WI-GTWY-9-xxx Wireless Gateway V1.18
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Chapter 3
INSTALLATION
3.1
General
The WI-GTWY-9-xxx module is housed in a rugged aluminum case, suitable for DIN-rail
mounting. Terminals will accept wires up to 12 gauge (2.5 sqmm) in size.
All connections to the module must be low voltage (SELV). Normal 110-240V mains supply
should not be connected to any terminal of the WI-GTWY-9-xxx module.
Refer to Section
3.3
Power Supply
.
Before installing a new system, it is preferable to bench test the complete system. Configuration
problems are easier to recognize when the system units are adjacent. Following installation, the
most common problem is poor communications caused by incorrectly installed aerials, or radio
interference on the same channel, or the radio path being inadequate. If the radio path is a
problem (i.e. path too long, or obstructions in the way), then higher performance aerials or a
higher mounting point for the aerial may rectify the problem. Alternately, use an intermediate
WI-I/O 9-x Module as a repeater.
The foldout sheet WI-GTWY-9-xxx
Installation Guide
provides an installation drawing
appropriate to most applications. Further information is detailed below.
Each WI-GTWY-9-xxx module should be effectively earthed/grounded via the "GND" terminal
on the WI-I/O 9-x module - this is to ensure that the surge protection circuits inside the module
are effective.
3.2
Antenna Installation
The WI-GTWY-9-xxx and WI-I/O 9-x modules will operate reliably over large distances. The
distance which may be reliably achieved will vary with each application - depending on the type
and location of antennas, the degree of radio interference, and obstructions (such as hills or trees)
to the radio path. Typical reliable distances are :
USA/Canada 15 miles
6dB net gain antenna configuration permitted (4W ERP)
Australia/NZ 12 km
unity gain antenna configuration (1W ERP)
Longer distances can be achieved if one antenna is mounted on top of a hill.
To achieve the maximum transmission distance, the antennas should be raised above
intermediate obstructions so the radio path is true “line of sight”. Because of the curvature of the
earth, the antennas will need to be elevated at least 15 feet (5 metres) above ground for paths
greater than 3 miles (5 km). The modules will operate reliably with some obstruction of the
radio path, although the reliable distance will be reduced. Obstructions that are close to either
antenna will have more of a blocking effect than obstructions in the middle of the radio path. For
example, a group of trees around the antenna is a larger obstruction than a group of trees further
away from the antenna. The WI-GTWY-9-xxx modules provide a test feature that displays the
radio signal strength.