Adcon A850, Руководство пользователя

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CHAPTER 1
Introduction
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The forwarding of the data from the A850 to the data assessment
PC is achieved either through
• Ethernet or
• Telephone Modem.
For data communication from and to an A850, private (LAN, VPN)
or public means for data communications (e.g. the Internet) can be
used.
The Gateway is based on a powerful 32 bit ARM processor running
the Linux operating system. It has 256 MB Compact Flash acting as
a hard disk and 64 MB RAM.
The Compact Flash data storage device of the A850 with its capa-
city of 256 MB allows to buffer data sampled from 1000 stations for
14 days. The built-in rechargeable battery maintains the function of
the A850 also in case of temporary outages of the primary power
source for up to approximately 24 hours (the achievable time of
operation without mains power depends on the number of RTUs
the Gateway has to poll), preventing any data loss. The central unit
is prepared for future software updates and can be upgraded on
location. The communication with the Wireless Modem A440
mounted e.g. on a roof will be ensured by a serial RS-485 connec-
tion. This connection uses a cable which is by default 30 m long
and easy to lay. Upon request, special low-attenuation cables of up
to 90 m can be provided by Adcon.
The A440 Wireless Modem is a low-power, narrow-band data
transceiver operating in the 70 cm band. It implements Adcon's
low-speed radio protocol and is therefore compatible with all
Adcon RTUs. In addition, the A440 modem supports a high-speed
wireless protocol that will be used by future Adcon devices. The
A440 has an 8 bit Flash-based microcontroller and can also be
updated in the field. The A440 is delivered in an IP-65/67 enclo-
sure.