Banner SureCross DX80 Wireless Networks - Manual (Page 18)

7. Change the Gateway's right rotary dial to conduct a Site Survey with another Node and repeat steps 2 through 6.
8. To end the Site Survey, double-click button 2.
9. Change the Gateway's right rotary dial back to 0.
The LCD displays the device readings for the Gateway.
10. Double-click button 2 to move back to the top level menu.
11. Single-click button 1 to return to RUN mode.
12. Install the rotary dial access cover, referring to the Installation section of the manual to create an IP67 seal.
3.7.2 Interpreting the Site Survey Results
Site Survey results are listed as a percentage of data packets received and indicate the signal strength of the received
signal.
Result Description
Green Packets received at a strong signal strength. A strong signal strength is
greater than −90 dBm at the receiver.
Yellow Packets received at a good signal strength. A good signal is between
−90 and −100 dBm at the receiver.
Red Packets received at a weak signal strength. A weak signal is less than
−100 dBm at the receiver.
Missed Packets not received on the first transmission and requiring a retry.
Judging if the reliability of a network’s signal meets the needs of the application is not just a matter of green, yellow, and
red packets received. In normal operating mode, when data packets are not received, the transmitter re-sends the packet
until all data is received.
For slow monitoring applications such as a tank farm, where data is required in terms of seconds or minutes, receiving
most of the data in the ‘red’ range, indicating a weak but reliable signal, transmits enough data for accurate monitoring.
Nodes positioned near the outside range of the radio signal may have 90% of the data packets received in the red zone,
again indicating a weak, but reliable signal.
We recommend keeping the missed packets average to less than 40%. When the network misses more than 40% of the
data packets, the signal is usually too unreliable or obstacles may be interfering with the signal. When Site Survey reports
the missed packets are 40% or higher, improve the radio system performance by:
• Mounting the network’s antennas higher,
• Using higher gain antennas, or
• Adding data radios to the network.
Mounting the devices’ antennas higher allows the radio signal to clear obstacles in the area and improves the line of sight
between SureCross ® devices. Higher gain antennas focus the energy of the radio signal in a specific direction and extend
the signal’s range. Using data radios is another option to consider when trying to extend the range of a radio network. For
more information on data radios, please refer to Banner’s white paper on range extension on
www.bannerengineering.com/surecross .
SureCross Wireless I/O Networks
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