Davis Instruments GroWeatherLink, Руководство пользователя

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H
A R D W A R E
I
N S T A L L A T I O N
There are three basic types of installations: direct connection, phone modem con-
nection, and radio multi-point connection.
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Direct connection
Involves connecting the GroWeatherLink/ET Data Logger (simply referred to
as “WeatherLink”) directly to your computer. Direct connections include
installations that use Davis’ Short-Range Modem Pair (#7875) and/or a base
and station (i.e., single-point) radio.
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Phone modem connection
Refers specifically to any installation where the WeatherLink is connected to a
telephone modem and a second modem is connected to your computer.
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Radio multi-point connection
Refers to installations where more than one station transmits WeatherLink
data to your computer via radio modem.
Note:
If you have not yet purchased a remote communications device—such as a telephone or
radio modem—and you would like to know more about the various options, contact our
tech support team (at 510-732-7814) and ask for the “WeatherLink Radio Communica-
tions” application note.
H
A R D W A R E
R
E Q U I R E M E N T S
The required hardware differs depending on whether you are attempting to make
a direct connection, phone modem connection, or radio multi-point connection.
Direct Connection Hardware Requirements
In addition to the provided hardware, check that you have the following items.
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GroWeatherLink/ET Data Logger
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Computer running Windows™ 3.1, NT, or 95 with at least 5 MB of free disk space, 4MB
of RAM, and one free serial port
The amount of space necessary for the data files depends on the archive inter-
val. Database files containing data stored at a 30-minute archive interval
require approximately 64K of disk space per month of data. The file size
changes in a linear fashion depending on the archive interval. For example,
data stored at a 1 minute interval requires approximately 1.92 MB/month
while the data stored at a 2 hour interval requires approximately 16K/month.
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Short-Range Modem Pair (SRM)—optional
For transmitting data over twisted-pair cable at a distance of up to seven miles
(11 km). SRM (#7875) and twisted pair cable (#7884) available from Davis.
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Radio—optional
You may use a third-party radio to transmit data from the WeatherLink to the
PC or SRM. Davis offers an installation kit for two such radios (see “Radio
Multi-Point Connection” on page 9 for more information). May also require
Alarm Output Module to conserve power.