system.
Figure 12 also illustrates typical alarm device wiring.
Figure 12: Recommended Modbus Wiring
Termination Jumper
The Rig Monitor includes a 2-pin termination header (see Figure 4) that is used when the
Rig Monitor is used in a Modbus system. Every Rig Monitor is supplied with a
termination jumper (a jumper block) installed onto this header. If the Rig Monitor is not
used in a Modbus system, this jumper has no function. When the Rig Monitor is installed
in a Modbus system, this jumper must be installed in an Rig Monitor that is at the end of a
Modbus line. Any Rig Monitor in a Modbus system that is not at the end of a line must
have the termination jumper removed (see Figure 13 & Figure 14 below).
Figure 13: Multiple M2 Rig Monitors in a Daisy Chain Configuration
C
N
C
NO
-
24 VDC
Factory
Wired
+
S
PW
R
/S
IG
FA
IL
PW
R
/S
IG
S
C
N
C
NO
FA
IL
To
Additional
M2s
Power
Converter
AL
A
R
M
2
A
B
C
RS
4
8 5
RS
4
8 5
A
B
C
AL
A
R
M
2
Input
Terminals
D1
D0
Power
Converter
Factory
Wired
24 V DC
-
+
Modbus
Controller
Common
C
N
C
NO
C
N
C
NO
TO
X
IC
O
X
Y
C
N
C
NO
AL
A
R
M
1 See
Detector
Wiring
See
Detector
Wiring AL
A
R
M
1
C
N
C
NO
TO
X
IC
O
X
Y
Modbus
Master
M2
Termination
Jumper
Installed
M2
Termination
Jumper
Not Installed
M2
Termination
Jumper
Not Installed
M2
Termination
Jumper
Not Installed
M2
Termination
Jumper
Not Installed
ID = 128
ID = 127 ID = 126 ID = 125 ID = 1
Up to 128 M2s can be connected without a repeater.
RS-485 RS-485