Campbell NL200, Инструкция по эксплуатации

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NL200/201 Network Link Interface
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7.3.4 Connect
You are now ready to connect to your datalogger using the
LoggerNet Connect
screen.
7.3.5 Serial Sensors
The NL200/201 configured as an RS-232 serial server as described above can
be used to communicate with a serial sensor. However,
LoggerNet
is not
capable of communicating with the serial sensor. You must have some other
method of communicating with the sensor.
7.4 TCP Serial Client
When the RS-232 port is configured as TCP Serial Client , the NL200/201 will
initiate and maintain a TCP socket connection to the IP address and port
number specified by the
Serial Client Address and Serial Client Port
settings. Data received on the RS-232 port will be forwarded to this TCP
connection, and data received on the TCP connection will be forwarded to the
RS-232 port. This mode can be particularly useful when an RF base or serial
sensor is behind a firewall and needs to be the party responsible for initiating
the TCP socket connection to the data collection server.
The NL200/201 will attempt to open a connection with the remote server, and,
if the connection fails to open, the device will continue to retry at an interval of
60 seconds. If data arrives on the RS-232 port when no TCP connection exists,
the device will buffer the data (up to 1500 bytes) and immediately attempt to
open a connection to deliver the data. If the remote server closes the
connection due to error, the NL200/201 will make a best effort to save any data
that was in process and re-queue it to be sent on the next successfully-opened
TCP connection.
7.5 Modbus TCP/IP to RTU Gateway
The NL200/201 can serve as a Modbus TCP/IP to RTU Gateway. It will listen
for incoming Modbus TCP/IP connections from a Modbus TCP/IP master
client. The port number of the listening connection is specified in the
RS-232
Service Port Number setting and is typically set to a value of 502. The
NL200/201 will convert incoming Modbus TCP/IP frames to Modbus RTU
and forward them to the RS-232 port. The NL200/201 will wait for a response
from the Modbus RTU device and forward that response back to the remote
Modbus TCP/IP master client over the established TCP connection. The
Modbus RTU device is generally a datalogger, such as a CR200(X), connected
to the RS-232 port or a datalogger located remotely over a transparent radio
(for example, RF450) connection, but can be any Modbus RTU device. When
the NL200/201 is connected directly to a CR800 series, CR1000, or CR3000
being polled by a Modbus TCP/IP master client, the NL200/201 is most
commonly configured with Bridge Mode enabled instead of as a Modbus
TCP/IP to RTU Gateway.
7.6 TLS
The NL200/201 supports transport layer security (TLS) for proxy functions
including HTTPS. TLS versions 1.0 and 1.1. are supported. The TLS
implementation supports symmetric algorithms AES-256, AES-128, and RC4
and RSA keys up to 4096 bits. For any TLS connection, the unit will