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3 installation, 1 mounting considerations, 3installation – VEGA WHA-GW-WIRELESSHART GATEWAY User Manual

Page 18: Wha-gw, Installation, 2 antenna characteristics

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Installation

3

Installation

3.1

Mounting Considerations

3.1.1

Positioning the Gateway

Install the Gateway first, before installing other WirelessHART devices. This way you can

check for proper operation of new devices as they are installed. Nevertheless, consider the

location of future WirelessHART devices that will be routed through the Gateway to ensure

good connectivity.

Guidelines for Planning a WirelessHART Network

A line-of-sight between communication partners always is desirable. If a line-of-sight is
not possible, the obstacles should not be massive and the partners should be more to
the edge of an obstacle to allow the wave to "bend" around it (diffraction effect).

Consider moving objects that could affect the device's antenna range.

Install wireless devices at least 1 m above the ground or the floor.

Make sure that the device's antenna is aligned vertically for best results.

Make sure that a minimum of 2 other WirelessHART devices are well within the antenna
range of the device (see chapter 9). For more information on the antenna
characteristics please refer to the following section.

Do not position WirelessHART devices directly below or above each other. They would
be outside each other's antenna range.

Install WirelessHART devices at least 1 m away from each other.

Antennas must be at least 6 cm away from any wall or any metallic material running
parallel to it.

Position the device as far away as possible from metal surfaces or walls containing
metal. There should be as little metal close to the device as possible.

Do not position other 2.4 GHz devices like cordless phone bases or WLAN routers near
WirelessHART devices. Keep in mind other wireless networks using the same
frequency spectrum (WLAN, Bluetooth, etc.). Wireless technologies used in an
industrial environment must be able to coexist without disrupting each other. If multiple
networks operate in one facility, a frequency management should be applied as part of
administration.

If it is not possible to mount the device outdoors, connect a remote antenna to the antenna

terminal and mount the remote antenna outdoors. The antenna cable should not be longer

than 15 m.

3.1.2

Antenna Characteristics

The antenna is an omni-directional dipole antenna. If you point the antenna upwards, the

signal radiates horizontally with an angle of approx. 45 degrees above and below the

horizontal (donut shaped). Allmost no signal will be radiated directly above and below the

antenna. Consider this when planning a WirelessHART network. The height differences

between wireless devices in a network should not be too big.

This is only valid for an antenna placed outdoors with no metal surfaces near. The radiation

pattern changes significantly when metal surfaces are close to the antenna.