Baker Hughes DigitalFlow XGF868i, Руководство по программированию

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C.6.3 Entering communications data
The XGF868i flowmeter is equipped with an RS232 serial
interface. The serial port is used to transmit stored data and
displayed readings to a personal computer by connecting
the meter’s serial interface to the serial port of the PC. In
addition, the XGF868i can receive and execute remote
commands, using PanaView software, via this link.
Use the comm port submenu to set the communications
port and MODBUS parameters. While following the
programming instructions, refer to Figure 57 on page 82
of Appendix D, PanaView menu maps .
C.6.3a Setting up the serial port
1. To enter this submenu from the global menu, highlight
and double-click on the comm port option in the
center pane.
2. Enter a meter address number between 1 and 254
and click [next item]. The default number is 1.
A meter address is only necessary for communication
with the Panametrics PanaView software. See the
PanaView user’s manual for more information.
IMPORTANT
If the meter address or baud rate is changed,
communication with PanaView must be re-established
with the new address number.
3. Double-click on the desired baud rate (from 300
to 19200).
If you have the MODBUS option, proceed to step 4 below.
If you have the standard RS232 serial interface, the meter
exits the comm port submenu and returns to the global
program prompt.
NOTE: The XGF868i MODBUS communication settings
chosen in the next four steps must match those of the
MODBUS control system.
4. Double-click on the desired MODBUS baud rate
(from 2400 to 9600).
5. Double-click on the desired MODBUS parity
(none, odd or even).
6. Double-click on the desired MODBUS stop bits (1 or 2).
7. Enter the desired MODBUS address .
The meter exits the comm port submenu and returns
to the global window. Click [exit page] once to return to
the site edit menu, and [close] to exit the site edit menu .
IMPORTANT
You must reboot the XGF868i to load the new settings.
Refer to the section Requesting parameters using
MODBUS on page 71 to retrieve data from the XGF868i
using MODBUS.
C.6.3b Requesting parameters using MODBUS
To request specific parameters from the XGF868i via
the MODBUS, the control system must access the
appropriate register number, as shown in Table 27 below.
Only registers 1–84 are available with the XGF868i for
MODBUS communications. Registers 508–512 are used by
the XGF868i to store the MODBUS parameters.
Table 27: MODBUS registers
MODBUS
reg #
DPR hex
addr
Description Scaling (decimal places) Size in bytes
MODBUS
reg #
1 0 1”clear ch1 totalizers” -- 2 (16 bit signed) 1
2 2 1“clear ch2 totalizers” -- 2 (16 bit signed) 2
3 4 Ch1 velocity 2 4 (2 16-bit int) 3
5 8 Ch1 act volumetric #Q DIGITS 4 (IEEE 32 bit) 5
7 C Ch1 std volumetric #Q DIGITS 4 (IEEE 32 bit) 7
9 10 Ch1 fwd totals #T DIGITS 4 (2 16 bit int) 9
71