RSSI Value Meaning

I am using the MQTT Micro Gateway paired with the preventative maintenance sensor package.

The sensor package is publishing a RSSI value to Ubidots of around 20 RSSI.

I don’t know if a negative sign is being truncated but my question is 100 RSSI value full strength or if 0 RSSI value full signal strength.

Below is a snapshow of my sensor RSSI value over a bit of time.


The RSSI value we publish is 0-100 with 100 being perfect signal.