AFLOWT BUF, Руководство по эксплуатации

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NOTES:
1. Flow rate and volume of reverse flow and negative values of total
volume are indicated by negative sign.
2. Totalized volume is the algebraic (considering the sign of the flow) sum
of flow volumes totalized for both forward (positive) and reverse
(negative) flows.
3. Counters are overflowed at V

2

10
9
m
3
and restart from zero.
1.4.4.2. In SERVICE and ADJUSTMENT mode, the LCD is constantly on. In
OPERATION mode, measurement results listed in Table 4 cyclically
appear on the display on pressing the relevant button. With each
pressing of the button, the next parameter is indicated. When no button
is pressed during the period specified in the "
Service " window of
Viewer BUF-311 program, the LCD goes off.
1.4.5. External connections
1.4.5.1. RS-485 interface
RS-485 serial interface is used to control the flow meter, read
measurement results, data logs, configuration settings, and diagnostic
data as well as to modify configuration settings. The RS-485 interface
supports ModBus (RTU ModBus and ASCII ModBus).
RS-485 interface supports cable communications among a group of
several end users, one of which can be a PC, at a distance of up to
1200 m.
The speed of communication via RS-485 and other communication
parameters are set from a PC.
1.4.5.2 M-Bus interface
Interface M-Bus interface complies with the standard EN 60870-5.
The interface allows reading of the measured and archived data.
Interface connections are made via two wires, the polarity is not
important. The rate of exchange via interface M-Bus is set from a PC.
1.4.5.3. Universal output
The flow meter is equipped with 1 galvanically connected output.
Universal output can operate in the frequency, pulse and logical
modes. Diagrams of output stages and description of their operation are
given in Fig.B.2, see Appendix B of the present manual.
Functions, working modes, specifications of output signals and
disconnection of the outputs are specified programmatically (see
section 4.1.3). Options available are specified in Table C.2, see
Appendix C of the present manual.
Operation modes of Universal output.

In the frequency mode, measurement results are outputted in the
form of square pulse sequence with period-to-pulse duration ratio of
2 and pulse repetition rate proportional to the current flowrate value.
The frequency output can be scaled by specifying the values for
"
Maximum output frequency " and " Output conversion factor " pa-
rameters as well as for " Lower limit by flowrate " and " Up. limit by
flowrate " threshold flowrate values that correspond to zero and
maximum frequencies of the output signal. Maximum output fre-