User guide

AirGate-Modbus
NOVUS AUTOMATION 17/22
LINK QUALITY INDICATOR
To evaluate if the equipment was installed in an appropriate manner, it is recommended to verify the quality of the
connection between each of the AirGate-Modbus and RHT-Air equipment units. This verification should be made by an
analysis of registers 36 and 39, while the network is operating. To make this analysis, it is possible to use the Diagnostic
tab of the DigiConfig that states the network typology and the quality of the link between each of the wireless connections
in an intuitive fashion.
For equipment operating in ideal conditions, where there are no obstacles and no type of electromagnetic interference,
the LQI will behave similarly to the contents of the graph shown in Fig. 17, where a comparison between different levels
of power for the Distance versus LQI ratio is made.
Fig. 13 – Ratio between Distance and LQI for several power levels
Table 4 lists the values obtained in the LQI reading with an evaluation of the signal quality. This same information can be
seen in a more intuitive fashion on the Diagnostic tab of the DigiConfig Software.
REGISTER
VALUE
QUALITY ICON
0
Device
connected via
USB
-15 to -60 Great
-60 to -70 Very Good
-70 to -80 Good
-80 to -90 Average
-90 to -100 Poor
Table 4 – Relation between LQI and Signal Quality
NOTE: The model described graphically considers only the means of propagation. The LQI may vary due to various
factors, such as peripheral obstacles such as trees, buildings, hills that interfere in the midst of the propagation, as
explained by the Fresnel Zone phenomenon.