Campbell CRVW3, Инструкция по эксплуатации

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CRVW3 3-Channel Vibrating-Wire Datalogger
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Sometimes an office building is within radio distance of some of the CRVW3
devices and some of the repeaters. In that case, LoggerNet can run in the office,
and steps are taken to mount an antenna for use by the base radio somewhere
on the exterior of the office building. The antenna cable is fed through to the
base radio, which is located inside the building near the
LoggerNet
computer
and connected via a serial cable.
Another option is to use a TCP/IP, Wi-Fi, Cell Modem, RS-485 or other kind
of communications link (different from the radio links) in the field location that
will connect between the base station radio and
LoggerNet
at a remote location.
In these scenarios, LoggerNet is located at the office or at a hosted site and uses
TCP/IP (or another data protocol) to make a remote connection to the base
radio station. The base station is located somewhere within range of the
CRVW3 devices and the repeaters. The base station in this instance contains its
main radio but also hosts another device. This can be an NL201 (or similar
serial-to-Ethernet bridge), an NL240 (or other serial-to-Wi-Fi bridge), an RV50
(or similar cell modem to TCP/IP gateway), or an MD485 for enabling RS-485
wired communications. The base radio and the bridging device are linked
together. When installed in this way, LoggerNet can control the base radio via
TCP/IP (or other data protocol) even though the two stations are located at a
significant distance from each other.
If multiple people need to interact with the same
LoggerNet
computer in your
office, you should strongly consider the use of LoggerNet Admin (installed on
the LoggerNet computer or server), and LoggerNet Remote (which is installed
on an individual’s workstation PC in the office and connects as a client to
LoggerNet Admin ). See Section 10.1.1 , LoggerNet Computer Station
(p. 58)
, or
www.campbellsci.com/LoggerNet for more information.
Once the location of the LoggerNet computer station is known, indicate it on
the map of your network plan, and begin making arrangements for the other
items necessary for it to connect with the base station.
10.2.5 Planning the Base Station
The location of the base radio station should be selected carefully. The base
station must have good radio connectivity with all repeater stations and with as
many CRVW3 end-node stations as possible. In addition, it must be able to
communicate with the LoggerNet computer station. The main purpose of the
base station is to be a bridge or gateway between your CRVW3 radio network
and the rest of the world (any other remote devices that need to communicate
with your CRVW3 devices). Please refer to the diagram in Section 10.1.2 , Base
Radio Station
(p. 59)
.
Usually a base station requires an omnidirectional antenna since it
communicates with multiple remote stations. In the less-common case where
the base station communicates with only one remote repeater (through which
all other stations route), a directional antenna (Yagi) can be used.
LoggerNet
is usually the main device outside the radio network that
communicates with the base station. Choose a location that allows the base
station to establish a link to the LoggerNet computer station. Sometimes the
LoggerNet computer and the base station are at the same location. In other
deployments, they are remotely located and communicate via a TCP/IP
telemetry device, or similar. For more information about making connections