Cameron NUFLO MC-III EXP, Руководство пользователя

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Section 4 MC-III™ EXP Flow Analyzer
To change the slave address, select a number using the “plus” and “minus” buttons on the screen, or using the
page-up and page-down keys on your computer keyboard. If Modbus
®
communication is not used, leave the
slave address at the factory setting (1).
Baud Rate
The baud rate is the number of bits per second that are on the serial port. Baud rates supported by the MC-III
EXP range from 300 to 115.2K. This setting must match the setting of the master device polling the MC-III
EXP or the serial port. This only applies to the Modbus
®
communications; if Modbus
®
is not used, set the baud
rate to 9600.
To change the baud rate, slide the selector bar to the appropriate setting. The default setting is 9600 baud.
Note that the 9600 baud rate is available in both the low-power and high-power modes. When the instrument
is powered by batteries alone, the low-power mode is recommended.
Auto-Negotiate Option
When connected devices are capable of switching baud rates automatically or when devices are directly
connected to an MC-III EXP, a user may configure the MC-III interface to automatically negotiate the fastest
baud rate during device connection. This “negotiated” baud rate does not replace the configured baud rate,
but rather provides a temporary boost of baud rate while the computer is connected to the device for faster
downloads. After the software disconnects, the device reverts to the configured baud rate.
By default, this function is disabled. To enable automatic baud rate negotiation on device connect, choose
Options/Program Options from the menu bar, select Communications from the dropdown options list, check
the “Attempt auto-negotiation...” checkbox, and click “OK” (Figure 4.19). To initiate an immediate search
for the fastest baud rate without exiting tto the Welcome screen, check the “Enable auto-negotiated baud
rate” checkbox, click the “Test Now” button to the right of the checkbox, and click “Yes” at the prompt in the
Confirm dialog box. See also Auto-Negotiate Option, page
B-4
.
Figure 4.19—Communications Options screen