Vaisala LT31, Руководство пользователя

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Chapter 4 _______________________________________________________________ Installation
VAISALA ______________________________________________________________________ 135
OPEN Command
Users enter the command mode with the OPEN command.
Type the following:
open
If an ID is configured, use command:
open *
If no ID is configured, the LT31 sensor answers as follows:
0> LT31 line opened for operator commands
If no input is given within 10 minutes (default), LT31 closes the line
automatically and gives the following answer:
LT31 line closed
CLOSE Command
The line can be released to automatic data messages with the CLOSE
command.
If no ID is configured, LT31 answers as follows:
LT31 line closed
For details, see Chapter 5, Operation, on page 145.
Initial Settings
Vaisala Transmissometer LT31 is typically interfaced to a host computer
or a data logger in an automatic weather observation system. After the
physical connection has been made, the details of the communication can
be configured into the LT31 software. Suitable communication settings
depend on the implementation of the entire system.
By default the sensor transmits a new ASCII data message through the
data port in RS-232 mode every 10 seconds. The user can change the
interval and message type. The sensor can also be used in a polled mode,
in which a data message is only sent when the host computer requests
one with a special command. The default settings are listed in Table 9 on
page 136.