User manual

33
MC-III™ EXP Flow Analyzer Section 2
RS-485 Output
The RS-485 output is required for communication with the interface software. Wiring diagrams are provided
for a permanent connection (Figure 2.16), as well as for temporary laptop connections using an RS-485 to RS-
232 converter (Figure 2.17).
The RS-485 output may also be used to install an external communications adapter for connecting a
laptop without opening the enclosure. See Explosion-Proof Communications Adapter, page A-3, and USB
Communications Adapter, page A-6, for details.
Additionally, in a CSA-approved device, the RS-485 output is approved for intrinsically safe installations. An
intrinsically safe installation requires an intrinsically safe barrier assembly with a conduit seal (Figure 2.18,
page 34). In such installations, only the turbine owmeter input may be used.
A
B
TB1
PULSE
INPUT
RESET
INPUT
TFM
A&S
GND
TB
3
EXT POWER
TB2
RS485
SLAVE
4-20
OUT
PULSE
OUT
6
-
3
0
V
D
C
RS-485
Communications
J1
J2
RESET
SWITCH
BATTERY
Figure 2.16—RS-485 output (permanent connection)
TB1
PULSE
INPUT
RESET
INPUT
TFM
A&S
GND
TB
3
EXT POWER
TB2
RS485
SLAVE
4-20
OUT
PULSE
OUT
6
-
3
0
V
D
C
J1
J2
RESET
SWITCH
BATTERY
TD(B)
TD(A)
GND
RS-232
9 - PIN
CONNECTOR
Part No.
9A-101283116
TX+
TX-
Figure 2.17—RS-485 output (connection to laptop with 9-pin converter)