Operation & Installation Manual V12-V6 2010-05-31.doc
31/05/2010
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B/B-: Frequency output inverted related to the line flow whereby this frequency output
will stop operating if data valid alarm on status bit C/C- will occur.
To do so the frequency output B/B- should be placed in series with status bit C/C- as
presented in Figure 5-3
A
A-
B
B-
C
C-
D
D-
Alarm
A
A-
A
A-
B
B-
B
B-
C
C-
C
C-
D
D-
D
D-
Alarm
Figure 5-3: Connecting diagram for turbine emulation.
5.3.3. Serial data communication (RS485)
Figure 5-4: Serial data communication RS485
The electronics has two independent serial ports operating in half duplex mode (switching
automatically between receiving and transmitting). The electrical connections of these ports
are galvanic isolated from each other and from the main circuit. Each port is connected by
means of terminals A and B and (optional) GND. The GND can be used for cable shielding.
It is recommended , even when only one port is used for data acquisition, to wire both serial
ports to the a location outside the hazardous area.. The second port, not connected to the
data acquisition system, can be used as a flexible interface for remote programming and
monitoring of the flow meter using the service tool (see service tool manual or section
