ABB AWIN GW120, Руководство пользователя

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RECOMMENDATIO NS FO R ESTABLIS HING A RO BUST
WIRELESS HART NET WO RK WIR ELESS HART S YS TEM PLANNING
24 4JNO0 0030 8 A
4.5 Recommendations for Establishing a Robust
WirelessHART Network
To establish a robust WirelessHART network, follow these guidelines:
– All WirelessHART devices shall be operated as mesh nodes.
– If possible, install gateway or it’s antenna in the center of the target coverage area.
– Antenna should be mounted with free clearance around it (recommendation - 30cm) and
above the ground (1.5m or above). Antenna shall be installed vertically.
– There should be at least 5 devices or 10% of the total, whichever is larger, in the one-hop
ring.
– Every device should have at least 3 good neighbors. A good neighbor is a neighbor that
has RSSI >-75dBm or has >50% path stability. If not possible, add repeaters.
– Line of sight installation shall be kept to within 200m.
4.6 Maintaining System Performance
Over time, any communications system requires a degree of preventative maintenance to en-
sure peak operating efficiency. Periodic checks of master and remote sites should be made
to identify and correct potential problems before they become threats to system operation.
The following areas should be given special attention:
4.6.1 Antennas and coaxial cable
Visually inspect the antenna and coaxial cable for physical damage, and make sure that the
coaxial connections are tight and properly sealed against the weather. When using direc-
tional antennas, be sure that the antenna heading has not shifted since installation.
4.6.2 Cable connections
All power, data, and ground connections should be secure and free of corrosion.
4.6.3 Power supply
The input voltage to the gateway should be measured to verify that it is within the operating
specifications for the radio. Batteries, if used, should be checked for charge level and signs
of leakage or corrosion.