Understanding LQI values Zigbee2MQTT

Configuration Zigbee
1

I really don’t understand what Zigbee2MQTT is telling me…
Lets take any device from my installation as an example (This one happens to be a battery powered radiator valve) . The LQI on the main Z2m screen show the LQI as 98 but on the Z2M map screen the value shown on the green dotted connection line for this valve shows as 228. - which one is correct and why are they different ?
Also on the powered devices (which are repeating) I get an LQI of 90 on the device screen and then 93/81 on the map screen ? so again, which one is correct and why are there two numbers on some connections i.e 91/83 and then only a single figure on others.
Finally, why do some connections show as 0 or 0/0 ?
I’ve looked everywhere for an explanation with no luck so I’m hoping someone can enlighten me !

1 Like
2

All of these are my presumptions:

The LQI on the main screen is what the end device is reporting as it’s receive link quality (since that’s a reported attribute if you look at the “exposes” section for the device page) whereas the Z2M map is showing what the routing device has for LQI to that end device (since the map is generated by the routing tables provided by the routers).

For routing devices, the dual numbers are LQI for the device’s receive and LQI for the coordinators receive.

My guess on the disparities between the device page and the map are that the map is polling the device for it’s route table and getting the LQI at that point in time, where the device entry is showing the last reported value from the device’s last update (whenever that may have been).

I’ve never seen a goose-egged connection before. Maybe it’s showing that the device is connected, but the map was unable to get the current LQI values to show.

3

I have a lot of them on my network map, but that is not really important. If a router has 10 different routes (common on my map) and 1 or 2 show 0/0, they still have enough valid routes. It probably were once valid routes, but the device found better routes.

4

My understanding is;

  • device list shows the minimum of the path for each device (min(coordinator to router 1 to router 2 to end device))
  • map shows the strength of specific links such as router 2 to end device.
5

RSSI numbers above the mid-80s
LQI’s below 200

you’re dealing with signals that are mostly noise.